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 Author ID: arnold.vladimir-igorevich Published as: Arnol’d, V. I.; Arnold, V. I.; Arnold, Vladimir I.; Arnold, V.; Arnold, Vladimir; Arnol’d, V.; Arnol’d, Vladimir Igorevich; Arnold, Vladimir Igorevich; Arnol’d, Vladimir I.; Arnold, Vładimir I.; Arnold, W. I. Further Spellings: Арнольд Владимир Игоревич Homepage: http://www.pdmi.ras.ru/~arnsem/Arnold/ External Links: MacTutor · MGP · Wikidata · Math-Net.Ru · dblp · GND · IdRef · theses.fr Awards: Wolf Prize (2001)
 Documents Indexed: 405 Publications since 1957, including 75 Books 32 Contributions as Editor · 8 Further Contributions Biographic References: 32 Publications Co-Authors: 154 Co-Authors with 106 Joint Publications 4,424 Co-Co-Authors
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### Fields

 141 Global analysis, analysis on manifolds (58-XX) 116 Dynamical systems and ergodic theory (37-XX) 86 Manifolds and cell complexes (57-XX) 69 History and biography (01-XX) 54 General and overarching topics; collections (00-XX) 49 Differential geometry (53-XX) 48 Mechanics of particles and systems (70-XX) 46 Ordinary differential equations (34-XX) 40 Number theory (11-XX) 34 Algebraic geometry (14-XX) 19 Fluid mechanics (76-XX) 18 Several complex variables and analytic spaces (32-XX) 17 Group theory and generalizations (20-XX) 15 Combinatorics (05-XX) 15 Partial differential equations (35-XX) 8 Real functions (26-XX) 8 Convex and discrete geometry (52-XX) 8 Probability theory and stochastic processes (60-XX) 7 Commutative algebra (13-XX) 6 General topology (54-XX) 6 Algebraic topology (55-XX) 6 Optics, electromagnetic theory (78-XX) 5 Calculus of variations and optimal control; optimization (49-XX) 4 Geometry (51-XX) 4 Quantum theory (81-XX) 4 Statistical mechanics, structure of matter (82-XX) 4 Astronomy and astrophysics (85-XX) 3 Linear and multilinear algebra; matrix theory (15-XX) 3 Operator theory (47-XX) 3 Mechanics of deformable solids (74-XX) 3 Systems theory; control (93-XX) 3 Mathematics education (97-XX) 2 Associative rings and algebras (16-XX) 2 Nonassociative rings and algebras (17-XX) 2 Topological groups, Lie groups (22-XX) 2 Functions of a complex variable (30-XX) 2 Special functions (33-XX) 2 Sequences, series, summability (40-XX) 2 Abstract harmonic analysis (43-XX) 2 Functional analysis (46-XX) 2 Relativity and gravitational theory (83-XX) 1 Field theory and polynomials (12-XX) 1 Category theory; homological algebra (18-XX) 1 Measure and integration (28-XX) 1 Harmonic analysis on Euclidean spaces (42-XX) 1 Statistics (62-XX) 1 Numerical analysis (65-XX) 1 Computer science (68-XX) 1 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 1 Biology and other natural sciences (92-XX)

