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new 32dbe34 Remove overflow protection to compute average.
32dbe34 is described below
commit 32dbe346e717ffafa188b0b1d9cf51006b852c17
Author: Alex Herbert <[email protected]>
AuthorDate: Mon Dec 9 00:37:13 2019 +0000
Remove overflow protection to compute average.
The sqrt() switches to using polar coordinates to compute the result.
---
.../apache/commons/numbers/complex/Complex.java | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git
a/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
b/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
index 873db5f..4a4ee76 100644
---
a/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
+++
b/commons-numbers-complex/src/main/java/org/apache/commons/numbers/complex/Complex.java
@@ -1701,6 +1701,13 @@ public final class Complex implements Serializable {
* @return the square root of the complex number.
*/
private static Complex sqrt(double real, double imaginary) {
+// final double abs = getAbsolute(real, imaginary);
+// final double sqrtAbs = Math.sqrt(abs);
+// final double halfArg = getArgument(real, imaginary) / 2;
+// final double re = sqrtAbs * Math.cos(halfArg);
+// final double im = sqrtAbs * Math.sin(halfArg);
+// return new Complex(re, im);
+
// Special case for infinite imaginary for all real including nan
if (Double.isInfinite(imaginary)) {
return new Complex(Double.POSITIVE_INFINITY, imaginary);
@@ -1712,7 +1719,7 @@ public final class Complex implements Serializable {
return new Complex(0, imaginary);
}
final double abs = getAbsolute(real, imaginary);
- final double av = average(Math.abs(real), abs);
+ final double av = (Math.abs(real) + abs) / 2;
if (av == Double.POSITIVE_INFINITY) {
// Compute in polar coords.
// This handles extreme values that fail in the cartesian
representation.
@@ -1747,19 +1754,6 @@ public final class Complex implements Serializable {
}
/**
- * Compute {@code (a + b) / 2} without overflow.
- *
- * @param a the a
- * @param b the b
- * @return the average
- */
- private static double average(double a, double b) {
- return (a < b) ?
- a + (b - a) / 2 :
- b + (a - b) / 2;
- }
-
- /**
* Compute the
* <a href="http://mathworld.wolfram.com/Tangent.html";>
* tangent</a> of this complex number.
