On 20 January 2011 01:16, Mikkel Meyer Andersen <m...@mikl.dk> wrote: > Hi, > > Just a quick question: when a == 0.0f or NA, then a is returned. Why not > just put a special isNA() in the beginning and 0.0f in the existing code?
Because we want to return -0.0 if a == -0.0 and +0.0 if a == +0.0 > Wouldn't it save a tiny bit not loading a? > > Cheers, Mikkel. > Den 19/01/2011 20.26 skrev <s...@apache.org>: >> Author: sebb >> Date: Wed Jan 19 19:26:19 2011 >> New Revision: 1060917 >> >> URL: http://svn.apache.org/viewvc?rev=1060917&view=rev >> Log: >> MATH-478 FastMath is not an exact replacement for StrictMath >> Add signum(float) >> >> Modified: >> > commons/proper/math/branches/MATH_2_X/src/main/java/org/apache/commons/math/util/FastMath.java >> >> Modified: > commons/proper/math/branches/MATH_2_X/src/main/java/org/apache/commons/math/util/FastMath.java >> URL: > http://svn.apache.org/viewvc/commons/proper/math/branches/MATH_2_X/src/main/java/org/apache/commons/math/util/FastMath.java?rev=1060917&r1=1060916&r2=1060917&view=diff >> > ============================================================================== >> --- > commons/proper/math/branches/MATH_2_X/src/main/java/org/apache/commons/math/util/FastMath.java > (original) >> +++ > commons/proper/math/branches/MATH_2_X/src/main/java/org/apache/commons/math/util/FastMath.java > Wed Jan 19 19:26:19 2011 >> @@ -582,6 +582,15 @@ public class FastMath { >> return (a < 0.0) ? -1.0 : ((a > 0.0) ? 1.0 : a); >> } >> >> + /** Compute the signum of a number. >> + * The signum is -1 for negative numbers, +1 for positive numbers and 0 > otherwise >> + * @param a number on which evaluation is done >> + * @return -1, 0, +1 or NaN depending on sign of a >> + */ >> + public static float signum(final float a) { >> + return (a < 0.0f) ? -1.0f : ((a > 0.0f) ? 1.0f : a); >> + } >> + >> /** Compute next number towards positive infinity. >> * @param a number to which neighbor should be computed >> * @return neighbor of a towards positive infinity >> >> > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
