brentworden 2004/06/10 11:34:53
Modified: math/src/java/org/apache/commons/math/special Gamma.java
Log:
removed some condition logic by changing the continued fraction representation.
Revision Changes Path
1.20 +4 -19
jakarta-commons/math/src/java/org/apache/commons/math/special/Gamma.java
Index: Gamma.java
===================================================================
RCS file:
/home/cvs/jakarta-commons/math/src/java/org/apache/commons/math/special/Gamma.java,v
retrieving revision 1.19
retrieving revision 1.20
diff -u -r1.19 -r1.20
--- Gamma.java 7 Jun 2004 20:30:16 -0000 1.19
+++ Gamma.java 10 Jun 2004 18:34:53 -0000 1.20
@@ -236,30 +236,15 @@
// create continued fraction
ContinuedFraction cf = new ContinuedFraction() {
protected double getA(int n, double x) {
- double ret;
- switch(n) {
- case 0: ret = 0.0; break;
- default:
- ret = ((2.0 * n) - 1.0) - a + x; break;
- }
- return ret;
+ return ((2.0 * n) + 1.0) - a + x;
}
protected double getB(int n, double x) {
- double ret;
- double t;
- switch(n) {
- case 1: ret = 1.0; break;
- default:
- t = n - 1.0;
- ret = t * (a - t);
- break;
- }
- return ret;
+ return n * (a - n);
}
};
- ret = cf.evaluate(x, epsilon, maxIterations);
+ ret = 1.0 / cf.evaluate(x, epsilon, maxIterations);
ret = Math.exp(-x + (a * Math.log(x)) - logGamma(a)) * ret;
}
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
