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site/jpgraph/jpgraph_line.php 23.2 KB
8ec98c9f   Guillaume   MAJ
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  <?php
  /*=======================================================================
   // File:  		 JPGRAPH_LINE.PHP
   // Description: Line plot extension for JpGraph
   // Created:  	 2001-01-08
   // Ver:  		 $Id: jpgraph_line.php 1921 2009-12-11 11:46:39Z ljp $
   //
   // Copyright (c) Asial Corporation. All rights reserved.
   //========================================================================
   */
  
  require_once ('jpgraph_plotmark.inc.php');
  
  // constants for the (filled) area
  DEFINE("LP_AREA_FILLED", true);
  DEFINE("LP_AREA_NOT_FILLED", false);
  DEFINE("LP_AREA_BORDER",false);
  DEFINE("LP_AREA_NO_BORDER",true);
  
  //===================================================
  // CLASS LinePlot
  // Description:
  //===================================================
  class LinePlot extends Plot{
      public $mark=null;
      protected $filled=false;
      protected $fill_color='blue';
      protected $step_style=false, $center=false;
      protected $line_style=1; // Default to solid
      protected $filledAreas = array(); // array of arrays(with min,max,col,filled in them)
      public $barcenter=false;  // When we mix line and bar. Should we center the line in the bar.
      protected $fillFromMin = false, $fillFromMax = false;
      protected $fillgrad=false,$fillgrad_fromcolor='navy',$fillgrad_tocolor='silver',$fillgrad_numcolors=100;
      protected $iFastStroke=false;
  
      //---------------
      // CONSTRUCTOR
      function __construct($datay,$datax=false) {
          parent::__construct($datay,$datax);
          $this->mark = new PlotMark() ;
          $this->color = ColorFactory::getColor();
          $this->fill_color = $this->color;
      }
      //---------------
      // PUBLIC METHODS
  
      function SetFilled($aFlg=true) {
  		$this->filled = $aFlg;
      }
  
      function SetBarCenter($aFlag=true) {
          $this->barcenter=$aFlag;
      }
  
      function SetStyle($aStyle) {
          $this->line_style=$aStyle;
      }
  
      function SetStepStyle($aFlag=true) {
          $this->step_style = $aFlag;
      }
  
      function SetColor($aColor) {
          parent::SetColor($aColor);
      }
  
      function SetFillFromYMin($f=true) {
          $this->fillFromMin = $f ;
      }
  
      function SetFillFromYMax($f=true) {
          $this->fillFromMax = $f ;
      }
  
      function SetFillColor($aColor,$aFilled=true) {
      	//$this->color = $aColor;
          $this->fill_color=$aColor;
          $this->filled=$aFilled;
      }
  
      function SetFillGradient($aFromColor,$aToColor,$aNumColors=100,$aFilled=true) {
          $this->fillgrad_fromcolor = $aFromColor;
          $this->fillgrad_tocolor   = $aToColor;
          $this->fillgrad_numcolors = $aNumColors;
          $this->filled = $aFilled;
          $this->fillgrad = true;
      }
  
      function Legend($graph) {
          if( $this->legend!="" ) {
              if( $this->filled && !$this->fillgrad ) {
                  $graph->legend->Add($this->legend,
                  $this->fill_color,$this->mark,0,
                  $this->legendcsimtarget,$this->legendcsimalt,$this->legendcsimwintarget);
              }
              elseif( $this->fillgrad ) {
                  $color=array($this->fillgrad_fromcolor,$this->fillgrad_tocolor);
                  // In order to differentiate between gradients and cooors specified as an RGB triple
                  $graph->legend->Add($this->legend,$color,"",-2 /* -GRAD_HOR */,
                  $this->legendcsimtarget,$this->legendcsimalt,$this->legendcsimwintarget);
              } else {
                  $graph->legend->Add($this->legend,
                  $this->color,$this->mark,$this->line_style,
                  $this->legendcsimtarget,$this->legendcsimalt,$this->legendcsimwintarget);
              }
          }
      }
  
      function AddArea($aMin=0,$aMax=0,$aFilled=LP_AREA_NOT_FILLED,$aColor="gray9",$aBorder=LP_AREA_BORDER) {
          if($aMin > $aMax) {
              // swap
              $tmp = $aMin;
              $aMin = $aMax;
              $aMax = $tmp;
          }
          $this->filledAreas[] = array($aMin,$aMax,$aColor,$aFilled,$aBorder);
      }
  
