Return-Path: X-Original-To: apmail-commons-issues-archive@minotaur.apache.org Delivered-To: apmail-commons-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 7D0CB1885E for ; Sat, 23 Apr 2016 01:08:13 +0000 (UTC) Received: (qmail 88135 invoked by uid 500); 23 Apr 2016 01:08:13 -0000 Delivered-To: apmail-commons-issues-archive@commons.apache.org Received: (qmail 88054 invoked by uid 500); 23 Apr 2016 01:08:13 -0000 Mailing-List: contact issues-help@commons.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: issues@commons.apache.org Delivered-To: mailing list issues@commons.apache.org Received: (qmail 88035 invoked by uid 99); 23 Apr 2016 01:08:13 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Sat, 23 Apr 2016 01:08:13 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id ED83B2C1F5A for ; Sat, 23 Apr 2016 01:08:12 +0000 (UTC) Date: Sat, 23 Apr 2016 01:08:12 +0000 (UTC) From: "Gilles (JIRA)" To: issues@commons.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (MATH-1318) Implement reflection formula to digamma function to improve performance on negative values. MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/MATH-1318?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15254993#comment-15254993 ] Gilles commented on MATH-1318: ------------------------------ Hi Eric. Sorry that your request seems to have been ignored. Hopefully you are still around. Could you please check out the "develop" branch and issue a new pull request? Thanks in advance. > Implement reflection formula to digamma function to improve performance on negative values. > ------------------------------------------------------------------------------------------- > > Key: MATH-1318 > URL: https://issues.apache.org/jira/browse/MATH-1318 > Project: Commons Math > Issue Type: Improvement > Reporter: Eric Prescott-Gagnon > Priority: Minor > > The performance of the digamma( x ) function is in O(|x|) for negative values. Implementing the reflection formula (https://en.wikipedia.org/wiki/Digamma_function#Reflection_formula) can improve the performance in that case. > github pull request: https://github.com/apache/commons-math/pull/23 -- This message was sent by Atlassian JIRA (v6.3.4#6332)