### Citations contained in zbMATH Open

312 Publications have been cited 7,337 times in 6,240 Documents Cited by Year
Mathematical methods of classical mechanics. Translated by K. Vogtman and A. Weinstein. Zbl 0386.70001
Arnold, V. I.
1978
Sur la géométrie différentielle des groupes de Lie de dimension infinite et ses applications à l’hydrodynamique des fluides parfaits. Zbl 0148.45301
Arnol’d, V. I.
1966
Topological methods in hydrodynamics. Zbl 0902.76001
Arnold, V. I.; Khesin, B. A.
1998
Geometrical methods in the theory of ordinary differential equations. Transl. from the Russian by Joseph Szuecs, ed. by Mark Levi. Zbl 0507.34003
Arnold, V. I.
1983
Ergodic problems of classical mechanics. Zbl 0167.22901
Arnol’d, V. I.; Avez, A.
1968
Mathematical aspects of classical and celestial mechanics. Transl. from the Russian by A. Iacob. 2nd printing of the 2nd ed. 1993. Zbl 0885.70001
Arnold, V. I.; Kozlov, V. V.; Neishtadt, A. I.
1997
Small denominators and problems of stability of motion in classical and celestial mechanics. Zbl 0135.42701
Arnol’d, V. I.
1963
Mathematical aspects of classical and celestial mechanics. Transl. from the Russian by E. Khukhro. 3rd revised ed. Zbl 1105.70002
2006
Singularities of differentiable maps, Volume 1. Classification of critical points, caustics and wave fronts. Transl. from the Russian by Ian Porteous, edited by V. I. Arnol’d. Reprint of the 1985 hardback edition. Zbl 1290.58001
Arnold, V. I.; Gusein-Zade, S. M.; Varchenko, A. N.
2012
Proof of a theorem of A. N. Kolmogorov on the invariance of quasi-periodic motions under small perturbations of the Hamiltonian. Zbl 0129.16606
Arnol’d, V. I.
1963
Singularities of differentiable maps, Volume 2. Monodromy and asymptotics of integrals. Transl. from the Russian by Hugh Porteous and revised by the authors and James Montaldi. Reprint of the 1988 hardback edition. Zbl 1297.32001
Arnold, V. I.; Gusein-Zade, S. M.; Varchenko, A. N.
2012
Instability of dynamical systems with several degrees of freedom. Zbl 0135.42602
Arnol’d, V. I.
1964
Mathematical methods of classical mechanics. Textbook. 3rd ed., rev. and compl. (Математические методы классической механики. Учебное пособие.) Zbl 0692.70003
Arnol’d, V. I.
1989
Small denominators. I: Mappings of the circumference onto itself. Zbl 0152.41905
Arnol’d, V. I.
1965
On matrices depending on parameters. Zbl 0259.15011
Arnol’d, V. I.
1972
Ordinary differential equations. Translated and edited by Richard A. Silverman. Zbl 0296.34001
Arnold, V. I.
1973
Wave front evolution and equivariant Morse lemma. Zbl 0343.58003
Arnol’d, V. I.
1976
Ergodic problems of classical mechanics. Transl. from the French. Reprint. Zbl 0715.70004
Arnold, V. I.; Avez, A.
1989
Loss of stability of self-oscillations close to resonance and versal deformations of equivariant vector fields. Zbl 0411.58013
Arnol’d, V. I.
1977
Singularities of differentiable maps. Volume I: The classification of critical points, caustics and wave fronts. Transl. from the Russian by Ian Porteous, ed. by V. I. Arnol’d. Zbl 0554.58001
Arnol’d, V. I.; Gusejn-Zade, S. M.; Varchenko, A. N.
1985
Characteristic class entering in quantization conditions. Zbl 0175.20303
Arnol’d, V. I.
1967
Problèmes ergodiques de la mécanique classique. Zbl 0149.21704
Arnol’d, V. I.; Avez, A.
1967
The cohomology ring of the colored braid group. Zbl 0277.55002
Arnol’d, V. I.
1969
Topological methods in hydrodynamics. Zbl 0743.76019
Arnold, V. I.; Khesin, B. A.
1992
Normal forms for functions near degenerate critical points, the Weyl groups of A$$_k$$, D$$_k$$, E$$_k$$ and lagrangian singularities. Zbl 0278.57011
Arnol’d, V. I.
1973
Sur la topologie des ecoulements stationnaires des fluides parfaits. Zbl 0145.22203
Arnol’d, V. I.
1965
Index of a singular point of a vector field, the Petrovskii-Oleinik inequality, and mixed Hodge structures. Zbl 0407.57025
Arnol’d, V. I.
1978
Local normal forms of functions. Zbl 0336.57022
Arnold, V. I.
1976
Théorie des perturbations et méthodes asymptotiques. Suivi de deux notes complementaires de V. I. Arnol’d et V. C. Bouslaev. Traduit par J. Lascoux et R. Seneor. Zbl 0247.47010
Maslov, V. P.
1972
Mathematical methods of classical mechanics. (Математические методы классической механики.) Zbl 0647.70001
Arnol’d, V. I.
1974
Chapitres supplementaires de la théorie des équations différentielles ordinaires. Traduit du russe par Djilali Enbarek. Zbl 0455.34001
Arnold, V.
1980
Singularities of differentiable maps. Volume II: Monodromy and asymptotics of integrals. Transl. from the Russian by Hugh Porteous. Zbl 0659.58002
Arnol’d, V. I.; Gusejn-Zade, S. M.; Varchenko, A. N.
1988
Lectures on bifurcations in versal families. Zbl 0264.58005
Arnol’d, V. I.
1973
Conditions for nonlinear stability of stationary plane curvilinear flows of an ideal fluid. Zbl 0141.43901
Arnol’d, V. I.
1965
On an apriori estimate in the theory of hydrodynamical stability. Zbl 0191.56303
Arnol’d, V. I.
1969
Ordinary differential equations. Zbl 0659.58012
Arnol’d, V. I.; Il’yashenko, Yu. S.
1988
Supplementary chapters to the theory of ordinary differential equations. (Dopolnitel’nye glavy teorii obyknovennykh differentsial’nykh uravnenij.) Zbl 0956.34503
Arnol’d, V. I.
1978
Singularities of caustics and wave fronts. Transl. from the Russian. Zbl 0734.53001
Arnol’d, V. I.
1990
Geometrical methods in the theory of ordinary differntial equations. Transl. from the Russian by Joseph Szücs. Engl. Transl. ed. by Mark Levi. 2nd ed. Zbl 0648.34002
Arnol’d, V. I.
1988
Remarks on singularities of finite codimension in complex dynamical systems. Zbl 0249.34035
Arnol’d, V. I.
1969
The asymptotic Hopf invariant and its applications. Zbl 0623.57016
Arnol’d, V. I.
1986
Arnold’s problems. Translated and revised edition of the 2000 Russian original. Zbl 1051.00002
2004
Critical points of smooth functions and their normal forms. Zbl 0343.58001
Arnol’d, V. I.
1975
Mathematical aspects of classical and celestial mechanics. Zbl 0674.70003
Arnol’d, V. I.; Kozlov, V. V.; Nejshtadt, A. I.
1987
First steps in symplectic topology. Zbl 0649.58010
Arnol’d, V. I.
1986
Plane curves, their invariants, perestroikas and classifications. Zbl 0864.57027
Arnold, V. I.
1994
Mathematical aspects of classical and celestial mechanics. Zbl 0612.70002
Arnol’d, V. I.; Kozlov, V. V.; Nejshtadt, A. I.
1985
Les méthodes mathématiques de la mécanique classique. Traduit du russe par Djilali Embarek. Zbl 0385.70001
Arnol’d, V.
1976
Some algebro-geometrical aspects of the Newton attraction theory. Zbl 0569.58018
Arnol’d, V. I.
1983
Modes and quasimodes. Zbl 0251.70012
Arnol’d, V. I.
1972
Normal forms of functions in neighbourhoods of degenerate critical points. Zbl 0304.57018
Arnol’d, V. I.
1974
Sur une propriété topologique des applications golbalement canoniques de la mécanique classique. Zbl 0134.42305
Arnol’d, V. I.
1965
Remarks on the perturbation theory for problems of Mathieu type. Zbl 0541.34035
Arnol’d, V. I.
1983
Dynamical systems I. Ordinary differential equations and smooth dynamical systems. Transl. from the Russian. Zbl 0658.00008
1988
The Sturm theorems and symplectic geometry. Zbl 0606.58017
Arnol’d, V. I.
1985
Symplectic geometry. Zbl 0780.58016
Arnol’d, V. I.; Givental’, A. B.
1985
Some unsolved problems in the theory of differential equations and mathematical physics. Zbl 0703.35002
Arnol’d, V. I.; Vishik, M. I.; Il’yashenko, Yu. S.; Kalashnikov, A. S.; Kondrat’ev, V. A.; Kruzhkov, S. N.; Landis, E. M.; Millionshchikov, V. M.; Oleĭnik, O. A.; Filippov, A. F.; Shubin, M. A.
1989
The geometry of spherical curves and the algebra of quaternions. Zbl 0848.58005
Arnol’d, V. I.
1995
Indices of singular points of 1-forms on a manifold with boundary, convolution of invariants of reflection groups, and singular projections of smooth surfaces. Zbl 0431.58010
Arnol’d, V. I.
1979
Topological classification of Morse functions and generalisations of Hilbert’s 16-th problem. Zbl 1149.57044
2007
On functions of three variables. Zbl 0090.27101
Arnol’d, V. I.
1957
Statistics of integral convex polygons. Zbl 0447.52011
Arnol’d, V. I.
1980
Higher dimensional continued fractions. Zbl 1044.11596
Arnold, V. I.
1998
Kolmogorov’s hydrodynamic attractors. Zbl 0726.76045
Arnol’d, V. I.
1991
Dynamics of complexity of intersections. Zbl 0782.54020
Arnold, V. I.
1990
Catastrophe theory. Transl. from the Russian by R. K. Thomas. Zbl 0517.58003
Arnold, V. I.
1984
Remarks on eigenvalues and eigenvectors of Hermitian matrices, Berry phase, adiabatic connections and quantum Hall effect. Zbl 0841.58008
Arnold, V. I.
1995
Critical points of functions on a manifold with boundary, the simple Lie groups $$B_4$$, $$C_k$$, and $$F_4$$ and singularities of evolutes. Zbl 0415.58004
Arnol’d, V. I.
1978
Topological and ergodic properties of closed 1-forms with incommensurable periods. Zbl 0732.58001
Arnol’d, V. I.
1991
Topological classification of trigonometric polynomials and combinatorics of graphs with an equal number of vertices and edges. Zbl 0898.32019
Arnold, V. I.
1996
Singularity theory I. Transl. from the Russian by A. Iacob. 2nd printing of the 1st ed. 1993. Zbl 0901.58001
Arnold, V. I.; Goryunov, V. V.; Lyashko, O. V.; Vasil’ev, V. A.
1998
A-graded algebras and continued fractions. Zbl 0692.16012
Arnol’d, V. I.
1989
Equations différentielles ordinaires. Champs de vecteurs. Groupes à un paramètre. Difféomorphismes. Flots. Systemes linéaires. Stabilites des positions d’équilibre. Théorie des oscillations. Equations différentielles sur les variétés. Traduit du russe par Djilali Embarek. Zbl 0296.34002
Arnold, V.
1974
The stability of the equilibrium position of a Hamiltonian system of ordinary differential equations in the general elliptic case. Zbl 0135.42601
Arnol’d, V. I.
1961
Singularities of smooth mappings. Zbl 0167.21702
Arnol’d, V. I.
1968
Singularity theory. Selected papers. Zbl 0457.58002
Arnold, V. I.
1981
Sur un principe variationnel pour les ecoulements stationnaires des liquides parfaits et ses applications aux problèmes de stabilité non linéaires. Zbl 0161.22903
Arnol’d, V. I.
1966
Mathematical problems in classical physics. Zbl 0806.53078
Arnold, V. I.
1994
A branched covering of $$CP^ 2\to S^ 4$$, hyperbolicity and projectivity topology. Zbl 0721.57003
Arnol’d, V. I.
1988
Remarks on the stationary phase method and Coxeter numbers. Zbl 0291.40005
Arnol’d, V. I.
1973
The calculus of snakes and the combinatorics of Bernoulli, Euler, and Springer numbers of Coxeter groups. Zbl 0791.05001
Arnol’d, V. I.
1992
Cardiac arrythmias and circle mappings. Zbl 0900.92094
Arnold, V. I.
1991
Newton’s Principia read 300 years later. Zbl 0693.01005
Arnol’d, V. I.; Vasil’ev, V. A.
1989
Bernoulli-Euler updown numbers associated with function singularities, their combinatorics and arithmetics. Zbl 0755.58015
Arnol’d, V. I.
1991
Ordinary differential equations. Textbook. (Obyknovennye differentsial’nye uravneniya. Uchebnoe posobie). 3rd ed., rev. and compl. Zbl 0577.34001
Arnol’d, V. I.
1984
Some remarks on flows of line elements and frames. Zbl 0124.14601
Arnol’d, V. I.
1961
Weak asymptotics for the numbers of solutions of Diophantine problems. Zbl 1042.11064
Arnol’d, V. I.
1999
Some remarks on symplectic monodromy of Milnor fibrations. Zbl 0970.53043
Arnold, V. I.
1995
Lectures on partial differential equations. (Vorlesungen über partielle Differentialgleichungen. Übersetzt aus dem Russischen von Tobias Damm.) Zbl 1076.35001
Arnold, V. I.
2004
Singularities of systems of rays. Zbl 0531.58009
Arnol’d, V. I.
1983
Catastrophe theory. Translated from the Russian by G. S. Wassermann. Based on the translation by R. K. Thomas. 3. rev. and exp. ed. Zbl 0746.58001
Arnol’d, V. I.
1992
Variational principle for three-dimensional steady-state flows of an ideal fluid. Zbl 0163.19807
Arnol’d, V. I.
1965
Bifurcation theory. Zbl 0797.58003
Arnol’d, V. I.; Afrajmovich, V. S.; Il’yashenko, Yu. S.; Shil’nikov, L. P.
1986
Catastrophe theory. Zbl 0797.58002
Arnol’d, V. I.
1986
Dynamical systems. I: Ordinary differential equations. Zbl 0602.58020
Arnol’d, V. I.; Il’yashenko, Yu. S.
1985
Contact geometry: The geometrical method of Gibb’s thermodynamics. Zbl 0737.53029
Arnold, V. I.
1990
Ordinary differential equations and smooth dynamical systems. Transl. from the Russian by E. R. Dawson and D. O’Shea. 3rd printing of the 1st ed. 1988. Zbl 0858.34001
Anosov, D. V.; Aranson, S. Kh.; Arnold, V. I.; Bronshtein, I. U.; Grines, V. Z.; Il’yashenko, Yu. S.
1997
Optimization in mean and phase transitions in controlled dynamical systems. Zbl 1057.49003
Arnol’d, V. I.
2002
Fermat dynamics, matrix arithmetics, finite circles, and finite Lobachevsky planes. Zbl 1125.11066
Arnold, V. I.
2004