      // Gets called before any axis are stroked
      function PreStrokeAdjust($graph) {
  
          // If another plot type have already adjusted the
          // offset we don't touch it.
          // (We check for empty in case the scale is  a log scale
          // and hence doesn't contain any xlabel_offset)
          if( empty($graph->xaxis->scale->ticks->xlabel_offset) || $graph->xaxis->scale->ticks->xlabel_offset == 0 ) {
              if( $this->center ) {
                  ++$this->numpoints;
                  $a=0.5; $b=0.5;
              } else {
                  $a=0; $b=0;
              }
              $graph->xaxis->scale->ticks->SetXLabelOffset($a);
              $graph->SetTextScaleOff($b);
              //$graph->xaxis->scale->ticks->SupressMinorTickMarks();
          }
      }
  
      function SetFastStroke($aFlg=true) {
          $this->iFastStroke = $aFlg;
      }
  
      function FastStroke($img,$xscale,$yscale,$aStartPoint=0,$exist_x=true) {
          // An optimized stroke for many data points with no extra
          // features but 60% faster. You can't have values or line styles, or null
          // values in plots.
          $numpoints=count($this->coords[0]);
          if( $this->barcenter ) {
              $textadj = 0.5-$xscale->text_scale_off;
          }
          else {
              $textadj = 0;
          }
  
          $img->SetColor($this->color);
          $img->SetLineWeight($this->weight);
          $pnts=$aStartPoint;
          while( $pnts < $numpoints ) {
              if( $exist_x ) {
                  $x=$this->coords[1][$pnts];
              }
              else {
                  $x=$pnts+$textadj;
              }
              $xt = $xscale->Translate($x);
              $y=$this->coords[0][$pnts];
              $yt = $yscale->Translate($y);
              if( is_numeric($y) ) {
                  $cord[] = $xt;
                  $cord[] = $yt;
              }
              elseif( $y == '-' && $pnts > 0 ) {
                  // Just ignore
              }
              else {
                  JpGraphError::RaiseL(10002);//('Plot too complicated for fast line Stroke. Use standard Stroke()');
              }
              ++$pnts;
          } // WHILE
  
          $img->Polygon($cord,false,true);
      }
  
      function Stroke($img,$xscale,$yscale) {
          $idx=0;
          $numpoints=count($this->coords[0]);
          if( isset($this->coords[1]) ) {
              if( count($this->coords[1])!=$numpoints ) {
                  JpGraphError::RaiseL(2003,count($this->coords[1]),$numpoints);
              //("Number of X and Y points are not equal. Number of X-points:".count($this->coords[1])." Number of Y-points:$numpoints");
              }
              else {
                  $exist_x = true;
              }
          }
          else {
              $exist_x = false;
          }
  
          if( $this->barcenter ) {
              $textadj = 0.5-$xscale->text_scale_off;
          }
          else {
              $textadj = 0;
          }
  
          // Find the first numeric data point
          $startpoint=0;
          while( $startpoint < $numpoints && !is_numeric($this->coords[0][$startpoint]) ) {
              ++$startpoint;
          }
  
          // Bail out if no data points
          if( $startpoint == $numpoints ) return;
  
          if( $this->iFastStroke ) {
              $this->FastStroke($img,$xscale,$yscale,$startpoint,$exist_x);
              return;
          }
  
          if( $exist_x ) {
              $xs=$this->coords[1][$startpoint];
          }
          else {
              $xs= $textadj+$startpoint;
          }
  
