The main input file for a spiffe run consists of a series of namelists, which function as commands. Most of the namelists direct spiffe to set up to run in a certain way. A few are “action” commands that begin the actual simulation. FORTRAN programmers should note that, unlike FORTRAN namelists, these namelists need not come in a predefined order; spiffe is able to detect which namelist is next in the file and process appropriately.
Each namelist has a number of variables associated with it, which are used to control details of the run. These variables come in three data types: (1) long, for the C long integer type, (2) double, for the C double-precision floating point type, and (3) STRING, for a character string enclosed in double quotation marks. All variables have default values, which are listed on the following pages. STRING variables often have a default value listed as NULL, which means no data; this is quite different from the value “”, which is a zero-length character string. long variables are often used as logical flags, with a zero value indicating false and a non-zero value indicating true.
On the following pages the reader will find individual descriptions of each of the namelist commands and their variables. Each description contains a sequence of the form
This summarizes the parameters of the namelist. Note, however, that the namelists are invoked in the form
The square-brackets enclose an optional component. Not all namelists require variables to be given–the defaults may be sufficient. However, if a variable name is given, it must have a value. Values for STRING variables must be enclosed in double quotation marks. Values for double variables may be in floating-point, exponential, or integer format (exponential format uses the ‘e’ character to introduce the exponent).