Topological invariants of plane curves and caustics. Zbl 0858.57001
1994
Topological methods in hydrodynamics. 2nd edition. Zbl 1475.76003
Arnold, Vladimir I.; Khesin, Boris A.
2021
Experimental mathematics. Zbl 1323.00003
Arnold, V. I.
2015
Lectures and problems: a gift to young mathematicians. Translated by Dmitry Fuchs and Mark Saul. Zbl 1331.00009
Arnold, V. I.
2015
Vladimir I. Arnold – Collected works. Vol. II. Hydrodynamics, bifurcation theory, and algebraic geometry 1965–1972. Edited by Alexander B. Givental, Boris A. Khesin, Alexander N. Varchenko, Victor A. Vassiliev and Oleg Ya. Viro. Zbl 1354.01038
2014
Mathematical understanding of nature. Essays on amazing physical phenomena and their understanding by mathematicians. Translated from the Russian by Alexei Sossinsky and Olga Sipacheva. Zbl 1302.00049
Arnold, V. I.
2014
Real algebraic geometry. Translated from the Russian by Gerald G. Gould and David Kramer. Zbl 1268.14001
2013
Singularities of differentiable maps, Volume 1. Classification of critical points, caustics and wave fronts. Transl. from the Russian by Ian Porteous, edited by V. I. Arnol’d. Reprint of the 1985 hardback edition. Zbl 1290.58001
Arnold, V. I.; Gusein-Zade, S. M.; Varchenko, A. N.
2012
Singularities of differentiable maps, Volume 2. Monodromy and asymptotics of integrals. Transl. from the Russian by Hugh Porteous and revised by the authors and James Montaldi. Reprint of the 1988 hardback edition. Zbl 1297.32001
Arnold, V. I.; Gusein-Zade, S. M.; Varchenko, A. N.
2012
Singularities of functions, wave fronts, caustics and multidimensional integrals. Zbl 1255.58002
Arnold, V. I.; Varchenko, A. N.; Givental, A. B.; Khovanskii, A. G.
2012
Topological properties of eigenoscillations in mathematical physics. Zbl 1229.35220
Arnold, V. I.
2011
Dynamics, statistics and projective geometry of Galois fields. Zbl 1219.00001
Arnold, V. I.
2011
Vladimir I. Arnold – Collected works. Vol. I. Representations of functions, celestial mechanics, and KAM theory 1957-1965. Edited by Alexander B. Givental, Boris A. Khesin, Jerrold E. Marsden, Alexander N. Varchenko, Victor A. Vissilev, Oleg Ya. Viro and Vladimir M. Zakalyukin. Zbl 1187.01033
2010
Topological classification of Morse polynomials. Zbl 1214.57026
Arnold, V. I.
2010
Geometry of continued fractions associated with Frobenius numbers. Zbl 1201.11009
2009
Stochastic and deterministic characteristics of orbits in chaotically looking dynamical systems. Zbl 1211.37007
Arnold, V. I.
2009
Lengths of periods of continued fractions of square roots of integers. Zbl 1208.11013
2009
Permutations. Zbl 1230.05283
Arnold, V. I.
2009
Empirical study of stochasticity for deterministic chaotical dynamics of geometric progressions of residues. Zbl 1184.37011
2009
Uniform distribution of non-divisible vectors in an integer space. Zbl 1241.11088
Arnold, V. I.
2009
Nikolai Nikolaevich Nekhoroshev (obituary). Zbl 1175.01064
Abramov, A. M.; Arnol’d, V. I.; Bolsinov, A. V.; Varchenko, A. N.; Galgani, L.; Zhilinskii, B. I.; Il’yashenko, Yu. S.; Kozlov, Valerii V.; Neishtadt, Anatolii I.; Piterbarg, Vladimir I.; Khovanskii, Askold G.; Yashchenko, Valerii V.
2009
Orbits’ statistics in chaotic dynamical systems. Zbl 1161.37039
Arnold, V.
2008
Statistics of the periods of continued fractions for quadratic irrationals. Zbl 1152.11002
Arnol’d, V. I.
2008
Statistics of the period lengths of the continued fractions for the eigenvalues of the integer matrices of order two. Zbl 1178.15018
2008
Topological classification of Morse functions and generalisations of Hilbert’s 16-th problem. Zbl 1149.57044
2007
Arithmetical turbulence of selfsimilar fluctuations statistics of large Frobenius numbers of additive semigroups of integers. Zbl 1232.11046
Arnold, V.
2007
Continued fractions of square roots of rational numbers and their statistics. Zbl 1147.11036
Arnol’d, V. I.
2007
Topological classification of trigonometric polynomials related to the affine Coxeter group $$\widetilde A_2$$. Zbl 1196.58004
Arnold, V. I.
2007
Mathematical aspects of classical and celestial mechanics. Transl. from the Russian by E. Khukhro. 3rd revised ed. Zbl 1105.70002
2006
Geometry and growth rate of Frobenius numbers of additive semigroups. Zbl 1141.11020
Arnold, V. I.
2006
Forgotten and neglected theories of Poincaré. Zbl 1165.01013
Arnol’d, V. I.
2006
Complexity of finite sequences of zeros and ones and geometry of finite spaces of functions. Zbl 1196.11033
2006
Smooth functions statistics. Zbl 1154.26018
2006
On the matricial version of Fermat-Euler congruences. Zbl 1168.05003
Arnold, V. I.
2006
Statistics of the symmetric group representations as a natural science question on asymptotics of Young diagrams. Zbl 1171.20305
2006
From Hilbert’s superposition problem to dynamical systems. Zbl 1096.01007
Arnold, V. I.
2006
Statistics of Young diagrams of cycles of dynamical systems for finite tori automorphisms. Zbl 1124.05096
Arnold, V.
2006
Lobachevsky triangle altitudes theorem as the Jacobi identity in the Lie algebra of quadratic forms on symplectic plane. Zbl 1092.53055
Arnold, V.
2005
Number-theoretical turbulence in Fermat-Euler arithmetics and large Young diagrams geometry statistics. Zbl 1134.11344
Arnold, V.
2005
Ergodic and arithmetical properties of geometrical progression’s dynamics and of its orbits. Zbl 1089.11004
Arnold, V.
2005
On the topology of the eigenfields. Zbl 1134.35300
2005
Arnold’s problems. Translated and revised edition of the 2000 Russian original. Zbl 1051.00002
2004
Lectures on partial differential equations. (Vorlesungen über partielle Differentialgleichungen. Übersetzt aus dem Russischen von Tobias Damm.) Zbl 1076.35001
Arnold, V. I.
2004
Fermat dynamics, matrix arithmetics, finite circles, and finite Lobachevsky planes. Zbl 1125.11066
Arnold, V. I.
2004
Lectures on partial differential equations. Transl. from the Russian by Roger Cooke. Zbl 1076.35002
2004
The matrix Euler-Fermat theorem. Zbl 1167.11300
Arnol’d, V. I.
2004
Geometry and dynamics of Galois fields. Zbl 1148.37301
Arnol’d, V. I.
2004
Ol’ga Aleksandrovna Ladyzhenskaya (obituary). Zbl 1062.01503
Arnol’d, V. I.; Birman, M. Sh.; Vershik, A. M.; et al.
2004
From Hilbert’s superposition problem to dynamical systems. Zbl 1187.01024
Arnol’d, V. I.
2004
Abel’s theorem in problems and solutions. Based on the lectures of Professor V. I. Arnold. With a preface and an appendix by Arnold and an appendix by A. Khovanskii. Zbl 1065.12001
Alekseev, V. B.
2004
Arithmetics of binary quadratic forms, symmetry of their continued fractions and geometry of their de Sitter world. Zbl 1044.11016
Arnold, V.
2003
The topology of algebra: Combinatorics of squaring. Zbl 1040.05015
Arnold, V. I.
2003
Fermat-Euler dynamical systems and the statistics of arithmetics of geometric progressions. Zbl 1038.11006
Arnold, V. I.
2003
Aleksej Vasil’evich Pogorelov (obituary). Zbl 1050.01509
Aleksandrov, V. A.; Arnol’d, V. I.; Borisenko, A. A.; et al.
2003
Frequent representations. Zbl 1075.20004
Arnold, V. I.
2003
Topology and statistics of formulas of arithmetic. Zbl 1124.11304
Arnol’d, V. I.
2003
Optimization in mean and phase transitions in controlled dynamical systems. Zbl 1057.49003
Arnol’d, V. I.
2002
Pseudoquaternion geometry. Zbl 1039.53082
Arnol’d, V. I.
2002
Astroidal geometry of hypercycloids and the Hessian topology of hyperbolic polynomials. Zbl 1058.58018
Arnol’d, V. I.
2001
Dynamical systems. IV. Symplectic geometry and its applications. Transl. from the Russian by G. Wassermann. 2nd, expanded and revised ed. Zbl 1048.00010
2001
Lagrangian Grassmannian of a quaternion hypersymplectic space. Zbl 1034.53081
Arnol’d, V. I.
2001
On teaching mathematics. Zbl 1242.00021
2001
Complexification of tetrahedron and pseudo-projective transformations. Zbl 0999.51001
Arnold, V. I.
2001
Mathematics: frontiers and perspectives. Zbl 1047.00015
2000
Symplectic geometry and topology. Zbl 1021.53053
Arnold, V. I.
2000
The complex Lagrangian Grassmannian. Zbl 0996.53051
Arnold, V. I.
2000
Polymathematics: is mathematics a single science or a set of arts? Zbl 0980.00004
Arnold, V. I.
2000
Arnold’s problems. (Zadachi Arnol’da.) Zbl 1052.00003
Arnol’d, V. I.
2000
Dynamical systems. Zbl 0963.37003
2000
From averaging to statistical physics. Zbl 1034.82001
Arnol’d, V. I.
2000
Euler, Bernoulli and Springer numbers for Coxeter groups and Morse spaces: snake calculus. (Nombres d’Euler, de Bernoulli et de Springer pour les groupes de Coxeter et les espaces de morsification: le calcul des serpents.) Zbl 1080.05501
2000
Weak asymptotics for the numbers of solutions of Diophantine problems. Zbl 1042.11064
Arnol’d, V. I.
1999
Bifurcation theory and catastrophe theory. Translated from the 1986 Russian original by N. D. Kazarinoff. Reprint of the original English edition from the series Encyclopaedia of Mathematical Sciences (Dynamical systems V), 5 (1994). Zbl 1038.37500
Arnold, V. I.; Afraĭmovich, V. S.; Il’yashenko, Yu. S.; Shil’nikov, L. P.
1999
Simple singularities of curves. Zbl 0991.32015
Arnol’d, V. I.
1999
From Hilbert’s superposition problem to dynamical systems. Zbl 0967.01012
Arnold, V. I.
1999
Symplectization, complexification and mathematical trinities. Zbl 0948.01012
Arnold, V. I.
1999
First steps of local contact algebra. Zbl 1031.53110
Arnold, V. I.
1999
Ergodic problems of classical mechanics. Transl. from the French and the English by A. V. Borisov, Yu. A. Danilov, A. V. Letchikov, I. S. Mamaev. (Ѐргодические проблемы классической механики.) Zbl 0974.70003
Arnold, V. I.; Avez, A.
1999
First step of local symplectic algebra. Zbl 0970.57015
Arnold, V. I.
1999
Relatives of the quotient of the complex projective plane by the complex conjugation. Zbl 0963.53023
Arnold, V. I.
1999
Pseudoperiodic topology. With a preface (ix–xii) by V. I. Arnold. Zbl 0931.00017
1999
Topological problems of the theory of asymptotic curves. Zbl 1010.37012
Arnold, V. I.
1999
Selected works. Appendix: Reminiscences of V. A. Rokhlin by V. I. Arnol’d, A. M. Vershik, S. P. Novikov and Ya. G. Sinaĭ. With commentaries on Rokhlin’s work by N. Yu. Netsvetaev and Vershik. Edited and with a preface by Vershik. (Избранные работы. Воспоминания о В. А. Рохлине.) Zbl 1206.01078
Rokhlin, V. A.
1999
Topological problems in wave propagation theory and topological economy principle in algebraic geometry. Zbl 0946.01011
Arnold, V. I.
1999
Topological methods in hydrodynamics. Zbl 0902.76001
Arnold, V. I.; Khesin, B. A.
1998
Higher dimensional continued fractions. Zbl 1044.11596
Arnold, V. I.
1998
Singularity theory I. Transl. from the Russian by A. Iacob. 2nd printing of the 1st ed. 1993. Zbl 0901.58001
Arnold, V. I.; Goryunov, V. V.; Lyashko, O. V.; Vasil’ev, V. A.
1998
On teaching mathematics. Zbl 1114.00300
Arnold, V. I.
1998
On the problem of realization of a given Gaussian curvature function. Zbl 0935.53001
1998
Towards the Legendre Sturm theory of space curves. Zbl 0973.53505
Arnold, V. I.
1998
Mathematical problems of hydrodynamics and magnetohydrodynamics. (Problèmes mathématiques de l’hydrodynamique et de la magnétohydrodynamique.) Zbl 0999.76003
1998
Mathematical aspects of classical and celestial mechanics. Transl. from the Russian by A. Iacob. 2nd printing of the 2nd ed. 1993. Zbl 0885.70001
Arnold, V. I.; Kozlov, V. V.; Neishtadt, A. I.
1997
Ordinary differential equations and smooth dynamical systems. Transl. from the Russian by E. R. Dawson and D. O’Shea. 3rd printing of the 1st ed. 1988. Zbl 0858.34001
Anosov, D. V.; Aranson, S. Kh.; Arnold, V. I.; Bronshtein, I. U.; Grines, V. Z.; Il’yashenko, Yu. S.
1997
Remarks on the parabolic curves on surfaces and on the higher-dimensional Möbius-Sturm theory. Zbl 0973.53504
Arnold, V. I.
1997
Topological classification of real trigonometric polynomials and cyclic serpents polyhedron. Zbl 0904.58007
Arnold, V.
1997
Separated Dirac operators and asymptotically constant linear systems. Zbl 0902.34073
Arnold, V.; Kalf, H.; Schneider, A.
1997
Remarks concerning the Morse theory of a divergence-free vector field, the averaging method, and the motion of a charged particle in a magnetic field. Zbl 0923.58010
Arnol’d, V. I.
1997
The Arnold-Gelfand mathematical seminars. Zbl 0857.00029
1997
Lectures on partial differential equations. Second edition. (Lektsii ob uravneniyakh s chastnymi proizvodnymi.) Zbl 1055.35500
Arnol’d, V. I.
1997
Topological classification of trigonometric polynomials and combinatorics of graphs with an equal number of vertices and edges. Zbl 0898.32019
Arnold, V. I.
1996
On the number of flattening points on space curves. Zbl 0973.53502
Arnold, V.
1996
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text:
# Guardian (Chambers of Xeric)

