private void floor0() {
		// value = unscaled * 2^(scale-fracbits)
		if (scale < 0) {
			makeZero();
			return;
		}
		int nbitsUnderOne = fracbits - scale - 1;
		unscaled = unscaled.shiftRight(nbitsUnderOne).shiftLeft(nbitsUnderOne);
	}
{@code this=sqrt(this)}

	<p>Square root by abacus algorithm, Martin Guy @ UKC, June 1985.
	From a book on programming abaci by Mr C. Woo.
	Argument is a positive integer, as is result.

 <p>adapted from http://medialab.freaknet.org/martin/src/sqrt/sqrt.c
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/pcode/floatformat/BigFloat.java