For installation instructions see the INSTALL file.

It is important that the file Sources_DB.lib is in the same directory from where you run the programm. This file is the database of the sources and the format is the following:
   First line: integer with the number of sources to read
   then for each source:
      name of the source and number of gammas
      gammas energies
      gammas intensities
      gammas intensities errors

In the folder there is a file named "Eu152_sample.dat" for test reasons.

Run the programm, choose the source measured, press "open data file" and give the file with the data (for example Eu152_sample.dat), set Activity, Activity error and measurement time and press "calculate efficiencies".
Following select the function to fit and press "fit".