lib/MECON/Graph/external/jpgraph/src/jpgraph_log.php

   1 <?php
   2 /*=======================================================================
   3 // File:        JPGRAPH_LOG.PHP
   4 // Description: Log scale plot extension for JpGraph
   5 // Created:     2001-01-08
   6 // Author:      Johan Persson (johanp@aditus.nu)
   7 // Ver:         $Id: jpgraph_log.php,v 1.15.2.1 2003/08/15 15:27:40 aditus Exp $
   8 //
   9 // License:     This code is released under QPL
  10 // Copyright (C) 2001,2002 Johan Persson
  11 //========================================================================
  12 */
  13
  14
  15 DEFINE('LOGLABELS_PLAIN',0);
  16 DEFINE('LOGLABELS_MAGNITUDE',1);
  17
  18 //===================================================
  19 // CLASS LogScale
  20 // Description: Logarithmic scale between world and screen
  21 //===================================================
  22 class LogScale extends LinearScale {
  23 //---------------
  24 // CONSTRUCTOR
  25
  26     // Log scale is specified using the log of min and max
  27     function LogScale($min,$max,$type="y") {
  28         $this->LinearScale($min,$max,$type);
  29         $this->ticks = new LogTicks();
  30         $this->name = 'log';
  31     }
  32
  33 //----------------
  34 // PUBLIC METHODS
  35
  36     // Translate between world and screen
  37     function    Translate($a) {
  38         if( $a < 0 ) {
  39             JpGraphError::Raise("Negative data values can not be used in a log scale.");
  40             exit(1);
  41         }
  42         if( $a==0 ) $a=1;
  43         $a=log10($a);
  44         return ceil($this->off + ($a*1.0 - $this->scale[0]) * $this->scale_factor);
  45     }
  46
  47     // Relative translate (don't include offset) usefull when we just want
  48     // to know the relative position (in pixels) on the axis
  49     function RelTranslate($a) {
  50         if( $a==0 ) $a=1;
  51         $a=log10($a);
  52         return round(($a*1.0 - $this->scale[0]) * $this->scale_factor);
  53     }
  54
  55     // Use bcpow() for increased precision
  56     function GetMinVal() {
  57         if( function_exists("bcpow") )
  58             return round(bcpow(10,$this->scale[0],15),14);
  59         else
  60             return round(pow(10,$this->scale[0]));
  61     }
  62
  63     function GetMaxVal() {
  64         if( function_exists("bcpow") )
  65             return round(bcpow(10,$this->scale[1],15),14);
  66         else
  67             return round(pow(10,$this->scale[1]));
  68     }
  69
  70     // Logarithmic autoscaling is much simplier since we just
  71     // set the min and max to logs of the min and max values.
  72     // Note that for log autoscale the "maxstep" the fourth argument
  73     // isn't used. This is just included to give the method the same
  74     // signature as the linear counterpart.
  75     function AutoScale(&$img,$min,$max,$dummy) {
  76         if( $min==0 ) $min=1;
  77         assert($max>0);
  78         $smin = floor(log10($min));
  79         $smax = ceil(log10($max));
  80         $this->Update($img,$smin,$smax);
  81     }
  82 //---------------
  83 // PRIVATE METHODS
  84 } // Class
  85
  86 //===================================================
  87 // CLASS LogTicks
  88 // Description:
  89 //===================================================
  90 class LogTicks extends Ticks{
  91     var $label_logtype=LOGLABELS_MAGNITUDE;
  92 //---------------
  93 // CONSTRUCTOR
  94     function LogTicks() {
  95     }
  96 //---------------
  97 // PUBLIC METHODS
  98     function IsSpecified() {
  99         return true;
 100     }
 101
 102     function SetLabelLogType($aType) {
 103         $this->label_logtype = $aType;
 104     }
 105
 106     // For log scale it's meaningless to speak about a major step
 107     // We just return -1 to make the framework happy (specifically
 108     // StrokeLabels() )
 109     function GetMajor() {
 110         return -1;
 111     }
 112
 113     function SetTextLabelStart($aStart) {
 114         JpGraphError::Raise('Specifying tick interval for a logarithmic scale is undefined. Remove any calls to SetTextLabelStart() or SetTextTickInterval() on the logarithmic scale.');
 115     }
 116
 117     function SetXLabelOffset($dummy) {
 118         // For log scales we dont care about XLabel offset
 119     }
 120
 121     // Draw ticks on image "img" using scale "scale". The axis absolute
 122     // position in the image is specified in pos, i.e. for an x-axis
 123     // it specifies the absolute y-coord and for Y-ticks it specified the
 124     // absolute x-position.
 125     function Stroke(&$img,&$scale,$pos) {
 126         $start = $scale->GetMinVal();
 127         $limit = $scale->GetMaxVal();
 128         $nextMajor = 10*$start;
 129         $step = $nextMajor / 10.0;
 130
 131
 132         $img->SetLineWeight($this->weight);
 133
 134         if( $scale->type == "y" ) {
 135             // member direction specified if the ticks should be on
 136             // left or right side.
