ChartDirector 7.0 (PHP Edition)

Heat Map Cell Labels




This example demonstrates adding labels to the cells, adding gaps between cells and using a custom color scale.

This example is similar to Discrete Heat Map, with the following additions:

Source Code Listing

[File: phpdemo/heatmapcelllabels.php]
<?php require_once("../lib/phpchartdir.php"); # The x-axis and y-axis labels $xLabels = array("A", "B", "C", "D", "E", "F", "G", "H", "I", "J"); $yLabels = array("0", "1", "2", "3", "4", "5", "6", "7", "8", "9"); # Random data for the 10 x 10 cells $rand = new RanSeries(2); $zData = $rand->get2DSeries(count($xLabels), count($yLabels), 0, 100); # We set the middle 5 x 5 cells to NoValue to remove them from the chart for($x = 3; $x < 7; ++$x) { for($y = 3; $y < 7; ++$y) { $zData[$y * count($xLabels) + $x] = NoValue; } } # Create an XYChart object of size 480 x 540 pixels. $c = new XYChart(480, 540); # Set the plotarea at (50, 40) and of size 400 x 400 pixels. Set the background, border, and grid # lines to transparent. $p = $c->setPlotArea(50, 40, 400, 400, -1, -1, Transparent, Transparent); # Create a discrete heat map with 10 x 10 cells $layer = $c->addDiscreteHeatMapLayer($zData, count($xLabels)); # Set the x-axis labels. Use 8pt Arial Bold font. Set axis stem to transparent, so only the labels # are visible. Set 0.5 offset to position the labels in between the grid lines. Position the x-axis # at the top of the chart. $c->xAxis->setLabels($xLabels); $c->xAxis->setLabelStyle("Arial Bold", 8); $c->xAxis->setColors(Transparent, TextColor); $c->xAxis->setLabelOffset(0.5); $c->xAxis->setTitle("X axis title placeholder", "Arial Bold", 12); $c->setXAxisOnTop(); # Set the y-axis labels. Use 8pt Arial Bold font. Set axis stem to transparent, so only the labels # are visible. Set 0.5 offset to position the labels in between the grid lines. Reverse the y-axis # so that the labels are flowing top-down instead of bottom-up. $c->yAxis->setLabels($yLabels); $c->yAxis->setLabelStyle("Arial Bold", 8); $c->yAxis->setColors(Transparent, TextColor); $c->yAxis->setLabelOffset(0.5); $c->yAxis->setTitle("Y axis title placeholder", "Arial Bold", 12); $c->yAxis->setReverse(); # Set a 3-pixel gap between cells $layer->setCellGap(3); # Use the z value as the cell label $layer->setDataLabelFormat("{z|0}"); # Position the color axis 20 pixels below the plot area and of the width as the plot area. Put the # labels at the bottom side of the color axis. Use 8pt Arial Bold font for the labels. $cAxis = $layer->setColorAxis($p->getLeftX(), $p->getBottomY() + 20, TopLeft, $p->getWidth(), Bottom ); $cAxis->setLabelStyle("Arial Bold", 8); $cAxis->setTitle("Color legend title placeholder", "Arial Bold", 12); # Set the color stops and scale of the color axis $colorScale = array(0, 0x00ff00, 50, 0xffff00, 80, 0xff6600, 100, 0xff0000); $cAxis->setColorScale($colorScale); $cAxis->setLinearScale(0, 100, 10); # Output the chart $viewer = new WebChartViewer("chart1"); $viewer->setChart($c, SVG); # Include tool tip for the chart $viewer->setImageMap($c->getHTMLImageMap("", "", "title='<*cdml*>({xLabel}, {yLabel}) = {z|2}'")); ?> <!DOCTYPE html> <html> <head> <title>Heat Map Cell Labels</title> <!-- Include ChartDirector Javascript Library to support chart interactions --> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <div style="font:bold 18pt verdana;"> Heat Map Cell Labels </div> <hr style="border:solid 1px #000080; background:#000080" /> <div style="font:10pt verdana; margin-bottom:1.5em"> <a href="viewsource.php?file=<?=basename(__FILE__)?>">View Chart Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <?php echo $viewer->renderHTML(); ?> </body> </html>