Guardian
Released5 January 2017 (Update)
MembersYes
Combat levelN/A[1]
ExamineA guardian statue carved from the rock.
Combat info
AttributeXerician
XP bonus+7.5%
Max hit20
AggressiveYes
PoisonNo
Attack styleMelee
Attack speed
Combat stats
25014014010011
Aggressive stats
+0+20+0+0+0+0
Defensive stats
+80+180-10+0+0
Immunities
PoisonNot immune
VenomNot immune
Monster ID7569, 7571

Guardians are statues which appear in groups of two as a boss room in the Chambers of Xeric. These statues must be destroyed in order to pass the room, and can only be harmed with pickaxes; all other sources of damage will not count. The dragon warhammer's special attack applies before the attack's damage roll is reduced to zero.[2] Damage done to the guardians is multiplied by a factor as shown in fig.1.[3] The formula is capped to ensure the Crystal pickaxe deals the same damage as the Dragon pickaxe, despite having a higher mining level requirement.[4] Attempting to enter the passage they are guarding will result in the guardian knocking the player back for moderate damage.

Players attacking the guardian statues.

The guardians attack with Melee and can occasionally stomp the ground, dealing moderate to heavy damage in a 3x3 area. Due to the guardians' stomping attack, it is highly recommended to flinch them to reduce the amount of damage taken. This can be done by attacking the guardian and immediately running 3-4 spaces away, waiting until its health bar disappears and repeating.

The strengths and hit points of the guardian is dependent on the party size. The Hp formula is shown in fig.2.

{\displaystyle {\begin{aligned}D&={\frac {(50+M+P)}{150}}&&(1)\\H&=151\times (1+\lfloor T\times {\frac {1}{2}}\rfloor )+\lfloor {\overline {M}}\rfloor \times T&&(2)\end{aligned}}}

Where D is the damage multiplier, H is the guardian's hitpoints, P is the pickaxe's level requirement, M is mining level, M is the average mining level and T is team size.

## Drops

Item Quantity Rarity Price High Alch
Buchu seed3–5AlwaysNot sold3–5
Golpar seed3–5AlwaysNot sold3–5
Noxifer seed3–5AlwaysNot sold3–5

## References

1. DISCLAIMER: The stats displayed on this page can vary based on the player with the highest combat level. The stats shown are scaled for a player with maxed combat stats.
2. Jagex. Mod Ash's Twitter account. 13 April 2018. (Archived from the original on 3 September 2021.) Mod Ash: "It should apply its special effect before the roll gets changed to zero."
3. Jagex. Mod Ash's Twitter account. 15 June 2018. (Archived from the original on 28 May 2020.) Mod Ash: "The damage modifier is ((50 + Mining level + pickaxes's level req) / 150). That's applied to whatever damage you rolled; Void would have been factored in before this calculation occurs."
4. Jagex. Mod Ash's Twitter account. 29 July 2019. (Archived from the original on 28 May 2020.) Mod Ash: "The code was changed to cap it so that no new pick will be better than dragon ones."

format: plain


text:
# Thread: [Matrices Inverses] Finding the inverse equality to I doesn't work

1. ## [Matrices Inverses] Finding the inverse equality to I doesn't work

2. Hello, Cthul!

What doesn't work?

Find the inverse of: . $\begin{bmatrix}\text{-}2&\text{-}7 \\ 1&4\end{bmatrix}$

. . $(A)\;\begin{bmatrix}4&7\\ \text{-}1&\text{-}2\end{bmatrix}\qquad (B)\;\begin{bmatrix}\text{-}2&1\\7&\text{-}4\end{bmatrix} \qquad (C)\;\begin{bmatrix}\text{-}4&\text{-}7 \\ 1 & 2 \end{bmatrix}$ . . $(D)\;\begin{bmatrix}1 & \text{-}7 \\ 2&\text{-}4\end{bmatrix}\qquad (E)\;\begin{bmatrix}\text{-}1 & 2 \\ 4&\text{-}7\end{bmatrix}$

Answer (C) works . . . check it out!

3. It makes $\begin{bmatrix}1&0 \\ 0&1\end{bmatrix}$
I tried finding an inverse.
I got:
$\frac{1}{15}\begin{bmatrix}4&1 \\ \text{-}7&\text{-}2\end{bmatrix}$ $\begin{bmatrix}1&0 \\ 0&1\end{bmatrix}=A$
How'd you find it works for C?

EDIT: I see what I did wrong now, nevermind. I know how to do it now.


text:
# writing std::map to file?

This topic is 4402 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

## Recommended Posts

Hello all. I'm using a map type from the C standard library to store contents of an options file. Specifically, my problem is writing its contents back to a file. The std::map does not seem to have a way of iteratively accessing its contents for writing back to the file. If I remember correctly, std::map sorts by key on insertions so it would make sense not to be able to access its members in this way. So my question is, how can I dump the contents of the std::map to a text file without considering specific key names? I've looked over the iterators it uses, I did not see (or may have missed) any way to get from one item to the next. I thought at first by getting an iterator to the beginning of the map would be the key to going through it all, but the things I tried did not seem to work. If it helps, I am using the implementation provided with MS Visual C++ 6.0

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I just found this code snippet here. Below are the relevant parts..

