Parameter File

 

   

Since the parameter list of the main command in spectral analysis MODEL/SPECTRUM is only a list of file names all other input like the model with its parameters and the parameters controlling the program flow are buried in the parameter file. This is (for easy handling) an ASCII file, which can be edited with a common editor like edt or vi. In a MIDAS session it is possible to create a standard parameter file by using the EXSAS command

CREATE/PARFIL fit parameter_file_name ? [parameter] [value] [expert_flag],

where the file name has to be given while a parameter name, its value, and the expert flag are optional. By using the expert option (any letter) all comment explaining the keywords is skipped.

In the following a short description of the syntax of the parameter file is given.  

• The whole text is not case sensitive. Small and capital letters are allowed.
• Each command line of the parameter file will be executed (interpreted) sequentially. It consists of a keyword (action)   followed by a list of parameters (information):

  KEYWORD parameter_1 parameter_2 ...... [parameter_n]

  Parameters can be mandatory (no bracket) or optional (square brackets [...]). Usually they have proper default values. These keywords can be omitted if their default values are chosen. A parameter list can also be empty. Keyword and parameters are separated by blanks.

• There are general keywords and keywords related to a theoretical model. All lines with general keywords must appear in front of lines with model related keywords. Their order is not important. Lines with model related keywords have a strict order and appear as a whole block at the end of the parameter file.
• Any comment is allowed, a whole line as well as an appendix. A comment always begins with a exclamation mark ``!'' and will be ignored by the interpreter. The exclamation mark can also be used for fast editing by adding or canceling it.
• Keywords can be abbreviated sensibly.
• A blank line is allowed.

 
• General Keywords
• Model related Keywords
• Additive models
• Additive Models (normalized to energy flux)
• Additive Models (normalized to luminosity, )
• Multiplicative Models