Mega Code Archive
Simple Horizontal Bar Chart using GD
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<?php
function makeChart($info, $name)
{
// store the keys in separate array for display as label
$keys = array_keys($info);
// Set the maximum
$max = max($info);
// Determine how many bars to create
$n = count($info);
// set up image
$height = $n*100+1;
$width = 600;
$barstart = 100;
$barwidth = 580;
$im = ImageCreate($width+1, $height+1);
$white = ImageColorAllocate ($im, 255, 255, 255);
$black = ImageColorAllocate ($im, 0, 0, 0);
$blue = ImageColorAllocate($im, 0,0,255);
// Create initial image w/borders
ImageFilledRectangle($im, 0, 0, $width, $height,$white);
ImageRectangle($im, 0, 0, $width,$height,$black);
$horiz = 0;
// for each value divide chart and draw bar
for ($i = 0; $i < $n; $i++ )
{
// Print division line
ImageLine($im, 0, $horiz, $width-1, $horiz, $black);
// get and print label
$label = $keys[$i];
ImageString($im, 4, 10, $horiz+5, $label, $blue);
// print value
ImageString($im, 30, 10, $horiz+75, $info[$keys[$i]], $black);
// draw outline of entire bar
ImageRectangle($im, $barstart, $horiz+15, $barwidth,$horiz+75,$black);
// Standardize the values. Max will fill all of bar
$perc = $info[$keys[$i]]/$max;
$filled = ($barwidth-$barstart)*$perc;
// Draw filled bar
ImageFilledRectangle($im, $barstart, $horiz+15, $barstart+$filled,$horiz+75,$blue);
// Move down to next area
$horiz += 100;
}
// output image
ImagePng ($im,$name);
// clean up
ImageDestroy($im);
}
?>
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