This is a collection of test suites to check the accuracy of the pkdgrav/gasoline/changa series of N-body codes. Most tests require the reading and writing of "tipsy" format data.

The array subdirectory contains a collection of C programs to manipulate and compare "tipsy array" format files.

The forces subdirectory contains tests of the gravitational force accuracy.

The density subdirectory contains tests of the kernel smoothing.