GAMS — The Solver Manuals - Available Software

92 COIN-OR
mumps pivtol: Pivot tolerance for the linear solver MUMPS.
A smaller number pivots for sparsity, a larger number pivots for stability. This option is only available if Ipopt
has been compiled with MUMPS. The valid range for this real option is 0 ≤ mumps pivtol ≤ 1 and its default
value is 1 · 10 −06 .
mumps pivtolmax: Maximum pivot tolerance for the linear solver MUMPS.
Ipopt may increase pivtol as high as pivtolmax to get a more accurate solution to the linear system. This
option is only available if Ipopt has been compiled with MUMPS. The valid range for this real option is 0 ≤
mumps pivtolmax ≤ 1 and its default value is 0.1.
mumps scaling: Controls scaling in MUMPS
This is ICTL(8) in MUMPS. The valid range for this integer option is −2 ≤ mumps scaling ≤ 7 and its default
value is 7.
Pardiso Linear Solver
pardiso iter tol exponent:
The valid range for this integer option is −inf < pardiso iter tol exponent < +inf and its default value is
−14.
pardiso iterative:
The default value for this string option is ”no”.
pardiso matching strategy: Matching strategy to be used by Pardiso
This is IPAR(13) in Pardiso manual. This option is only available if Ipopt has been compiled with Pardiso. The
default value for this string option is ”complete+2x2”.
Possible values:
• complete: Match complete (IPAR(13)=1)
• complete+2x2: Match complete+2x2 (IPAR(13)=2)
• constraints: Match constraints (IPAR(13)=3)
pardiso out of core power: Enables out-of-core variant of Pardiso
Setting this option to a positive integer k makes Pardiso work in the out-of-core variant where the factor is split
in 2 k subdomains. This is IPARM(50) in the Pardiso manual. This option is only available if Ipopt has been
compiled with Pardiso. The valid range for this integer option is 0 ≤ pardiso out of core power < +inf and
its default value is 0.
pardiso redo symbolic fact only if inertia wrong: Toggle for handling case when elements were perturbed
by Pardiso.
This option is only available if Ipopt has been compiled with Pardiso. The default value for this string option is
”no”.
Possible values:
• no: Always redo symbolic factorization when elements were perturbed
• yes: Only redo symbolic factorization when elements were perturbed if also the inertia was wrong