Apache
/
commons-math
mirror of https://github.com/apache/commons-math.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Simplify atan2 expressions when y is non-zero

This commit is contained in:
Alex Herbert 2021-08-18 23:16:01 +01:00
parent 7cb883c54b
commit 56b7b12c2a
1 changed files with 5 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
commons-math-legacy-core/src/main/java/org/apache/commons/math4/legacy/core/jdkmath/AccurateMath.java
View File

@ -2692,16 +2692,14 @@ public final class AccurateMath {
if (invx == 0) { // X is infinite if (invx == 0) { // X is infinite
if (x > 0) { if (x > 0) {
return y; // return +/- 0.0 return y; // return +/- 0.0
} else {
return copySign(Math.PI, y);
} }
return copySign(Math.PI, y);
} }
if (x < 0 || invx < 0) { if (x < 0 || invx < 0) {
return copySign(Math.PI, y); return copySign(Math.PI, y);
} else {
return x * y;
} }
return x * y;
} }
// y cannot now be zero // y cannot now be zero
@ -2731,35 +2729,17 @@ public final class AccurateMath {
} }
if (x == Double.POSITIVE_INFINITY) { if (x == Double.POSITIVE_INFINITY) {
if (y > 0 || 1 / y > 0) { return y > 0 ? 0d : -0d;
return 0d;
}
if (y < 0 || 1 / y < 0) {
return -0d;
}
} }
if (x == Double.NEGATIVE_INFINITY) { if (x == Double.NEGATIVE_INFINITY) {
if (y > 0.0 || 1 / y > 0.0) { return y > 0 ? Math.PI : -Math.PI;
return Math.PI;
}
if (y < 0 || 1 / y < 0) {
return -Math.PI;
}
} }
// Neither y nor x can be infinite or NAN here // Neither y nor x can be infinite or NAN here
if (x == 0) { if (x == 0) {
if (y > 0 || 1 / y > 0) { return y > 0 ? Math.PI * F_1_2 : -Math.PI * F_1_2;
return Math.PI * F_1_2;
}
if (y < 0 || 1 / y < 0) {
return -Math.PI * F_1_2;
}
} }
// Compute ratio r = y/x // Compute ratio r = y/x