TimeChart is a simple PHP library for drawing time series charts (events sampled through a time interval). It was originally developed for PgMonitor and OpenStats projects (also hosted here on Sourceforge.net), is distributed under GNU General Public License v2, and has several interesting features

• each of the time series (datasets) may be sampled independently (the datasets may not be aligned)
• the x-coordinates (time) may be distributed arbitrarily - unevenly, not aligned to "nice" values (whole minutes / hours etc.)
• the time series may be automatically aggregated (hour averages, etc.)
• implemented in pure PHP (requires just GD library, nothing else)

First production version was just released

I'm happy to announce that a first production/stable version v1.0 of the library was released today (October 21, 2009). Compared to the beta version, numerous several bugs were fixed, and two interesting features were added (proper handling of missing data, normalization) and as you can see from the screenshorts below, legend is placed outside the charting area (so that it does not cover parts of the chart).

This is not a generic charting library

Time series chart is the only supported chart type - if you need a generic charting library (for example to draw bar or pie charts), this library is not what you are looking for. There are other more suitable projects, for example:

• pChart - a very nice charting library
• libchart - not as nice as pchart, but still quite useful
• ChartDirector - a very nice commercial library, I've been using it for a long time, very fast (uses a C library), many languages supported (PHP, Java, ColdFusion, ...)
• JpGraph - another quite nice commercial library
• Open Flash Chart - a very nice library for building SWF charts
• matplotlib - a very nice plotting library written in Python

Screenshots

The following screenshots contain 'random' data (see the trunk/examples directory for the script used to build them).

This is how the charts were drawn before the v1.0:

Current status

Currently the library is usable i.e. it draws the charts correctly in most cases, but there is plenty of features to improve etc.

Links and contacts

• This library was developed for PgMonitor and OpenStats projects.
• If you have issues with this library / are interested in this library / would like to join this project, contatct me on timechart@fuzzy.cz.
• Subversion contains API docs built using phpDocumentor.