#include <map>#include <string>#include <iostream>using namespace std;int main(){    map<char,string> mymap;    map<char,string>::iterator iter;    string s1 = "This";    string s2 = "is";    string s3 = "an";    string s4 = "example";    string s5 = "string";    mymap[s1[0]] = s1;    mymap[s2[0]] = s2;    mymap[s3[0]] = s3;    mymap[s4[0]] = s4;    mymap[s5[0]] = s5;    // Here is the output of the map in order from beginning to end    cout << "This is the output of the map in order" << endl;    for(iter = mymap.begin(); iter != mymap.end(); iter++)    {        cout << (*iter).first << " is the first character in the word " << iter->second << endl;        }}

Hope this helps.

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Why would it make sense for a map not to support iterators just because it's key - sorted?

std::map::iterator mIter works just fine.

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Quote:
 The std::map does not seem to have a way of iteratively accessing its contents for writing back to the file.

Sure it does; it offers an iterator interface just like any other container in the Standard library:
std::map<int, std::string> map;map[2] = "foo";map[65] = "bar";map[31] = "baz";for(std::map<int, std::string>::iterator i = map.begin(); i != map.end(); ++i)  std::cout << i->first << ": " << i->second << '\n';

outputs:
2: foo31: baz65: bar

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Just use copy with an ostream_iterator defined in <iterators>. It's basically an insert interator for an output stream.

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Even though being a very idiomatic approach, it has a drawback: std::map<>::value_type (that is, std::pair<>) doesn't have a stream insertion operator defined! So, before it works, you have to write the overload yourself, and insert it into namespace std! Otherwise, the overload resolution (Koenig lookup) isn't going to find it (*.

*) I'm not completely sure about this - it may be that gcc has a bug or a "feature" in their implementation of ADL. Either way, even if your compiler finds the operator in global namespace, the code won't be portable to gcc, at least for the time being.

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Quote:
 Original post by LilBudyWizerJust use copy with an ostream_iterator defined in . It's basically an insert interator for an output stream.

Can't do.

Use std::transform and write yourself a functor to output the pair::second value to the std::ostream_iterator (or std::ostreambuf_iterator).


text:
# Minimizing mutual information using Lagrange multipliers

Im trying to follow a minimization of mutual information using Lagrange multipliers in a highly cited paper called The Information Bottleneck Method (1999), page 4:

$$R(D) = \min_{p(\tilde{x}|x): E[d(x,\tilde{x})]\leq D} I(X,\tilde{X})$$

Where $X$ is a given random variable and $\tilde{X}$ is a compressed representation of it. The constraint is just an expectation of a distortion function $d(\cdot,\cdot)$, that gives the difference between two realizations of the r.v.s. The mutual information is defined as $I(X;\tilde{X}) =\sum_{x\in X}\sum_{\tilde{x}\in\tilde{X}} p(x,\tilde{x})\log\frac{p(\tilde{x}|x)}{p(\tilde{x})}$ and $E[d(x,\tilde{x})] = \sum_x\sum_\tilde{x} p(x,\tilde{x})d(x,\tilde{x})$

The functional to minimize is written as: $$\mathcal{F}[p(\tilde{x}|x)]=I(X;\tilde{X}) +\beta E[d(x,\tilde{x})]$$ Where $\beta$ is a Lagrange multiplier.

The paper continues with the derivative $\frac{\partial \mathcal{F}}{\partial p(\tilde{x}|x)}=0$ and thats the step I don't understand how to follow. It says: $$\frac{\partial \mathcal{F}}{\partial p(\tilde{x}|x)}=p(x)\left[\log\frac{p(\tilde{x}|x)}{p(\tilde{x})}+1-\frac{1}{p(\tilde{x})}\sum_{x^\prime}p(x^\prime)p(\tilde{x}|x^\prime) + \beta d(x,\tilde{x})+\frac{\lambda(x)}{p(x)}\right]$$

It says "$\lambda(x)$ are the normalization Lagrange multipliers for each $x$".

Questions: what are a normalization Lagrange multiplier? I dont know where that sum comes from, it only says after "since the marginal distribution satisfies $p(\tilde{x})=\sum_{x^\prime}p(x^\prime)p(\tilde{x}|x^\prime)$" (which is a condition that appeared before, but I dont know why is doing here).

PS: I tried to follow the process in this presentation, slide 19-20, but again, I dont understand how to derive the expression...

Thanks a lot beforehand.

• I interpret it as the marginal distribution of your required conditional distribution $p(\tilde{x}|x)$ must be induced by the original distribution $p(x)$. This may sound like a stupid redundant constraint, but in fact there ARE possible solutions whose marginals are NOT directly induced by $p(x)$ in this manner. This would be undesirable, and may possibly even make the solution set non-unique. Jan 21, 2016 at 7:38


text:
# Limit of the Integral Sum

1. Aug 7, 2005

### siddharth

To integrate functions as the limit of an integral sum, how can we know which way to take the partition points in the interval?

For example, in
$$\int_{a}^{b} x dx$$

I can take the partition points as

$$x_o = a$$
$$x_1 = a + \delta x$$
...
$$x_k = a+ k\delta x$$
where $$\delta x = \frac{b-a}{n}$$

So that the sum is $$\sum_{k=1}^{n} f(x_{k-1}) \delta x$$

But to integrate
$$\int_{a}^{b} \sqrt{x} dx$$

If I take the partition points as above the sum will be
$$(\delta x)(\sqrt{a} + \sqrt{a+ \delta x} + ... )$$

which I cannot find.

I can solve the question if I take the partition points as
$$x_0 = a$$
$$x_1 = aq$$
...
$$x_k=aq^k$$

Where $$q=(\frac{b}{a})^(1/n)$$.
{The idea to take it this way was given as a hint in the book}

So, is there any other specific manner in which I should spilt the partition points and if so is there a general method in which I can know how to take the values of x_0, x_1, x_2 to solve the problem?

2. Aug 7, 2005

### matt grime

the choice of partition depends upon the function. experience is the thing you need and an educated guess. Ideally you want to choose the partition such that the resulting series is one you can sum. egn if tou wre doing sqrt(x) from 0 to 1 then picking the partition i^2/n^2 as i goes from 0 to n is good cos the square root spits out i/n.

Last edited: Aug 7, 2005
3. Aug 7, 2005

### HallsofIvy

Are you talking about a numerical integration? In that case, there are two things you can do:(1) take the points equally spaced so the calculations are easier or (2) take the points closer together where the function changes rapidly (i.e. where the derivative is large) so that the integration is more accurate.

Of course, if you are talking about the Riemann sums used to define the integral, then it doesn't matter. As long as the function is integrable, any partition will give the same answer.

4. Aug 7, 2005

### matt grime

Ah, but proving that something is riemann integrable by the criterion of integrability requiers you to chose the partition family intellignetly, in my experience of teaching analysis. actually to be honest, for any example in the course or the exam there was always a strongly suggested hint.

the approximate rules is pick a partiiton so that the length of the interval and the max.min value spat out are such that when you multiply them together you are addding up r^k from 1 to n times some constant and then appeal to seom result about summing these series.

of course the sensilbe person simply cites that any continuous or montone function is riemann integrable.


text:
# Chapter 19 - Problems - Page 753: 30

$m = 2.6\times 10^{-25}~kg$

#### Work Step by Step

We can find an expression for the speed $v$: $\frac{mv^2}{r} = qvB$ $v = \frac{q~B~r}{m}$ The particle has a kinetic energy of $q~\Delta V$. We can find the mass $m$: $K = q~\Delta V$ $\frac{1}{2}mv^2 = q~\Delta V$ $\frac{1}{2}(m)(\frac{q~B~r}{m})^2 = q~\Delta V$ $m = \frac{q~B^2~r^2}{2~\Delta V}$ $m = \frac{(1.6\times 10^{-19}~C)~(1.2~T)^2~(0.125~m)^2}{(2)~(7000~V)}$ $m = 2.6\times 10^{-25}~kg$

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.


text:
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By default, OpenID may be used for both registration and logins. If you do not wish to make OpenID facilities available on your system (at all), set 'no_openid' to true. Default is false.

#### Multiple Registrations

The ability to create "Pages" requires a person to register more than once. Your site configuration can block registration (or require approval to register). By default, logged in users can register additional accounts for use as pages. These will still require approval if the registration policy is set to require approval You may prohibit logged in users from creating additional accounts by setting block multible registrations to true. Default is false.

#### Maximum Image Size

Maximum size in bytes of uploaded images. The default is set to 0, which means no limits.

### Policies

#### Global Directory

This configures the URL to update the global directory, and is supplied in the default configuration. The undocumented part is that if this is not set, the global directory is completely unavailable to the application. This allows a private community to be completely isolated from the global network.

#### Force Publish

By default, each user can choose on their Settings page whether or not to have their profile published in the site directory. This setting forces all profiles on this site to be listed in the site directory and there is no option provided to the user to change it. Default is false.

#### Block Public

Set to true to block public access to all otherwise public personal pages on this site unless you are currently logged in. This blocks the viewing of profiles, friends, photos, the site directory and search pages to unauthorised persons. A side effect is that entries from this site will not appear in the global directory. We recommend specifically disabling that also (setting is described elsewhere on this page). Note: this is specifically for sites that desire to be "standalone" and do not wish to be connected to any other Friendica sites. Unauthorised persons will also not be able to request friendship with site members. Default is false. Available in version 2.2 or greater.

#### Allowed Friend Domains

Comma separated list of domains which are allowed to establish friendships with this site. Wildcards are accepted. (Wildcard support on Windows platforms requires PHP5.3). By default, any (valid) domain may establish friendships with this site.

This is useful if you want to setup a closed network for educational groups, cooperations and similar communities that don't want to commuicate with the rest of the network.

