Commit Graph

10 Commits (e9ffb16ec62b8e6cba2ca1dc84e8c4c65d8a45f0)

Author SHA1 Message Date
Sébastien Villemot 82a2aeaae4
Block trust region MEX: gracefully handle the singular Jacobian case
When the Jacobian of the problem is singular, compute a solution to the least
squares problem instead of crashing.

Closes #1889
2023-09-26 15:30:33 +02:00
Sébastien Villemot 9e7e069aa8
Fortran: use standard-compliant ieee_is_nan() instead of GNU extension isnan() 2023-09-16 14:25:40 +02:00
Sébastien Villemot b1db895dee
block_trust_region MEX: remove unused parameter 2023-07-27 17:29:31 +02:00
Sébastien Villemot 62c2881bc2
Fortran 2018 modernization: use the extended “implicit none” syntax
The statement “implicit none” forbids implicit typing of variables, but not
implicit procedure declaration. The new “implicit none (type, external)” syntax
forbids both, and is thus safer.
2023-04-14 15:06:37 +02:00
Stéphane Adjemian (Ryûk) b9bc1e7cb1
Revert update if residuals or jacobian have NaNs (block_trust_region). 2022-03-25 19:42:40 +01:00
Stéphane Adjemian (Ryûk) 79cad99446
Harmonise exit codes and fix convergence test. 2022-03-25 19:42:40 +01:00
Stéphane Adjemian (Ryûk) e72dde69d3
Add option for trust region algorithm (mex).
trust_region_initial_step_bound_factor is determinining thye initial
step bound. Default value is 100 (previous hard coded value was 1).
2021-07-23 19:44:16 +02:00
Sébastien Villemot 766fff88f6
Use secure URL for link to GNU licenses 2021-06-09 17:35:05 +02:00
Sébastien Villemot dc2695a11f
mjdgges and block_trust_region MEX: optimise by marking some function arguments as contiguous
This avoids unnecessary array copies before calling BLAS/LAPACK functions.
2021-06-04 12:58:36 +02:00
Sébastien Villemot 6a26926892
Add new block_trust_region MEX
This MEX solves nonlinear systems of equations using a trust region algorithm.
The problem is subdivided in smaller problems by doing a block
triangularisation of the Jacobian at the guess value, using the
Dulmage-Mendelsohn algorithm.

The interface of the MEX is simply:

  [x, info] = block_trust_region(f, guess_value);

Where f is either a function handle or a string designating a function.
f must take one argument (the evaluation point), and return either one or two
arguments (the residuals and, optionally, the Jacobian).

On success, info=0; on failure, info=1.
2019-12-03 16:17:16 +01:00