          $img->SetStartPoint($xscale->Translate($xs),
          $yscale->Translate($this->coords[0][$startpoint]));
  
          if( $this->filled ) {
              if( $this->fillFromMax ) {
                  //$max = $yscale->GetMaxVal();
                  $cord[$idx++] = $xscale->Translate($xs);
                  $cord[$idx++] = $yscale->scale_abs[1];
              }
              else {
                  $min = $yscale->GetMinVal();
                  if( $min > 0 || $this->fillFromMin ) {
                      $fillmin = $yscale->scale_abs[0];//Translate($min);
                  }
                  else {
                      $fillmin = $yscale->Translate(0);
                  }
  
                  $cord[$idx++] = $xscale->Translate($xs);
                  $cord[$idx++] = $fillmin;
              }
          }
          $xt = $xscale->Translate($xs);
          $yt = $yscale->Translate($this->coords[0][$startpoint]);
          $cord[$idx++] = $xt;
          $cord[$idx++] = $yt;
          $yt_old = $yt;
          $xt_old = $xt;
          $y_old = $this->coords[0][$startpoint];
  
          $this->value->Stroke($img,$this->coords[0][$startpoint],$xt,$yt);
  
          $img->SetColor($this->color);
          $img->SetLineWeight($this->weight);
          $img->SetLineStyle($this->line_style);
          $pnts=$startpoint+1;
          $firstnonumeric = false;
  
  
          while( $pnts < $numpoints ) {
  
              if( $exist_x ) {
                  $x=$this->coords[1][$pnts];
              }
              else {
                  $x=$pnts+$textadj;
              }
              $xt = $xscale->Translate($x);
              $yt = $yscale->Translate($this->coords[0][$pnts]);
  
              $y=$this->coords[0][$pnts];
              if( $this->step_style ) {
                  // To handle null values within step style we need to record the
                  // first non numeric value so we know from where to start if the
                  // non value is '-'.
                  if( is_numeric($y) ) {
                      $firstnonumeric = false;
                      if( is_numeric($y_old) ) {
                          $img->StyleLine($xt_old,$yt_old,$xt,$yt_old);
                          $img->StyleLine($xt,$yt_old,$xt,$yt);
                      }
                      elseif( $y_old == '-' ) {
                          $img->StyleLine($xt_first,$yt_first,$xt,$yt_first);
                          $img->StyleLine($xt,$yt_first,$xt,$yt);
                      }
                      else {
                          $yt_old = $yt;
                          $xt_old = $xt;
                      }
                      $cord[$idx++] = $xt;
                      $cord[$idx++] = $yt_old;
                      $cord[$idx++] = $xt;
                      $cord[$idx++] = $yt;
                  }
                  elseif( $firstnonumeric==false ) {
                      $firstnonumeric = true;
                      $yt_first = $yt_old;
                      $xt_first = $xt_old;
                  }
              }
              else {
                  $tmp1=$y;
                  $prev=$this->coords[0][$pnts-1];
                  if( $tmp1==='' || $tmp1===NULL || $tmp1==='X' ) $tmp1 = 'x';
                  if( $prev==='' || $prev===null || $prev==='X' ) $prev = 'x';
  
                  if( is_numeric($y) || (is_string($y) && $y != '-') ) {
                      if( is_numeric($y) && (is_numeric($prev) || $prev === '-' ) ) {
                          $img->StyleLineTo($xt,$yt);
                      }
                      else {
                          $img->SetStartPoint($xt,$yt);
                      }
                  }
                  if( $this->filled && $tmp1 !== '-' ) {
                      if( $tmp1 === 'x' ) {
                          $cord[$idx++] = $cord[$idx-3];
                          $cord[$idx++] = $fillmin;
                      }
                      elseif( $prev === 'x' ) {
                          $cord[$idx++] = $xt;
                          $cord[$idx++] = $fillmin;
                          $cord[$idx++] = $xt;
                          $cord[$idx++] = $yt;
                      }
                      else {
                          $cord[$idx++] = $xt;
                          $cord[$idx++] = $yt;
                      }
                  }
                  else {
                      if( is_numeric($tmp1)  && (is_numeric($prev) || $prev === '-' ) ) {
                          $cord[$idx++] = $xt;
                          $cord[$idx++] = $yt;
                      }
                  }
              }
              $yt_old = $yt;
              $xt_old = $xt;
              $y_old = $y;
  