#### Allowed Email Domains

Comma separated list of domains which are allowed in email addresses for registrations to this site. This can lockout those who are not part of this organisation from registering here. Wildcards are accepted. (Wildcard support on Windows platforms requires PHP5.3). By default, any (valid) email address is allowed in registrations.

#### Allow Users to set remote_self

If you enable the Allow Users to set remote_self users can select Atom feeds from their contact list being their remote self in the advanced contact settings. Which means that postings by the remote self are automatically reposted by Friendica in their names.

This feature can be used to let the user mirror e.g. blog postings into their Friendica postings. It is disabled by default, as it causes additional load on the server and may be misused to distribute SPAM.

As admin of the node you can also set this flag directly in the database. Before doing so, you should be sure you know what you do and have a backup of the database.

#### Proxy Configuration Settings

If your site uses a proxy to connect to the internet, you may use these settings to communicate with the outside world. The outside world still needs to be able to see your website, or this will not be very useful.

#### Network Timeout

How long to wait on a network communication before timing out. Value is in seconds. Default is 60 seconds. Set to 0 for unlimited (not recommended).

#### Verify SSL Certitificates

By default Friendica allows SSL communication between websites that have "self-signed" SSL certificates. For the widest compatibility with browsers and other networks we do not recommend using self-signed certificates, but we will not prevent you from using them. SSL encrypts all the data transmitted between sites (and to your browser). This allows you to have completely encrypted communications, and also protect your login session from hijacking. Self-signed certificates can be generated for free, without paying top-dollar for a website SSL certificate. However these aren't looked upon favourably in the security community because they can be subject to so-called "man-in-the-middle" attacks. If you wish, you can turn on strict certificate checking. This will mean you cannot connect (at all) to self-signed SSL sites.

### Worker

This section allows you to configure the background process that is triggered by the cron job that was created during the installation. The process does check the available system resources before creating a new worker for a task. Because of this, it may happen that the maximum number of worker processes you allow will not be reached.

If your server setup does not allow you to use the proc_open function of PHP, please disable it in this section.

The tasks for the background process have priorities. To guarantee that important tasks are executed even though the system has a lot of work to do, it is useful to enable the fastlane.

Should you not be able to run a cron job on your server, you can also activate the frontend worker. If you have done so, you can call example.com/worker (replace example.com with your actual domain name) on a regular basis from an external servie. This will then trigger the execution of the background process.

## Users

This section of the panel let the admin control the users registered on the node.

If you have selected "Requires approval" for the Register policy in the general nodes configuration, new registrations will be listed at the top of the page. There the admin can then approve or disapprove the request.

Below the new registration block the current accounts on the Friendica node are listed. You can sort the user list by name, email, registration date, date of last login, date of last posting and the account type. Here the admin can also block/unblock users from accessing the node or delete the accounts entirely.

In the last section of the page admins can create new accounts on the node. The password for the new account will be send by email to the choosen email address.

## Plugins

This page is for selecting and configuration of extensions for Friendica which have to be placed into the /addon subdirectory of your Friendica installation. You are presented with a long list of available addons. The name of each addon is linked to a separate page for that addon which offers more informations and configuration possibilities. Also shown is the version of the addon and an indicator if the addon is currently active or not.

When you update your node and the addons they may have to be reloaded. To simplify this process there is a button at the top of the page to reload all active plugins.

## Themes

The Themes section of the admin panel works similar to the Plugins section but let you control the themes on your Friendica node. Each theme has a dedicated subpage showing the current status, some information about the theme and a screen-shot of the Friendica interface using the theme. Should the theme offer special settings, admins can set a global default value here.

You can activate and deactivate themes on their dedicated sub-pages thus making them available for the users of the node. To select a default theme for the Friendica node, see the Site section of the admin panel.

There are several optional features in Friendica like the dislike button. In this section of the admin panel you can select a default setting for your node and eventually fix it, so users cannot change the setting anymore.

Should the database structure of Friendica change, it will apply the changes automatically. In case you are suspecious that the update might not have worked, you can use this section of the admin panel to check the situation.

## Inspect Queue

In the admin panel summary there are two numbers for the message queues. The second number represents messages which could not be delivered and are queued for later retry. If this number goes sky-rocking you might ask yourself which receopiant is not receiving.

Behind the inspect queue section of the admin panel you will find a list of the messages that could not be delivered. The listing is sorted by the receipiant name so identifying potential broken communication lines should be simple. These lines might be broken for various reasons. The receiving end might be off-line, there might be a high system load and so on.

Don't panic! Friendica will not queue messages for all time but will sort out dead nodes automatically after a while and remove messages from the queue then.

## Server Blocklist

This page allows to block all communications (inbound and outbound) with a specific domain name. Each blocked domain entry requires a reason that will be displayed on the friendica page. Matching is exact, blocking a domain doesn't block subdomains.

## Federation Statistics

The federation statistics page gives you a short summery of the nodes/servers/pods of the decentralized social network federation your node knows. These numbers are not compleate and only contain nodes from networks Friendica federates directly with.

## Delete Item

Using this page an admin can delete postings and eventually associated discussion threads from their Friendica node. To do so, they need to know the GUID of the posting. This can be found on the /display page of the posting, it is the last part of the URL displayed in the browsers navigation bar. You can get to the /display page by following the Link to source.

## Plugin Features

Some of the addons you can install for your Friendica node have settings which have to be set by the admin. All those addons will be listed in this area of the admin panels side bar with their names.

## Logs

The log section of the admin panel is seperated into two pages. On the first, following the "log" link, you can configure how much Friendica shall log. And on the second you can read the log.

You should not place your logs into any directory that is accessible from the web. If you have to, and you are using the default configuration from Apache, you should choose a name for the logfile ending in .log or .out. Should you use another web server, please make sure that you have the correct accessrules in place so that your log files are not accessible.

There are five different log levels: Normal, Trace, Debug, Data and All. Specifying different verbosities of information and data written out to the log file. Normally you should not need to log at all. The DEBUG level will show a good deal of information about system activity but will not include detailed data. In the ALL level Friendica will log everything to the file. But due to the volume of information we recommend only enabling this when you are tracking down a specific problem.

The amount of data can grow the filesize of the logfile quickly. You should set up some kind of log rotation to keep the log file from growing too big.

Known Issues: The filename friendica.log can cause problems depending on your server configuration (see issue 2209).

By default PHP warnings and error messages are supressed. If you want to enable those, you have to activate them in the .htconfig.php file. Use the following settings to redirect PHP errors to a file.

Config:

error_reporting(E_ERROR | E_WARNING | E_PARSE );
ini_set('error_log','php.out');
ini_set('log_errors','1');
ini_set('display_errors', '0');

This will put all PHP errors in the file php.out (which must be writeable by the webserver). Undeclared variables are occasionally referenced in the program and therefore we do not recommend using E_NOTICE or E_ALL. The vast majority of issues reported at these levels are completely harmless. Please report to the developers any errors you encounter in the logs using the recommended settings above. They generally indicate issues which need to be resolved.

If you encounter a blank (white) page when using the application, view the PHP logs - as this almost always indicates an error has occurred.

## Diagnostics

In this section of the admin panel you find two tools to investigate what Friendica sees for certain ressources. These tools can help to clarify communication problems.

For the probe address Friendica will display information for the address provided.

With the second tool check webfinger you can request information about the thing identified by a webfinger (someone@example.com).

# Exceptions to the rule

There are four exceptions to the rule, that all the config will be read from the data base. These are the data base settings, the admin account settings, the path of PHP and information about an eventual installation of the node in a sub-directory of the (sub)domain.

## DB Settings

With the following settings, you specify the data base server, the username and passwort for Friendica and the database to use.

$db_host = 'your.db.host';$db_user = 'db_username';
$db_pass = 'db_password';$db_data = 'database_name';


text:
# Questions about Neural Network training (back propagation) in the book PRML (Pattern Recognition and Machine Learning)

I am reading Chapter 5 of PRML. Some symbols don't seem to be clear to me.

In page 243, for the chain rule for partial derivative $\dfrac{\partial E_n}{\partial w_{ji}}=\dfrac{\partial E_n}{\partial a_j}\dfrac{\partial a_j}{\partial w_{ji}}$ (equation (5.50)), a notation is defined as $\delta_j\equiv\dfrac{\partial E_n}{\partial a_j}$ (equation (5.51)). In my understanding $\delta_j$ is the first part in the chain rule. However in equation (5.54), the book mentioned

As we have seen already, for the output units, we have $$\delta_k=y_k-t_k$$

Question 1: $y_k-t_k$ is the error on output unit $k$, which is simply the difference between the $k$th output unit value and the corresponding target value. But, from the definition of the notation $\delta_k$, we should have $$\delta_k=\dfrac{\partial \frac{1}{2}(y_k-t_k)^2}{\partial a_k}=(y_k-t_k)\dfrac{\partial y_k}{\partial a_k}=(y_k-t_k)\dfrac{\partial h(a_k)}{\partial a_k}$$ where $h(a_k)$ is the activation function. So why in the book $\delta_k=y_k-t_k$??

In page 242, Section 5.3. Error Backpropagation,

Consider a simple linear model where the outputs $y_k$ are linear combinations of the input variables $x_i$ so that $y_k=\sum_iw_{ki}x_i$. For a particular input pattern $n$, the error function is $E_n=\dfrac{1}{2}\sum_k(y_{nk}-t_{nk})^2$, where $y_{nk}=y_k(\boldsymbol{x_n},\boldsymbol{w})$. So the gradient of this error function with respect to a weight $w_{ij}$ is given by $$\frac{\partial E_n}{\partial w_{ji}}=(y_{nj}-t_{nj})x_{ni}$$ which can be interpreted as a ‘local’ computation involving the product of an ‘error signal’ $y_{nj} − t_{nj}$ associated with the output end of the link $w_{ji}$ and the variable $x_{ni}$ associated with the input end of the link.

