An EIS FITS file is read into an IDL object with:
IDL> data=obj_new('eis_data',filename)
where 'filename' is the name of the level-1 file (a level-0 file can be read in the same way). Information can be extracted from the object via a large number of object methods.
The document below details software available in the EIS Solarsoft tree for fitting Gaussians to EIS data.
Gaussian fitting for the Hinode/EIS mission
Examples for using the routine eis_auto_fit to automatically fit Gaussians across a raster are given in the document below.
Gaussian fitting examples using eis_auto_fit