Thanks for your answer Andrew.
When I have to remove a basic variable, I fix its bound using the GLP_FX
constant as Heinrich suggested, and when I have to remove a non-basic
constraint, I unbind it using GLP_FR, before removing them from the problem
object in a further iteration where the variable
When I have to remove a basic variable, I fix its bound using the
GLP_FX constant as Heinrich suggested, and when I have to remove a
non-basic constraint, I unbind it using GLP_FR, before removing them
from the problem object in a further iteration where the variable is
no more basic or
Please, add the missing information to glpk.pdf as indicated below:
Okay.
glp_del_rows invalidates the basis factorization.
glp_del_cols invalidates the basis factorization if the column is basic.
More precisely, any change in the problem object that affects the basis
matrix (adding rows,
Now my question is: should I solve the model from scratch in the case
I have to remove a lot of variables?
Generally, not.
Or is there a parameter configuration I should use in my specific
case?
Glp_simplex always starts the search from the current basis which is
provided in glp_prob by
Hello,
I embed the linear GLPK solver into my own Branch-and-Price algorithm and
until now I am very satisfied with the performance and stability of the
tool.
Lately I tested my algorithm on greater models (typically about 5600
constraints and 57000 variables) and I'd like to know if there is
@Andrew:
Please, add the missing information to glpk.pdf as indicated below:
glp_del_rows invalidates the basis factorization.
glp_del_cols invalidates the basis factorization if the column is basic.
After invalidation of the basis factorization glp_warm_up has to be
called before calling
Hello Emanuele
You should join the mailing list if you wish to post.
Moreover, your subject line Suggestions for GLPK is
not especially clear and it would help both you and
those later wishing to search the archives if your post
was more precisely titled.
I've been trying GLPK for a month now and I have some
suggestions for
enhancement that would make the package more
attractive (at least to me!).
Thank you for suggestions.
1) The possibility to specify that the matrix is
symmetric and therefore use
half the storage.
I've never met
