Sparkline Creation Using PHP

Sparkline graphs have had a bit of press lately, so I’ve been playing about with generating them on my commutes to and from work.

If you’ve not heard of them before, a Sparkline is a small graph that is often used inline with text.

I’ve been using PHP, so I’ve created a simple class called Spark, with a single static method called line. This returns a simple string as an inline graph from an array of values that have been passed in.

Sparkline Examples

Here’s an example plotting a simple staircase type graph.


echo Spark::line(array(1, 2, 3, 4, 5, 6, 7, 8)) . "n";

> ▁▂▃▄▅▆▇█

Here’s an example plotting a cosine wave.

$cos = array();
for($i=0; $i <= 360; $i=$i+20) {
    $cos[] = cos($i * M_PI / 180);
echo Spark::line($cos) . "n";

> ██▇▆▅▄▃▂▁▁▁▂▃▄▅▆▇██


The code is available on GitHub as php-spark, and is free to use. It was inspired by a simple project for Go called Spark, which was inspired from elsewhere.