Purpose
Instructs the Optimizer to read in a previously saved
basis from a file.
Synopsis
int XPRS_CC XPRSreadbasis(XPRSprob prob, const char *filename, const char *flags);
READBASIS [-flags] [filename]
Arguments
|
prob
|
The current problem.
|
|
filename
|
A string of up to 200 characters containing the file name from which the basis is to be read. If omitted, the default problem_name is used with a .bss extension.
|
|
flags
|
Flags to pass to XPRSreadbasis (READBASIS):
|
i
|
output the internal presolved basis.
|
|
t
|
input a compact advanced form of the basis;
|
|
Example 1 (Library)
If an advanced basis is available for the current problem the Optimizer input might
be:
XPRSreadprob(prob,"filename","");
XPRSreadbasis(prob,"","");
XPRSmaxim(prob,"g");
This reads in a matrix file, inputs an advanced starting basis and maximizes the MIP.
Example 2 (Console)
An equivalent set of commands for the Console user may look like:
READPROB
READBASIS
MAXIM -g
Further information
1. The only check done when reading compact basis is that the number of rows and columns in the basis agrees with the current
number of rows and columns.
2. XPRSreadbasis (READBASIS) will read the basis for the original
problem even if the matrix has been presolved. The Optimizer will read the basis, checking that it
is valid, and will display error messages if it detects inconsistencies.
Related topics
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