tools/footprint/linear-regression.awk

   1 # ***** BEGIN LICENSE BLOCK *****
   2 # Version: MPL 1.1/GPL 2.0/LGPL 2.1
   3 #
   4 # The contents of this file are subject to the Mozilla Public License Version
   5 # 1.1 (the "License"); you may not use this file except in compliance with
   6 # the License. You may obtain a copy of the License at
   7 # http://www.mozilla.org/MPL/
   8 #
   9 # Software distributed under the License is distributed on an "AS IS" basis,
  10 # WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  11 # for the specific language governing rights and limitations under the
  12 # License.
  13 #
  14 # The Original Code is linear-regression.awk, released
  15 # November 13, 2000.
  16 #
  17 # The Initial Developer of the Original Code is
  18 # Netscape Communications Corporation.
  19 # Portions created by the Initial Developer are Copyright (C) 2000
  20 # the Initial Developer. All Rights Reserved.
  21 #
  22 # Contributor(s):
  23 #   Chris Waterson <waterson@netscape.com>
  24 #
  25 # Alternatively, the contents of this file may be used under the terms of
  26 # either the GNU General Public License Version 2 or later (the "GPL"), or
  27 # the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28 # in which case the provisions of the GPL or the LGPL are applicable instead
  29 # of those above. If you wish to allow use of your version of this file only
  30 # under the terms of either the GPL or the LGPL, and not to allow others to
  31 # use your version of this file under the terms of the MPL, indicate your
  32 # decision by deleting the provisions above and replace them with the notice
  33 # and other provisions required by the GPL or the LGPL. If you do not delete
  34 # the provisions above, a recipient may use your version of this file under
  35 # the terms of any one of the MPL, the GPL or the LGPL.
  36 #
  37 # ***** END LICENSE BLOCK *****
  38
  39 function regress(DATAPOINTS,SX,SY,SXY,SX2)
  40 {
  41    b1 = (DATAPOINTS * SXY - SX * SY) / (DATAPOINTS * SX2 - SX * SX);
  42    b0 = (SY - b1 * SX ) / DATAPOINTS;
  43    return b1 " * x + " b0;
  44 }
  45
  46 BEGIN {
  47         if (!Skip) Skip = 0;
  48         if (Interval)
  49         {
  50            Count = 0;
  51            IntervalCount = 0;
  52         }
  53       }
  54
  55 NR>Skip {
  56         sx += $1;
  57         sy += $2;
  58         sxy += $1 * $2;
  59         sx2 += $1 * $1;
  60         #print NR " " sx " " sy " " sxy " " sx2
  61
  62         if (Interval)
  63         {
  64            if(Count == Interval-1)
  65            {
  66               IntervalCount += 1;
  67
  68               print NR-Count, "-", NR, ":  ", regress(Count,isx,isy,isxy,isx2);
  69
  70               Count = 0;
  71               isx = 0;
  72               isy = 0;
  73               isxy = 0;
  74               isx2 = 0;
  75            }
  76            else
  77            {
  78               Count += 1;
  79               isx += $1;
  80               isy += $2;
  81               isxy += $1 * $2;
  82               isx2 += $1 * $1;
  83            }
  84         }
  85      }
  86
  87 END {
  88        if(Interval) {
  89           print NR-Count, "-", NR, ":  ", regress(Count,isx,isy,isxy,isx2);
  90        }
  91        print regress(NR-Skip, sx, sy, sxy, sx2);
  92     }