              $this->StrokeDataValue($img,$this->coords[0][$pnts],$xt,$yt);
  
              ++$pnts;
          }
  
          if( $this->filled  ) {
              $cord[$idx++] = $xt;
              if( $this->fillFromMax ) {
                  $cord[$idx++] = $yscale->scale_abs[1];
              }
              else {
                  if( $min > 0 || $this->fillFromMin ) {
                      $cord[$idx++] = $yscale->Translate($min);
                  }
                  else {
                      $cord[$idx++] = $yscale->Translate(0);
                  }
              }
              if( $this->fillgrad ) {
                  $img->SetLineWeight(1);
                  $grad = new Gradient($img);
                  $grad->SetNumColors($this->fillgrad_numcolors);
                  $grad->FilledFlatPolygon($cord,$this->fillgrad_fromcolor,$this->fillgrad_tocolor);
                  $img->SetLineWeight($this->weight);
              }
              else {
                  $img->SetColor($this->fill_color);
                  $img->FilledPolygon($cord);
              }
              if( $this->weight > 0 ) { 
                  $img->SetLineWeight($this->weight);
                  $img->SetColor($this->color);
                  // Remove first and last coordinate before drawing the line
                  // sine we otherwise get the vertical start and end lines which
                  // doesn't look appropriate
                  $img->Polygon(array_slice($cord,2,count($cord)-4));
              }
          }
  
          if(!empty($this->filledAreas)) {
  
              $minY = $yscale->Translate($yscale->GetMinVal());
              $factor = ($this->step_style ? 4 : 2);
  
              for($i = 0; $i < sizeof($this->filledAreas); ++$i) {
                  // go through all filled area elements ordered by insertion
                  // fill polygon array
                  $areaCoords[] = $cord[$this->filledAreas[$i][0] * $factor];
                  $areaCoords[] = $minY;
  
                  $areaCoords =
                  array_merge($areaCoords,
                  array_slice($cord,
                  $this->filledAreas[$i][0] * $factor,
                  ($this->filledAreas[$i][1] - $this->filledAreas[$i][0] + ($this->step_style ? 0 : 1))  * $factor));
                  $areaCoords[] = $areaCoords[sizeof($areaCoords)-2]; // last x
                  $areaCoords[] = $minY; // last y
  
                  if($this->filledAreas[$i][3]) {
                      $img->SetColor($this->filledAreas[$i][2]);
                      $img->FilledPolygon($areaCoords);
                      $img->SetColor($this->color);
                  }
                  // Check if we should draw the frame.
                  // If not we still re-draw the line since it might have been
                  // partially overwritten by the filled area and it doesn't look
                  // very good.
                  if( $this->filledAreas[$i][4] ) {
                      $img->Polygon($areaCoords);
                  }
                  else {
                      $img->Polygon($cord);
                  }
  
                  $areaCoords = array();
              }
          }
  
          if( $this->mark->type == -1 || $this->mark->show == false )
          return;
  
          for( $pnts=0; $pnts<$numpoints; ++$pnts) {
  
              if( $exist_x ) {
                  $x=$this->coords[1][$pnts];
              }
              else {
                  $x=$pnts+$textadj;
              }
              $xt = $xscale->Translate($x);
              $yt = $yscale->Translate($this->coords[0][$pnts]);
  
              if( is_numeric($this->coords[0][$pnts]) ) {
                  if( !empty($this->csimtargets[$pnts]) ) {
                      if( !empty($this->csimwintargets[$pnts]) ) {
                          $this->mark->SetCSIMTarget($this->csimtargets[$pnts],$this->csimwintargets[$pnts]);
                      }
                      else {
                          $this->mark->SetCSIMTarget($this->csimtargets[$pnts]);
                      }
                      $this->mark->SetCSIMAlt($this->csimalts[$pnts]);
                  }
                  if( $exist_x ) {
                      $x=$this->coords[1][$pnts];
                  }
                  else {
                      $x=$pnts;
                  }
                  $this->mark->SetCSIMAltVal($this->coords[0][$pnts],$x);
                  $this->mark->Stroke($img,$xt,$yt);
                  $this->csimareas .= $this->mark->GetCSIMAreas();
              }
          }
      }
  } // Class
  