Question 2: I am not clear with the structure of this neural network. The one in the book is a two-layer neural network with linear activation, is it?

Q1: It seems here $y_k=a_k$, in PRML around eq 5.18
In the regression case, we can view the network as having an output activation function that is the identity, so that $y_k = a_k$
Consider first a simple linear model in which the outputs $y_k$ are linear combinations of the input variables $x_i$
• Q1: Isn't the activation function in the context is given in eq. 5.49, i.e., $z_j=h(a_j)$? Also in another book I'm reading Python Machine Learning - Second Edition, for a 3-layer MLP with sigmoid activation function on hidden and output units, the error vector of the output layer has a similar form: $\boldsymbol{\delta^{(out)}=a^{(out)}-y}$, where $a^{(out)}$ is the output vector and $y$ is the target vector. – Tyler 十三将士归玉门 Jul 31 '18 at 8:39
• @Tyler提督九门步军巡捕五营统领 you're right, in the first quote it mentioned the activation function used is the identity function since it's a regression task, so $h(a_j)=a_j$ :) – dontloo Jul 31 '18 at 9:05


text:
# Problem with title page when justified in Tufte-Book

I am using Tufte Book template and defined a new paper size (10x7 inches) in .def file. Its working fine. When I use justified option in preamble like:\documentclass[e1paper,symmetric,justified]{tufte-book} it justifies the whole text but the title goes out of the margin of the paper:

but I need to obtain something like this i.e. within margin range:

One solution I have found is to set the text width as:\geometry{textwidth=.55\paperwidth} but it does not look like an organised way and also the text width of whole document decreases. Another option that i think possible is to remove the justified effect from the title page and put newlines manually but still doesn't look systematic. Please suggest a solution with methodology. Thanks

• Welcome to TeX.SE. (1) It's usual here to post a minimal example of your TeX source that shows the problem; you'll get more help if you do, but make sure it's truly minimal! (2) I thought the whole point of Tufte-Book was to avoid justification, none of Tufte's books is ever justified; the theory is that you get more evenly spaced lines and it looks less formal. So I'm amazed that there is a justified option, but not surprised it doesn't work well. (3) You might find it easier to start with a simpler class, templates cause so much trouble... – Thruston May 24 '15 at 9:59

If we redefine the \maketitlepage macro to always set the title page ragged right (instead of justified), it will improve the line wrapping. Add the following to the preamble of your document (between the \documentclass and \begin{document} lines):

\renewcommand{\maketitlepage}{%
\cleardoublepage
\begin{fullwidth}%
\sffamily


text:
## Operator Algebras Seminar Fall 2015

Organizers: Marius Dadarlat, Andrew Toms, and Thomas Sinclair

Thursday, 2:30-3:30pm, MATH 731

• Date: 8/27/15
• Thomas Sinclair, Purdue University
• Title: W$^\ast$-Rigidity for the von Neumann Algebras of Products of Hyperbolic Groups
• Abstract: We show that if $\Gamma = \Gamma_1\times\cdots\times \Gamma_n$ is a product of $n\geq 2$ non-elementary ICC hyperbolic groups then any discrete group $\Lambda$ which is W$^\ast$-equivalent to $\Gamma$ decomposes as a $k$-fold direct sum exactly when $k=n$. This gives a group-level strengthening of Ozawa and Popa's unique prime decomposition theorem by removing all assumptions on the group $\Lambda$. This result in combination with Margulis' normal subgroup theorem allows us to give examples of lattices in the same Lie group which do not generate stably equivalent II$_1$ factors. This is joint work with Ionut Chifan and Rolando de Santiago.

• Date: 9/3/15
• Thomas Sinclair, Purdue University
• Title: W$^*$-Rigidity for the von Neumann Algebras of Products of Hyperbolic Groups, II
• Abstract: We show that if $\Gamma = \Gamma_1 \times\cdots\times \Gamma_n$ is a product of $n\geq 2$ non-elementary ICC hyperbolic groups then any discrete group $\Lambda$ which is W$^*$-equivalent to $\Gamma$ decomposes as a $k$-fold direct sum exactly when $k=n$. This gives a group-level strengthening of Ozawa and Popa's unique prime decomposition theorem by removing all assumptions on the group $\Lambda$. This result in combination with Margulis' normal subgroup theorem allows us to give examples of lattices in the same Lie group which do not generate stably equivalent II$_1$ factors. This is joint work with Ionut Chifan and Rolando de Santiago.

• Date: 9/10/15
• Hung-Chang Liao, Pennsylvania State University
• Title: A Rokhlin Type Theorem for Automorphisms of Simple $\mathbf C^*$-algebras of Finite Nuclear Dimension
• Abstract: Following Connes' work on automorphisms of the hyperfinite II$_1$ factor and Kishimoto's work on automorphisms of AF and $A\mathbb T$ algebras, we prove a Rokhlin type theorem for automorphisms of unital simple separable stably finite $C^*$-algebras of finite nuclear dimension. More precisely, under suitable assumptions on the trace space and/or the induced action on it, we show that strongly outer $\mathbb Z$-actions have finite Rokhlin dimension. In particular the crossed product formed by such an action has finite nuclear dimension. This result is inspired by an unpublished work of Hiroki Matui and Yasuhiko Sato.

• Date: 9/12-9/13/15

• Date: Tuesday, 9/15/15 **Colloquium, 4:30-5:30 in MATH 175**
• Joachim Zacharias, University of Glasgow
• Title: Noncommutative Generalizations of Covering Dimension
• Abstract: By a well-known slogan, which we will explain in the talk, C$^*$-algebras can be regarded as noncommutative locally compact spaces. Classical covering dimension theory is a theory of dimension for locally compact or even general topological spaces based on combinatorial properties of arbitrarily small open covers. One can think of an open cover as an approximation of the space. It has thus been an important question to define a topological dimension concept for noncommutative algebras. Several different approaches to this problem have been suggested. We will explain one such approach which is more recent and based on approximation. The resulting dimension concepts have turned out to be of great importance in the structure theory of C$^*$-algebras. There is also a dimension theory for dynamical systems which has some interesting connections to the so-called coarse geometry. We will sketch some of these developments in an elementary fashion without requiring too special background knowledge.

• Date: 9/17/15
• No Seminar due to Colloquium

• Date: 9/24/15
• Title: Deformations of groups, C$^*$-algebras and K-homology
• Abstract: Let G be a countable torsion free nilpotent group and let I(G) be the kernel of the trivial representation $\iota:C^*(G)\to \mathbb{C}$. We show that the K-homology group of I(G) is isomorphic to the homotopy classes of asymptotic homomorphisms $\{\phi_t:I(G)\to M_\infty(\mathbb{C})\}_{t\in [1,\infty)}$. This is joint work with Ulrich Pennig.

• Date: 10/1/15
• Wilhelm Winter, University of Münster
• Title: QDQ vs. UCT
• Abstract: None.

• Date: 10/3/15 - 10/4/15

• Date: 10/8/15
• Title:
• Abstract:

• Date: 10/10/15 - 10/11/15

• Date: 10/15/15

• Date: 10/22/15
• Martin Christensen, University of Copenhagen
• Title: Regularity and comparability properties of Villadsen algebras
• Abstract: In a recent article, Kirchberg and Rørdam asked the following question: Suppose that A is a unital and separable $C^*$-algebra. Does it follow that A absorbs the Jiang-Su algebra tensorially if and only if the central sequence algebra of A has no characters? Relying on work of several authors, most notably Kirchberg-Rørdam, Toms-Winter and Villadsen we show that this question has an affirmative answer when A is a unital and simple Villadsen algebras of either the first or second type. Time permitting we will also outline the construction of a Villadsen algebra of the second type which is unital, simple, separable, nuclear and has a unique tracial state and yet fails to satisfy the (strong) Corona Factorization Property.

• Date: 10/29/15
• Title:
• Abstract:

• Date: 11/5/15
• Brent Nelson, UC Berkeley
• Title: An application of free transport to mixed $q$-Gaussian algebras (joint with Qiang Zeng)
• Abstract: Given a symmetric array $Q=(q_{ij})\in M_{N\times N}([-1,1])$, Bo\.zejko and Speicher studied the commutation relation $l_i^*l_j - q_{ij}l_j l_i^*=\delta_{i=j}$ and showed it is satisfied by left creation operators $l_1,\ldots, l_N$ on a particular Fock space. Then the mixed $q$-Gaussian algebra $\Gamma_Q$, which is the von Neumann algebra generated by the operators $X_i=l_i+l_i^*$, can be thought of as a deformation of the free group factor $L(\mathbb{F}_N)$, which corresponds to the zero array. It is known that these deformations share various properties with the free group factors, and recently Guionnet and Shlyakhtenko showed that $\Gamma_Q\cong L(\mathbb{F}_N)$ when $Q=(q)$ is a constant array with $|q|$ less than a constant determined by $N$. They used a novel method called \emph{free transport} and relied on work of Dabrowski, who established that particular elements known as \emph{conjugate variables} could be represented as power series in $X_1,\ldots, X_N$ for sufficiently small $|q|$. In this talk, I will show that these techniques can be applied to a general mixed $q$-Gaussian algebra and that $\Gamma_Q\cong L(\mathbb{F}_N)$ provided $\max |q_{ij}|$ is less than a constant determined by $N$.

