[SCIP] SCIPchgReoptObjective() without resetting other variable coeffs

[Ambros Gleixner]

Hi Christopher,

No, but you are correct that this is a good feature request.  It is a 
bit tricky to implement (but not impossible) because of the link between 
original and transformed variables.

If you are worried about overhead for memory allocation, this should be 
solved by using SCIPallocCleanBufferArray(), see

https://scipopt.org/doc/html/group__PublicMemoryMethods.php#ga11c9a6e3b9eb81c15d84e2ef636c40d0

and

https://scipopt.org/doc/html/MEMORY.php

Important: You have to reset the changed entries of the array to zero 
before freeing it.

Best,
Ambros


Am 12.07.2023 um 17:06 schrieb Christopher G:
> Good day SCIP community,
> 
> currently I try to use the reoptimization feature of SCIP to
> accelerate the consecutive solving process of my pricing problems in a B&P
> algorithm. I was wondering whether the method SCIPchgReoptObjective(..) has a
> counterpart which can be used to adapt the objective function coefficients for a
> set of variables while not resetting the coefficients of all other variables.
> 
> Since I don't have contiguous memory for all the coefficients of all my
> variables in my pricing problem, I have to allocate a (rather big) chunk of
> memory that contains such coefficients in each iteration of my pricing. This is
> rather cumbersome and I'd like to avoid this.
> 
> Best,
> Christopher
> 
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