  
  //===================================================
  // CLASS AccLinePlot
  // Description:
  //===================================================
  class AccLinePlot extends Plot {
      protected $plots=null,$nbrplots=0;
      private $iStartEndZero=true;
      //---------------
      // CONSTRUCTOR
      function __construct($plots) {
          $this->plots = $plots;
          $this->nbrplots = count($plots);
          $this->numpoints = $plots[0]->numpoints;
  
          // Verify that all plots have the same number of data points
          for( $i=1; $i < $this->nbrplots; ++$i ) {
              if( $plots[$i]->numpoints != $this->numpoints ) {
                  JpGraphError::RaiseL(10003);//('Each plot in an accumulated lineplot must have the same number of data points',0)
              }
          }
  
          for($i=0; $i < $this->nbrplots; ++$i ) {
              $this->LineInterpolate($this->plots[$i]->coords[0]);
          }
      }
  
      //---------------
      // PUBLIC METHODS
      function Legend($graph) {
          foreach( $this->plots as $p ) {
              $p->DoLegend($graph);
          }
      }
  
      function Max() {
          list($xmax) = $this->plots[0]->Max();
          $nmax=0;
          $n = count($this->plots);
          for($i=0; $i < $n; ++$i) {
              $nc = count($this->plots[$i]->coords[0]);
              $nmax = max($nmax,$nc);
              list($x) = $this->plots[$i]->Max();
              $xmax = Max($xmax,$x);
          }
          for( $i = 0; $i < $nmax; $i++ ) {
              // Get y-value for line $i by adding the
              // individual bars from all the plots added.
              // It would be wrong to just add the
              // individual plots max y-value since that
              // would in most cases give to large y-value.
              $y=$this->plots[0]->coords[0][$i];
              for( $j = 1; $j < $this->nbrplots; $j++ ) {
                  $y += $this->plots[ $j ]->coords[0][$i];
              }
              $ymax[$i] = $y;
          }
          $ymax = max($ymax);
          return array($xmax,$ymax);
      }
  
      function Min() {
          $nmax=0;
          list($xmin,$ysetmin) = $this->plots[0]->Min();
          $n = count($this->plots);
          for($i=0; $i < $n; ++$i) {
              $nc = count($this->plots[$i]->coords[0]);
              $nmax = max($nmax,$nc);
              list($x,$y) = $this->plots[$i]->Min();
              $xmin = Min($xmin,$x);
              $ysetmin = Min($y,$ysetmin);
          }
          for( $i = 0; $i < $nmax; $i++ ) {
              // Get y-value for line $i by adding the
              // individual bars from all the plots added.
              // It would be wrong to just add the
              // individual plots min y-value since that
              // would in most cases give to small y-value.
              $y=$this->plots[0]->coords[0][$i];
              for( $j = 1; $j < $this->nbrplots; $j++ ) {
                  $y += $this->plots[ $j ]->coords[0][$i];
              }
              $ymin[$i] = $y;
          }
          $ymin = Min($ysetmin,Min($ymin));
          return array($xmin,$ymin);
      }
  
      // Gets called before any axis are stroked
      function PreStrokeAdjust($graph) {
  
