Erf(z) should return 1.0 for z 'large' but fails with a
MaxIterationsExceededException for z > 26.0.
-----------------------------------------------------------------------------------------------------
Key: MATH-301
URL: https://issues.apache.org/jira/browse/MATH-301
Project: Commons Math
Issue Type: Bug
Affects Versions: 2.0
Environment: MacOS and Linux
Reporter: Tom Milac
Erf(z) should return 1.0 for z 'large' but fails with a
MaxIterationsExceededException for z > 26.0.
Sample code
-----------------
import org.apache.commons.math.MathException;
import org.apache.commons.math.special.Erf;
public class TestErf {
public TestErf() {
}
public static void main(String[] args) {
double z = Double.NEGATIVE_INFINITY;
try {
for(int i=0; i<100; i++) {
z = i;
System.out.println("z = " + z + " erf(z) = " + Erf.erf(z));
}
System.out.flush();
} catch (MathException mex) {
System.out.println("z failed = " + z);
mex.printStackTrace();
}
}
}
Output
---------
z = 0.0 erf(z) = 0.0
z = 1.0 erf(z) = 0.842700792949715
z = 2.0 erf(z) = 0.9953222650189528
z = 3.0 erf(z) = 0.9999779095030024
z = 4.0 erf(z) = 0.9999999845827416
z = 5.0 erf(z) = 0.9999999999984622
z = 6.0 erf(z) = 0.9999999999999997
z = 7.0 erf(z) = 1.000000000000001
z = 8.0 erf(z) = 0.9999999999999986
z = 9.0 erf(z) = 1.000000000000003
z = 10.0 erf(z) = 1.0000000000000115
z = 11.0 erf(z) = 1.0000000000000016
z = 12.0 erf(z) = 0.9999999999999941
z = 13.0 erf(z) = 0.9999999999999846
z = 14.0 erf(z) = 1.0000000000000024
z = 15.0 erf(z) = 0.9999999999999805
z = 16.0 erf(z) = 0.9999999999999988
z = 17.0 erf(z) = 0.9999999999999949
z = 18.0 erf(z) = 0.9999999999999907
z = 19.0 erf(z) = 0.9999999999999731
z = 20.0 erf(z) = 0.9999999999999862
z = 21.0 erf(z) = 0.9999999999999721
z = 22.0 erf(z) = 1.000000000000017
z = 23.0 erf(z) = 1.0000000000000577
z = 24.0 erf(z) = 1.000000000000054
z = 25.0 erf(z) = 1.0000000000000262
z = 26.0 erf(z) = 1.0000000000000735
z failed = 27.0
org.apache.commons.math.MaxIterationsExceededException: Maximal number of
iterations (10,000) exceeded
at
org.apache.commons.math.special.Gamma.regularizedGammaP(Gamma.java:181)
at org.apache.commons.math.special.Erf.erf(Erf.java:51)
at org.fhcrc.math.minimization.TestErf.main(TestErf.java:23)
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
