private void adjustMarkerHeights() {
		double mm = _n[1] - 1.0;
		double mp = _n[1] + 1.0;
		if (_nn[0] >= mp && _n[2] > mp) {
			_q[1] = qPlus(mp, _n[0], _n[1], _n[2], _q[0], _q[1], _q[2]);
			_n[1] = mp;
		} else if (_nn[0] <= mm && _n[0] < mm) {
			_q[1] = qMinus(mm, _n[0], _n[1], _n[2], _q[0], _q[1], _q[2]);
			_n[1] = mm;
		}

		mm = _n[2] - 1.0;
		mp = _n[2] + 1.0;
		if (_nn[1] >= mp && _n[3] > mp) {
			_q[2] = qPlus(mp, _n[1], _n[2], _n[3], _q[1], _q[2], _q[3]);
			_n[2] = mp;
		} else if (_nn[1] <= mm && _n[1] < mm) {
			_q[2] = qMinus(mm, _n[1], _n[2], _n[3], _q[1], _q[2], _q[3]);
			_n[2] = mm;
		}

		mm = _n[3] - 1.0;
		mp = _n[3] + 1.0;
		if (_nn[2] >= mp && _n[4] > mp) {
			_q[3] = qPlus(mp, _n[2], _n[3], _n[4], _q[2], _q[3], _q[4]);
			_n[3] = mp;
		} else if (_nn[2] <= mm && _n[2] < mm) {
			_q[3] = qMinus(mm, _n[2], _n[3], _n[4], _q[2], _q[3], _q[4]);
			_n[3] = mm;
		}
	}
Combine two {@code Quantile} objects.

@since 3.1

@param other the other {@code Quantile} object to combine
@return {@code this}
@throws java.lang.NullPointerException if the {@code other} object is
        {@code null}.
@throws java.lang.IllegalArgumentException if the {@link #quantile}
        of the {@code other} object differs from {@code this} one.
jenetics/src/main/java/io/jenetics/stat/Quantile.java