As before, the user must prepare an input file, the SEIF (Standard Element type Input Format) file, consisting of indicator and data cards. The former contain a simple keyword to specify the type of data that follows. Possible indicator cards are given in Figure 4.1.
Indicator cards must appear in the order shown. The cards TEMPORARIES, GLOBALS and INDIVIDUALS are optional.
The data cards are of two kinds. The first are like those described in Section 3.1. The others use four fields, fields 1, 2 and 3, as before, and field 7 which starts in column 25 and is 41 characters long. This last field is used to hold arithmetic expressions. An arithmetic expression is as defined in the Fortran programming language standard (ANSI X3.9-1978). We allow the use of any of the language's intrinsic functions in such an expression. Continuation of an expression over at most nineteen lines is also permitted.