This function will draw an area between two threshold. Using areas can help you to highlight specific values. It is possible to tune the rendering by playing with the $Format array. To learn more about this please read the Format array guide.

drawScatterThresholdArea($Value1,$Value2,$Format="");

Where :


This function returns an array containing the Y position of the up & down boundaries of the area.


It is possible to customize the way your threshold will be rendered by playing with this array. Providing a detailled configuration is not mandatory, by default the line will be drawn dashed in red.

 /* pChart library inclusions */ 
 include("../class/pData.class.php"); 
 include("../class/pDraw.class.php"); 
 include("../class/pImage.class.php"); 
 include("../class/pScatter.class.php"); 

 /* Create the pData object */ 
 $myData = new pData();   

 /* Create the X axis and the binded series */ 
 $myData->createFunctionSerie("X","1/z",array("MinX"=>-10,"MaxX"=>10,"XStep"=>1));
 $myData->setAxisName(0,"x = 1/z"); 
 $myData->setAxisXY(0,AXIS_X); 
 $myData->setAxisPosition(0,AXIS_POSITION_BOTTOM); 

 /* Create the Y axis */ 
 $myData->createFunctionSerie("Y","z",array("MinX"=>-10,"MaxX"=>10,"XStep"=>1));
 $myData->setSerieOnAxis("Y",1); 
 $myData->setAxisName(1,"y = z"); 
 $myData->setAxisXY(1,AXIS_Y); 
 $myData->setAxisPosition(1,AXIS_POSITION_RIGHT); 

 /* Create the Y axis */ 
 $myData->createFunctionSerie("Y2","z*z*z",array("MinX"=>-10,"MaxX"=>10,"XStep"=>1));
 $myData->setSerieOnAxis("Y2",2); 
 $myData->setAxisName(2,"y = z*z*z"); 
 $myData->setAxisXY(2,AXIS_Y); 
 $myData->setAxisPosition(2,AXIS_POSITION_LEFT); 

 /* Create the 1st scatter chart binding */ 
 $myData->setScatterSerie("X","Y",0); 
 $myData->setScatterSerieDescription(0,"Pass A"); 
 $myData->setScatterSerieTicks(0,4); 
 $myData->setScatterSerieColor(0,array("R"=>0,"G"=>0,"B"=>0)); 

 /* Create the 2nd scatter chart binding */ 
 $myData->setScatterSerie("X","Y2",1); 
 $myData->setScatterSerieDescription(1,"Pass B"); 
 $myData->setScatterSerieTicks(1,4); 
 $myData->setScatterSerieColor(1,array("R"=>120,"G"=>0,"B"=>255)); 

 /* Create the pChart object */ 
 $myPicture = new pImage(400,400,$myData); 

 /* Draw the background */ 
 $Settings = array("R"=>170, "G"=>183, "B"=>87, "Dash"=>1, "DashR"=>190, "DashG"=>203, "DashB"=>107);
 $myPicture->drawFilledRectangle(0,0,400,400,$Settings); 

 /* Overlay with a gradient */ 
 $Settings = array("StartR"=>219, "StartG"=>231, "StartB"=>139, "EndR"=>1, "EndG"=>138, "EndB"=>68, "Alpha"=>50);
 $myPicture->drawGradientArea(0,0,400,400,DIRECTION_VERTICAL,$Settings); 
 $myPicture->drawGradientArea(0,0,400,20,DIRECTION_VERTICAL,array("StartR"=>0,"StartG"=>0,"StartB"=>0, "EndR"=>50,"EndG"=>50,"EndB"=>50,"Alpha"=>80));
 
 /* Write the picture title */  
 $myPicture->setFontProperties(array("FontName"=>"../fonts/Silkscreen.ttf","FontSize"=>6));
 $myPicture->drawText(10,13,"createFunctionSerie() - Functions computing",array("R"=>255,"G"=>255,"B"=>255));
 
 /* Add a border to the picture */ 
 $myPicture->drawRectangle(0,0,399,399,array("R"=>0,"G"=>0,"B"=>0)); 
 /* Set the default font */ 
 $myPicture->setFontProperties(array("FontName"=>"../fonts/pf_arma_five.ttf","FontSize"=>6));
   
 /* Set the graph area */ 
 $myPicture->setGraphArea(50,50,350,350); 

 /* Create the Scatter chart object */ 
 $myScatter = new pScatter($myPicture,$myData); 

 /* Draw the scale */ 
 $myScatter->drawScatterScale(array("XMargin"=>10,"YMargin"=>10,"Floating"=>TRUE));
 
 /* Turn on shadow computing */ 
 $myPicture->setShadow(TRUE,array("X"=>1,"Y"=>1,"R"=>0,"G"=>0,"B"=>0,"Alpha"=>10));
 
 /* Draw the 0/0 lines */ 
 $myScatter->drawScatterThreshold(0,array("AxisID"=>0,"R"=>0,"G"=>0,"B"=>0,"Ticks"=>10));
 $myScatter->drawScatterThreshold(0,array("AxisID"=>1,"R"=>0,"G"=>0,"B"=>0,"Ticks"=>10));
 
 /* Draw a treshold area */ 
 $myScatter->drawScatterThresholdArea(-0.1,0.1,array("AreaName"=>"Error zone"));
 
 /* Draw a scatter plot chart */ 
 $myScatter->drawScatterLineChart(); 
 $myScatter->drawScatterPlotChart(); 

 /* Draw the legend */ 
 $myScatter->drawScatterLegend(300,380,array("Mode"=>LEGEND_HORIZONTAL,"Style"=>LEGEND_NOBORDER));
 
 /* Render the picture (choose the best way) */ 
 $myPicture->autoOutput("pictures/example.createFunctionSerie.scatter.png");