• Date: 11/12/15
• Dan Li, Purdue University
• Title: Topological insulators and NCG
• Abstract: Topological insulators can be characterized by a $\mathbb{Z}_2$-valued topological invariant, which is called the topological $\mathbb{Z}_2$ invariant. This mod 2 topological invariant can be understood as an index theorem with a $\mathbb{Z}_2$ symmetry. I will give some background about the index theory of the topological $\mathbb{Z}_2$ invariant, then talk about its generalizations in noncommutative geometry (NCG).

• Date: 11/19/15
• Daniel Hoff, UC San Diego
• Title: Von Neumann's Problem and Extensions of Non-Amenable Equivalence Relations
• Abstract: In 2007, Gaboriau and Lyons showed that any nonamenable group $\Gamma$ has a free ergodic pmp action $\Gamma \curvearrowright X$ whose orbit equivalence relation $\mathcal{R}(\Gamma \curvearrowright X)$ contains $\mathcal{R}(\mathbb{F}_2 \curvearrowright X)$ for some free ergodic pmp action of $\mathbb{F}_2$. This talk will focus on joint work with Lewis Bowen and Adrian Ioana in which we extend this result, showing that given any ergodic nonamenable pmp equivalence relation $\mathcal{R}$, the Bernoulli extension $\tilde{\mathcal{R}}$ over a nonatomic base space must contain $\mathcal{R}(\mathbb{F}_2 \curvearrowright \tilde{X})$ for some free ergodic pmp action of $\mathbb{F}_2$. We then show that any such $\mathcal{R}$ admits uncountably many extensions $\{\tilde{\mathcal{R}}_\alpha\}_{\alpha \in A}$ which are pairwise not stably von Neumann equivalent. From this we deduce that any nonamenable unimodular lcsc group $G$ has uncountably many free ergodic pmp actions which are pairwise not von Neumann equivalent (in particular, pairwise not orbit equivalent).

• Date: 11/26/15
• No Meeting, Thanksgiving Break.

• Date: 12/3/15
• Chenxu Wen, Vanderbilt University
• Title: Popa's AOP and amenable extensions inside II$_1$ factors
• Abstract: Popa introduced the notion of asymptotic orthogonality property (AOP) and used it to show the maximal amenability of the generator masa inside a free group factor. Since then it has become the most successful approach in studying maximal amenable subalgebras. In this talk I will explain usually how a stronger version of AOP leads to examples of unique maximal amenable extension inside II$_1$ factors.

• Date: 12/10/15
• Title:
• Abstract:

• End of Fall Semester.


text:
Browse Questions

The sum of the coefficients of the polynomial $(1+x-3x^2)^{2143}$ is

$\begin{array}{1 1}(A)\;-1\\(B)\;1\\(C)\;0\\(D)\;\text{none of these}\end{array}$

Sum of coefficients in $(1+x-3x^2)^{2143}$
$\Rightarrow (1+1-3(1)^2)^{2143}$
$\Rightarrow (-1) ^{2143}=-1$
Hence (A) is the correct answer.

+1 vote


text:
#### rsala

• Moderator
• Member
• Posts: 348
« Reply #15 on: January 27, 2014, 06:50:27 AM »
Hi,

I'm getting crazy with this. I'm terribly sorry but I can't see where the problem is so I can't fix it. Everything works fine in all computers and Windows platforms where I have tested Easy Code GoAsm.

I will keep on trying.

Ramon
EC coder

#### satpro

• Member
• Posts: 116
« Reply #16 on: January 27, 2014, 07:22:16 AM »
Hi,

I'm getting crazy with this. I'm terribly sorry but I can't see where the problem is so I can't fix it. Everything works fine in all computers and Windows platforms where I have tested Easy Code GoAsm.

I will keep on trying.

Ramon

Hi Ramon,
You know what?  Don't sweat it.  No sense getting crazy over something one person (me) is talking about.  It must be something on my end.  Just wish I knew what.  I'll code the long way and just add the headers in code -- I am used to doing that anyhow.  The IDE is nice to work with, and it's really all I was after anyway, so that's good enough.  In the meantime, if I do manage to figure out what it is I'll be sure to report back.

Bert

#### anta40

• Member
• Posts: 315
« Reply #17 on: January 27, 2014, 11:36:04 PM »
Hi,

I'm getting crazy with this. I'm terribly sorry but I can't see where the problem is so I can't fix it. Everything works fine in all computers and Windows platforms where I have tested Easy Code GoAsm.

I will keep on trying.

Ramon

Hi Ramon,

Does EasyCode have a mechanism to generate error dump?
I know that not being able to reproduce bug can be very confusing, and in this case
examining error dump can provide some hints about the bug itself.

#### rsala

• Moderator
• Member
• Posts: 348
« Reply #18 on: January 28, 2014, 06:37:09 AM »
Hi satpro,

Thanks a lot for you kind words. I'll try to find out the problem.

Ramon
EC coder

#### rsala

• Moderator
• Member
• Posts: 348
« Reply #19 on: January 28, 2014, 06:41:21 AM »
Hi anta40,

Thanks for giving ideas.

No, unfortunately Easy Code does not have any mechanism to generate error dump.

Ramon
EC coder

#### jj2007

• Member
• Posts: 12487
• Assembler is fun ;-)
« Reply #20 on: January 28, 2014, 07:28:32 AM »
No, unfortunately Easy Code does not have any mechanism to generate error dump.

A simple debug macro could do the job, applied near the code area where the problem seems to be.
This one uses a switch; if usedeb=0, no extra code will be generated. With usedeb=1, extra checks are being performed, and a console window will be created to display the error line:
Code: [Select]
`include \masm32\include\masm32rt.incusedeb=1 ; 0=no checks, 1=checkvoidNonZero MACRO argsLOCAL tmp\$  @CatStr(<;>, <args>)  if usedeb .if !eax pushad invoke GetConsoleWindow .if !eax ; must be SUBSYSTEM:WINDOWS... invoke AllocConsole .endif tmp\$ CATSTR <chr\$("## eax is zero in line >, %@Line, < ##")> print tmp\$, 13, 10 popad .endif  endifENDM.datarc RECT <>hWin dd ?.codestart: voidNonZero rv(GetConsoleWindow) ; uses Masm32 rv macro invoke GetClientRect, edx, addr rc voidNonZero eax ; more traditional voidNonZero rv(GetClientRect, eax, addr rc) MsgBox 0, str\$(rc.right), "Pixels wide:", MB_OK exitend start`

#### rsala

• Moderator
• Member
• Posts: 348
« Reply #21 on: January 28, 2014, 08:15:11 AM »
Hi jj2007,

Thank you very much!

I will test the macro.

Ramon
EC coder

#### satpro

• Member
• Posts: 116
« Reply #22 on: January 30, 2014, 08:15:03 AM »
I would like to announce that Ramon has taken the steps to fix my problem with adding include files through Project Explorer/Menu.  He did it in a professional, unrelenting manner (through personal messaging) that has left me impressed to the point of bewilderment.

Just thought everyone should know.

Thanks Ramon.  You're a class act for sure.

• Moderator
• Member
• Posts: 348


text:
# How to interpret a significant effect present in a subset data but absent in the full data

My model has 3 predictors:

1. Group (A vs. B)
2. Condition (baseline vs. treatment)
3. Memory (a continuous variable)

The model gives an interaction between Condition and Group.

I then tested the simple effect of Condition within each level of Group, by subsetting the data by Group and build models on the subset data. The model for Group A shows an interaction between Condition and Memory.

My question is how I should interpret the interaction between Condition and Memory, given that in the full model there is no effect involving Memory, and simple effect doesn't aim to test Memory?

Here is the data data.

Here is the code:

> # read in data
> df <- read.csv(file = "data/df.csv")
>
> # orthogonal contrasts
> contrasts(df$$Group) <- c(-1/2, 1/2) > contrasts(df$$Condition) <- c(-1/2, 1/2)
>
> # build model
> mod <- lmer(score ~ Condition * Group * Memory + (1|SubjID), data = df)
> Anova(mod, type = "III")
Analysis of Deviance Table (Type III Wald chisquare tests)

Response: score
Chisq Df Pr(>Chisq)
(Intercept)            30.5590  1  3.239e-08 ***
Condition               6.1629  1    0.01305 *
Group                  20.5651  1  5.764e-06 ***
Memory                  1.2731  1    0.25918
Condition:Group        25.0994  1  5.445e-07 ***
Condition:Memory        1.9954  1    0.15777
Group:Memory            3.0044  1    0.08304 .
Condition:Group:Memory  2.8056  1    0.09393 .
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
>
> # simple effect: subsetting Group A
> df <- df %>% filter(Group == "A") %>% droplevels()
> # orthogonal contrasts
> contrasts(df\$Condition) <- c(-1/2, 1/2)
> # model
> mod <- lmer(score ~ Condition * Memory + (1|SubjID), data = df)
> Anova(mod, type = "III")
Analysis of Deviance Table (Type III Wald chisquare tests)

Response: score
Chisq Df Pr(>Chisq)
(Intercept)      59.4346  1  1.264e-14 ***
Condition        25.5871  1  4.229e-07 ***
Memory            4.6007  1    0.03196 *
Condition:Memory  4.1592  1    0.04141 *
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

The global effects are not significant, but when you drop the Group variable (by choosing only A), the effect is apparent in this group. I would expect that the group B does not have these significant "simple" effects (or as the opposite effect) as to balance the results to be non significant.
These results is somewhat hidden from the marginal (close to significant) effects Condition:Memory and Condition:Group:Memory, which suggest that a phenomenon might occur, but too weakly to be perceived in the complete model.
If the effect Condition:Memory is relevant, you can interpret it and pointing out that controlling for Group lead to a non significant "global" result.