slap, a data directory which contains examples of slap files. These are files associated with the Sparse Linear Algebra Package (SLAP) of Anne Greenbaum and Mark Seager. This package includes a file format that may be used to store matrices externally.
SLAP files begin with a single header line containing five integers. These integers are written in a FORTRAN FORMAT of '(5I10)', that is, five integers, each written into a field of width 10 characters, and right justified. The format is
N NELT ISYM IRHS ISOLNThe interpretation of these values is as follows:
Immediately following the header line comes a series of NELT records, each containing the row, column and value of a nonzero entry of the matrix. Each line is written in a FORTRAN FORMAT of '(1X,I5,1X,I5,1X,E16.7)', that is, a space, a right-justified integer in a field of width 5, a space, another right-justified integer in a field of width 5, a space, and a real number in a field of width 16, with 7 digits after the decimal place and written in an exponential format. For K = 1 to NELT, the format is
IA(K) JA(K) A(K)The interpretation of these values is as follows:
If IRHS = 1, then there follow N records containing a right hand side vector. Each line is written in a FORTRAN FORMAT of '(1X,E16.7)', that is, a space, and a real number in a field of width 16, with 7 digits after the decimal place and written in an exponential format. For I = 1 to N, the format is
RHS(I)
If ISOLN = 1, then there follow N records containing a solution vector. Each line is written in a FORTRAN FORMAT of '(1X,E16.7)', that is, a space, and a real number in a field of width 16, with 7 digits after the decimal place and written in an exponential format. For I = 1 to N, the format is
SOLN(I)
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