 137             $a=$pos + $this->direction*$this->GetMinTickAbsSize();
 138             $a2=$pos + $this->direction*$this->GetMajTickAbsSize();
 139
 140             $count=1;
 141             $this->maj_ticks_pos[0]=$scale->Translate($start);
 142             $this->maj_ticklabels_pos[0]=$scale->Translate($start);
 143             if( $this->supress_first )
 144                 $this->maj_ticks_label[0]="";
 145             else {
 146                 if( $this->label_formfunc != '' ) {
 147                     $f = $this->label_formfunc;
 148                     $this->maj_ticks_label[0]=call_user_func($f,$start);
 149                 }
 150                 elseif( $this->label_logtype == LOGLABELS_PLAIN )
 151                     $this->maj_ticks_label[0]=$start;
 152                 else
 153                     $this->maj_ticks_label[0]='10^'.round(log10($start));
 154             }
 155             $i=1;
 156             for($y=$start; $y<=$limit; $y+=$step,++$count  ) {
 157                 $ys=$scale->Translate($y);
 158                 $this->ticks_pos[]=$ys;
 159                 $this->ticklabels_pos[]=$ys;
 160                 if( $count % 10 == 0 ) {
 161                     if( $this->majcolor!="" ) {
 162                         $img->PushColor($this->majcolor);
 163                         $img->Line($pos,$ys,$a2,$ys);
 164                         $img->PopColor();
 165                     }
 166                     else
 167                         $img->Line($pos,$ys,$a2,$ys);
 168
 169                     $this->maj_ticks_pos[$i]=$ys;
 170                     $this->maj_ticklabels_pos[$i]=$ys;
 171
 172                     if( $this->label_formfunc != '' ) {
 173                         $f = $this->label_formfunc;
 174                         $this->maj_ticks_label[$i]=call_user_func($f,$nextMajor);
 175                     }
 176                     elseif( $this->label_logtype == 0 )
 177                         $this->maj_ticks_label[$i]=$nextMajor;
 178                     else
 179                         $this->maj_ticks_label[$i]='10^'.round(log10($nextMajor));
 180                     ++$i;
 181                     $nextMajor *= 10;
 182                     $step *= 10;
 183                     $count=1;
 184                 }
 185                 else {
 186                     if( $this->mincolor!="" ) $img->PushColor($this->mincolor);
 187                     $img->Line($pos,$ys,$a,$ys);
 188                     if( $this->mincolor!="" ) $img->PopCOlor();
 189                 }
 190             }
 191         }
 192         else {
 193             $a=$pos - $this->direction*$this->GetMinTickAbsSize();
 194             $a2=$pos - $this->direction*$this->GetMajTickAbsSize();
 195             $count=1;
 196             $this->maj_ticks_pos[0]=$scale->Translate($start);
 197             $this->maj_ticklabels_pos[0]=$scale->Translate($start);
 198             if( $this->supress_first )
 199                 $this->maj_ticks_label[0]="";
 200             else {
 201                 if( $this->label_formfunc != '' ) {
 202                     $f = $this->label_formfunc;
 203                     $this->maj_ticks_label[0]=call_user_func($f,$start);
 204                 }
 205                 elseif( $this->label_logtype == 0 )
 206                     $this->maj_ticks_label[0]=$start;
 207                 else
 208                     $this->maj_ticks_label[0]='10^'.round(log10($start));
 209             }
 210             $i=1;
 211             for($x=$start; $x<=$limit; $x+=$step,++$count  ) {
 212                 $xs=$scale->Translate($x);
 213                 $this->ticks_pos[]=$xs;
 214                 $this->ticklabels_pos[]=$xs;
 215                 if( $count % 10 == 0 ) {
 216                     $img->Line($xs,$pos,$xs,$a2);
 217                     $this->maj_ticks_pos[$i]=$xs;
 218                     $this->maj_ticklabels_pos[$i]=$xs;
 219
 220                     if( $this->label_formfunc != '' ) {
 221                         $f = $this->label_formfunc;
 222                         $this->maj_ticks_label[$i]=call_user_func($f,$nextMajor);
 223                     }
 224                     elseif( $this->label_logtype == 0 )
 225                         $this->maj_ticks_label[$i]=$nextMajor;
 226                     else
 227                         $this->maj_ticks_label[$i]='10^'.round(log10($nextMajor));
 228                     ++$i;
 229                     $nextMajor *= 10;
 230                     $step *= 10;
 231                     $count=1;
 232                 }
 233                 else
 234                     $img->Line($xs,$pos,$xs,$a);
 235             }
 236         }
 237         return true;
 238     }
 239 } // Class
 240 /* EOF */
 241 ?>