Gwyddion is a modular program for scanning probe microscopy (spm) data visualization and analysis. it is primarily intended for analysis of height field data obtained by microscopy techniques like
* atomic force microscopy (afm),
* magnetic force microscopy (mfm),
* scanning tunneling microscopy (stm),
* near-field scanning optical microscopy (snom or nsom)
and others. however, it can be used for arbitrary height field and image analysis.

this package contains the html api documentation of all the gwyddion libraries. there is also a tutorial on writing gwyddion modules included.