forked from bartvdbraak/blender
149 lines
2.6 KiB
C++
149 lines
2.6 KiB
C++
/**
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* $Id$
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*/
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/*
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*
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* Template Numerical Toolkit (TNT): Linear Algebra Module
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*
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* Mathematical and Computational Sciences Division
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* National Institute of Technology,
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* Gaithersburg, MD USA
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*
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*
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* This software was developed at the National Institute of Standards and
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* Technology (NIST) by employees of the Federal Government in the course
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* of their official duties. Pursuant to title 17 Section 105 of the
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* United States Code, this software is not subject to copyright protection
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* and is in the public domain. The Template Numerical Toolkit (TNT) is
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* an experimental system. NIST assumes no responsibility whatsoever for
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* its use by other parties, and makes no guarantees, expressed or implied,
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* about its quality, reliability, or any other characteristic.
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*
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* BETA VERSION INCOMPLETE AND SUBJECT TO CHANGE
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* see http://math.nist.gov/tnt for latest updates.
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*
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*/
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// Header file for scalar math functions
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#ifndef TNTMATH_H
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#define TNTMATH_H
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// conventional functions required by several matrix algorithms
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namespace TNT
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{
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struct TNTException {
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int i;
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};
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inline double abs(double t)
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{
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return ( t > 0 ? t : -t);
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}
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inline double min(double a, double b)
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{
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return (a < b ? a : b);
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}
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inline double max(double a, double b)
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{
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return (a > b ? a : b);
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}
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inline float abs(float t)
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{
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return ( t > 0 ? t : -t);
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}
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inline float min(float a, float b)
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{
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return (a < b ? a : b);
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}
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inline int min(int a,int b) {
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return (a < b ? a : b);
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}
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inline float max(float a, float b)
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{
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return (a > b ? a : b);
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}
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inline double sign(double a)
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{
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return (a > 0 ? 1.0 : -1.0);
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}
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inline double sign(double a,double b) {
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return (b >= 0.0 ? TNT::abs(a) : -TNT::abs(a));
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}
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inline float sign(float a,float b) {
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return (b >= 0.0f ? TNT::abs(a) : -TNT::abs(a));
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}
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inline float sign(float a)
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{
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return (a > 0.0 ? 1.0f : -1.0f);
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}
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inline float pythag(float a, float b)
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{
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float absa,absb;
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absa = abs(a);
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absb = abs(b);
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if (absa > absb) {
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float sqr = absb/absa;
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sqr *= sqr;
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return absa * float(sqrt(1 + sqr));
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} else {
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if (absb > float(0)) {
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float sqr = absa/absb;
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sqr *= sqr;
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return absb * float(sqrt(1 + sqr));
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} else {
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return float(0);
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}
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}
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}
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inline double pythag(double a, double b)
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{
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double absa,absb;
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absa = abs(a);
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absb = abs(b);
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if (absa > absb) {
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double sqr = absb/absa;
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sqr *= sqr;
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return absa * double(sqrt(1 + sqr));
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} else {
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if (absb > double(0)) {
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double sqr = absa/absb;
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sqr *= sqr;
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return absb * double(sqrt(1 + sqr));
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} else {
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return double(0);
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}
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}
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}
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} /* namespace TNT */
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#endif /* TNTMATH_H */
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