Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id BF0F020049D for ; Wed, 9 Aug 2017 22:42:04 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id BD7D416A106; Wed, 9 Aug 2017 20:42:04 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 111C816A105 for ; Wed, 9 Aug 2017 22:42:03 +0200 (CEST) Received: (qmail 60765 invoked by uid 500); 9 Aug 2017 20:42:03 -0000 Mailing-List: contact issues-help@systemml.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@systemml.apache.org Delivered-To: mailing list issues@systemml.apache.org Received: (qmail 60756 invoked by uid 99); 9 Aug 2017 20:42:03 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd3-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 09 Aug 2017 20:42:03 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd3-us-west.apache.org (ASF Mail Server at spamd3-us-west.apache.org) with ESMTP id D31D81807DC for ; Wed, 9 Aug 2017 20:42:02 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd3-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: -100.002 X-Spam-Level: X-Spam-Status: No, score=-100.002 tagged_above=-999 required=6.31 tests=[RP_MATCHES_RCVD=-0.001, SPF_PASS=-0.001, USER_IN_WHITELIST=-100] autolearn=disabled Received: from mx1-lw-us.apache.org ([10.40.0.8]) by localhost (spamd3-us-west.apache.org [10.40.0.10]) (amavisd-new, port 10024) with ESMTP id O1VpxvOcrKFa for ; Wed, 9 Aug 2017 20:42:02 +0000 (UTC) Received: from mailrelay1-us-west.apache.org (mailrelay1-us-west.apache.org [209.188.14.139]) by mx1-lw-us.apache.org (ASF Mail Server at mx1-lw-us.apache.org) with ESMTP id 6EDEF60DCF for ; Wed, 9 Aug 2017 20:42:01 +0000 (UTC) Received: from jira-lw-us.apache.org (unknown [207.244.88.139]) by mailrelay1-us-west.apache.org (ASF Mail Server at mailrelay1-us-west.apache.org) with ESMTP id E66F2E0DFE for ; Wed, 9 Aug 2017 20:42:00 +0000 (UTC) Received: from jira-lw-us.apache.org (localhost [127.0.0.1]) by jira-lw-us.apache.org (ASF Mail Server at jira-lw-us.apache.org) with ESMTP id 66FFC2416D for ; Wed, 9 Aug 2017 20:42:00 +0000 (UTC) Date: Wed, 9 Aug 2017 20:42:00 +0000 (UTC) From: "Matthias Boehm (JIRA)" To: issues@systemml.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Resolved] (SYSTEMML-1761) Sparsity-exploiting weighted squared loss w/o weights MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 archived-at: Wed, 09 Aug 2017 20:42:04 -0000 [ https://issues.apache.org/jira/browse/SYSTEMML-1761?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Matthias Boehm resolved SYSTEMML-1761. -------------------------------------- Resolution: Fixed Assignee: Matthias Boehm Fix Version/s: SystemML 1.0 > Sparsity-exploiting weighted squared loss w/o weights > ----------------------------------------------------- > > Key: SYSTEMML-1761 > URL: https://issues.apache.org/jira/browse/SYSTEMML-1761 > Project: SystemML > Issue Type: Task > Reporter: Matthias Boehm > Assignee: Matthias Boehm > Fix For: SystemML 1.0 > > > There are existing rewrites and fused operators for weighted squared loss (wsloss). However, for the wsloss type {{NONE}}, i.e., without weights {{sum((X-(U%*%t(V)))^2)}}, the implementation is not sparsity-exploiting leading to huge (unnecessary) computation overhead for the outer-product-like multiply of factors. As it turns out, this expression can be rewritten into a sparsity-exploiting form as follows: > {code} > sum ((X - U %*% t(V)) ^ 2) > -> sum(X^2) - sum(2 * (X * (U%*%t(V)))) + sum((U%*%t(V))^2) > -> sum(X^2) - sum(2 * (X * (U%*%t(V)))) + sum ((t(U) %*% U) * (t(V) %*% V)) > {code} > This task aims to change the block-level wsloss NONE implementation to exploit this logical rewrite by computing {{sum(X^2) - sum(2 * (X * (U%*%t(V))))}} in a sparsity-exploiting pass over non-zeros in X and a subsequent correction for {{+ sum ((t(U) %*% U) * (t(V) %*% V))}} via two tsmm operations. -- This message was sent by Atlassian JIRA (v6.4.14#64029)