Repository: commons-math Updated Branches: refs/heads/master 1f07a0bf7 -> 60bcdd450
Revert "MATH-1441: Cache instance of "TDistribution"." This reverts commit 1f07a0bf70049cb0a2f6b52ea7c261da5adb1abb. Caching does not seem to provide any perfomance improvement. Project: http://git-wip-us.apache.org/repos/asf/commons-math/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-math/commit/60bcdd45 Tree: http://git-wip-us.apache.org/repos/asf/commons-math/tree/60bcdd45 Diff: http://git-wip-us.apache.org/repos/asf/commons-math/diff/60bcdd45 Branch: refs/heads/master Commit: 60bcdd450d6950da981d70b8b08379bdd744c82d Parents: 1f07a0b Author: Gilles <er...@apache.org> Authored: Sat Jan 27 00:39:45 2018 +0100 Committer: Gilles <er...@apache.org> Committed: Sat Jan 27 00:39:45 2018 +0100 ---------------------------------------------------------------------- .../math4/stat/regression/SimpleRegression.java | 26 ++++---------------- 1 file changed, 5 insertions(+), 21 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-math/blob/60bcdd45/src/main/java/org/apache/commons/math4/stat/regression/SimpleRegression.java ---------------------------------------------------------------------- diff --git a/src/main/java/org/apache/commons/math4/stat/regression/SimpleRegression.java b/src/main/java/org/apache/commons/math4/stat/regression/SimpleRegression.java index f7340a3..7fc823d 100644 --- a/src/main/java/org/apache/commons/math4/stat/regression/SimpleRegression.java +++ b/src/main/java/org/apache/commons/math4/stat/regression/SimpleRegression.java @@ -91,9 +91,6 @@ public class SimpleRegression implements Serializable, UpdatingMultipleLinearReg /** include an intercept or not */ private final boolean hasIntercept; - - /** Cache (performance optimization). */ - private transient TDistribution distribution; // ---------------------Public methods-------------------------------------- /** @@ -700,8 +697,9 @@ public class SimpleRegression implements Serializable, UpdatingMultipleLinearReg alpha, 0, 1); } // No advertised NotStrictlyPositiveException here - will return NaN above + TDistribution distribution = new TDistribution(n - 2); return getSlopeStdErr() * - getDistribution().inverseCumulativeProbability(1d - alpha / 2d); + distribution.inverseCumulativeProbability(1d - alpha / 2d); } /** @@ -731,28 +729,14 @@ public class SimpleRegression implements Serializable, UpdatingMultipleLinearReg return Double.NaN; } // No advertised NotStrictlyPositiveException here - will return NaN above - return 2d * (1.0 - getDistribution() - .cumulativeProbability(FastMath.abs(getSlope()) / getSlopeStdErr())); + TDistribution distribution = new TDistribution(n - 2); + return 2d * (1.0 - distribution.cumulativeProbability( + FastMath.abs(getSlope()) / getSlopeStdErr())); } // ---------------------Private methods----------------------------------- /** - * Computes or return a cached distribution. - * - * @return the distribution. - */ - private TDistribution getDistribution() { - final double numDeg = n - 2; - if (distribution == null || - distribution.getDegreesOfFreedom() != numDeg) { - distribution = new TDistribution(numDeg); - } - - return distribution; - } - - /** * Returns the intercept of the estimated regression line, given the slope. * <p> * Will return <code>NaN</code> if slope is <code>NaN</code>.</p>