          // If another plot type have already adjusted the
          // offset we don't touch it.
          // (We check for empty in case the scale is  a log scale
          // and hence doesn't contain any xlabel_offset)
  
          if( empty($graph->xaxis->scale->ticks->xlabel_offset) ||
          $graph->xaxis->scale->ticks->xlabel_offset == 0 ) {
              if( $this->center ) {
                  ++$this->numpoints;
                  $a=0.5; $b=0.5;
              } else {
                  $a=0; $b=0;
              }
              $graph->xaxis->scale->ticks->SetXLabelOffset($a);
              $graph->SetTextScaleOff($b);
              $graph->xaxis->scale->ticks->SupressMinorTickMarks();
          }
  
      }
  
      function SetInterpolateMode($aIntMode) {
          $this->iStartEndZero=$aIntMode;
      }
  
      // Replace all '-' with an interpolated value. We use straightforward
      // linear interpolation. If the data starts with one or several '-' they
      // will be replaced by the the first valid data point
      function LineInterpolate(&$aData) {
  
          $n=count($aData);
          $i=0;
  
          // If first point is undefined we will set it to the same as the first
          // valid data
          if( $aData[$i]==='-' ) {
              // Find the first valid data
              while( $i < $n && $aData[$i]==='-' ) {
                  ++$i;
              }
              if( $i < $n ) {
                  for($j=0; $j < $i; ++$j ) {
                      if( $this->iStartEndZero )
                      $aData[$i] = 0;
                      else
                      $aData[$j] = $aData[$i];
                  }
              }
              else {
                  // All '-' => Error
                  return false;
              }
          }
  
          while($i < $n) {
              while( $i < $n && $aData[$i] !== '-' ) {
                  ++$i;
              }
              if( $i < $n ) {
                  $pstart=$i-1;
  
                  // Now see how long this segment of '-' are
                  while( $i < $n && $aData[$i] === '-' ) {
                      ++$i;
                  }
                  if( $i < $n ) {
                      $pend=$i;
                      $size=$pend-$pstart;
                      $k=($aData[$pend]-$aData[$pstart])/$size;
                      // Replace the segment of '-' with a linear interpolated value.
                      for($j=1; $j < $size; ++$j ) {
                          $aData[$pstart+$j] = $aData[$pstart] + $j*$k ;
                      }
                  }
                  else {
                      // There are no valid end point. The '-' goes all the way to the end
                      // In that case we just set all the remaining values the the same as the
                      // last valid data point.
                      for( $j=$pstart+1; $j < $n; ++$j )
                      if( $this->iStartEndZero ) {
                          $aData[$j] = 0;
                      }
                      else {
                          $aData[$j] = $aData[$pstart] ;
                      }
                  }
              }
          }
          return true;
      }
  
      // To avoid duplicate of line drawing code here we just
      // change the y-values for each plot and then restore it
      // after we have made the stroke. We must do this copy since
      // it wouldn't be possible to create an acc line plot
      // with the same graphs, i.e AccLinePlot(array($pl,$pl,$pl));
      // since this method would have a side effect.
      function Stroke($img,$xscale,$yscale) {
          $img->SetLineWeight($this->weight);
          $this->numpoints = count($this->plots[0]->coords[0]);
          // Allocate array
          $coords[$this->nbrplots][$this->numpoints]=0;
          for($i=0; $i<$this->numpoints; $i++) {
              $coords[0][$i]=$this->plots[0]->coords[0][$i];
              $accy=$coords[0][$i];
              for($j=1; $j<$this->nbrplots; ++$j ) {
                  $coords[$j][$i] = $this->plots[$j]->coords[0][$i]+$accy;
                  $accy = $coords[$j][$i];
              }
          }
          for($j=$this->nbrplots-1; $j>=0; --$j) {
              $p=$this->plots[$j];
              for( $i=0; $i<$this->numpoints; ++$i) {
                  $tmp[$i]=$p->coords[0][$i];
                  $p->coords[0][$i]=$coords[$j][$i];
              }
              $p->Stroke($img,$xscale,$yscale);
              for( $i=0; $i<$this->numpoints; ++$i) {
                  $p->coords[0][$i]=$tmp[$i];
              }
              $p->coords[0][]=$tmp;
          }
      }
  } // Class
  
  
  /* EOF */
  ?>