# Drawing a scatter threshold chart [Reference](http://wiki.pchart.net/doc.scatter.drawscatterthreshold.html) ```php require '/path/to/your/vendor/autoload.php'; use CpChart\Chart\Scatter; use CpChart\Data; use CpChart\Image; /* Create the Data object */ $data = new Data(); /* Create the X axis and the binded series */ $data->createFunctionSerie("X", "1/z", ["MinX" => -10, "MaxX" => 10, "XStep" => 1]); $data->setAxisName(0, "x = 1/z"); $data->setAxisXY(0, AXIS_X); $data->setAxisPosition(0, AXIS_POSITION_BOTTOM); /* Create the Y axis */ $data->createFunctionSerie("Y", "z", ["MinX" => -10, "MaxX" => 10, "XStep" => 1]); $data->setSerieOnAxis("Y", 1); $data->setAxisName(1, "y = z"); $data->setAxisXY(1, AXIS_Y); $data->setAxisPosition(1, AXIS_POSITION_RIGHT); /* Create the Y axis */ $data->createFunctionSerie("Y2", "z*z*z", ["MinX" => -10, "MaxX" => 10, "XStep" => 1]); $data->setSerieOnAxis("Y2", 2); $data->setAxisName(2, "y = z*z*z"); $data->setAxisXY(2, AXIS_Y); $data->setAxisPosition(2, AXIS_POSITION_LEFT); /* Create the 1st scatter chart binding */ $data->setScatterSerie("X", "Y", 0); $data->setScatterSerieDescription(0, "Pass A"); $data->setScatterSerieTicks(0, 4); $data->setScatterSerieColor(0, ["R" => 0, "G" => 0, "B" => 0]); /* Create the 2nd scatter chart binding */ $data->setScatterSerie("X", "Y2", 1); $data->setScatterSerieDescription(1, "Pass B"); $data->setScatterSerieTicks(1, 4); $data->setScatterSerieColor(1, ["R" => 120, "G" => 0, "B" => 255]); /* Create the Image object */ $image = new Image(400, 400, $data); /* Draw the background */ $settings = ["R" => 170, "G" => 183, "B" => 87, "Dash" => 1, "DashR" => 190, "DashG" => 203, "DashB" => 107]; $image->drawFilledRectangle(0, 0, 400, 400, $settings); /* Overlay with a gradient */ $image->drawGradientArea(0, 0, 400, 400, DIRECTION_VERTICAL, [ "StartR" => 219, "StartG" => 231, "StartB" => 139, "EndR" => 1, "EndG" => 138, "EndB" => 68, "Alpha" => 50 ]); $image->drawGradientArea(0, 0, 400, 20, DIRECTION_VERTICAL, [ "StartR" => 0, "StartG" => 0, "StartB" => 0, "EndR" => 50, "EndG" => 50, "EndB" => 50, "Alpha" => 80 ]); /* Write the picture title */ $image->setFontProperties(["FontName" => "Silkscreen.ttf", "FontSize" => 6]); $image->drawText(10, 13, "createFunctionSerie() - Functions computing", [ "R" => 255, "G" => 255, "B" => 255 ]); /* Add a border to the picture */ $image->drawRectangle(0, 0, 399, 399, ["R" => 0, "G" => 0, "B" => 0]); /* Set the default font */ $image->setFontProperties(["FontName" => "pf_arma_five.ttf", "FontSize" => 6]); /* Set the graph area */ $image->setGraphArea(50, 50, 350, 350); /* Create the Scatter chart object */ $myScatter = new Scatter($image, $data); /* Draw the scale */ $myScatter->drawScatterScale(["XMargin" => 10, "YMargin" => 10, "Floating" => true]); /* Turn on shadow computing */ $image->setShadow(true, ["X" => 1, "Y" => 1, "R" => 0, "G" => 0, "B" => 0, "Alpha" => 10]); /* Draw the 0/0 lines */ $myScatter->drawScatterThreshold(0, ["AxisID" => 0, "R" => 0, "G" => 0, "B" => 0, "Ticks" => 10]); $myScatter->drawScatterThreshold(0, ["AxisID" => 1, "R" => 0, "G" => 0, "B" => 0, "Ticks" => 10]); /* Draw a treshold area */ $myScatter->drawScatterThresholdArea(-0.1, 0.1, ["AreaName" => "Error zone"]); /* Draw a scatter plot chart */ $myScatter->drawScatterLineChart(); $myScatter->drawScatterPlotChart(); /* Draw the legend */ $myScatter->drawScatterLegend(300, 380, ["Mode" => LEGEND_HORIZONTAL, "Style" => LEGEND_NOBORDER]); /* Render the picture (choose the best way) */ $image->autoOutput("example.createFunctionSerie.scatter.png"); ```