📢 #ISMP2027 comes to Amsterdam!
The 26th International Symposium on Mathematical Programming will be held July 25–30, 2027.
Join researchers from around the world to discuss advances, challenges, and opportunities in the theory and practice of mathematical optimization.
🔗 ismp2027.mathopt.nl
#MOS
I'm not sure about Gurobi, but for SCIP I suspect the natural dates formulation of the single machine scheduling problem with cuts based on release times could work:
pure.tue.nl/ws/portalfil...
Just access of any random memory location. This blog series explains it quite well:
www.ilikebigbits.com/2014_04_21_m...
I think the standard model of computation is partly to blame here. Especially O(1) memory access is not really realistic in practice and is closer to to O(sqrt(N)) in practice.
📚 New Arxiv Paper
Title: Circuit Diameter of Polyhedra is Strongly Polynomial
Authors: Bento Natura
Read more: https://arxiv.org/abs/2602.06958
Of course, most papers do define the variables and their meaning in the text above the model. But I think the latter ordering would still be easier to read if you just want to glance at the model.
The order 'objective - constraints - variables' that academic papers use to describe mathematical optimization problems is inconvenient, as it places the objective before you even know what the variables are. Wouldn't 'variables - constraints - objective' be a more natural progression?
130k lines of formal topology in two weeks: Simple and cheap autoformalization for everyone? ~ Josef Urban. arxiv.org/abs/2601.032... #ITP #Mizar #LLMs #Math #Autoformalization
Given both your recent results, are you still motivated to investigate the simplex method further, or do you want to move on to new questions and topics?
The SCIP 10 optimization suite has many new interesting features and is fully open source. For binaries and downloads, check www.scipopt.org/index.php#do...
📚 New Arxiv Paper
Title: Geometry of the Reformulation-Linearization-Technique: Domination of Disjunctions
Authors: Hugo A. Hof, Matthias Walter
Read more: https://arxiv.org/abs/2511.13805
I shouldn't be surprised by this, but I just learned that Nvidia and AMD both disable FP64 performance units in their consumer cards so scientists and companies have to buy the high end ones at 5-10x the price. It's a valid business model but unfortunate for hobbyists like me who just want to try.
📚 New Arxiv Paper
Title: Linear Programming Hierarchies Collapse under Symmetry
Authors: Yuri Faenza, V\'ictor Verdugo, Jos\'e Verschae, Mat\'ias Villagra
Read more: https://arxiv.org/abs/2511.07766
Mostly deterministic RO with uncertainty sets (rather than distributionally RO), which can be formulated as some kind of Mixed Integer Program (does not need to be linear). Most interesting would be instances derived from real-world applications.
The only thing I could find is robust-optimization.com/instances/ , which collects instances from a few papers. Unfortunately, there seems to be no standardized data format for robust optimization problems.
Does there exist a commonly used public instance benchmark set for robust optimization? Or sets of instances which are frequently used within the literature?
This was hard work but now we are happy!
The #BOBILib paper has today been accepted for publication in Mathematical Programming Computation!
Here's the final version of the preprint: optimization-online.org/wp-content/u...!
And here's the website bobilib.org!
Spread the word and use it! :-)
🔄 Updated Arxiv Paper
Title: Implied Integrality in Mixed-Integer Optimization
Authors: Rolf van der Hulst, Matthias Walter
Read more: https://arxiv.org/abs/2504.07209
At least on Linux there seem to exist specialized fast timing functions: see stackoverflow.com/a/47003703 , which recommends to use 'clock_gettime()' and claims it only takes 3-5 nanoseconds on their system. I think it is likely that alternative calls exist in other operating systems.
What kind of crazy FPS are you running at where a syscall is too expensive? In my experience, most syscalls take on the order of 100 - 1000 cycles, which would take less than a microsecond on a modern cpu.
This is now out, we're super proud to have won the Land-Doig MIP competition prize for our algorithm for mixed-integer quadratic optimization!
passagemath 10.5.27 contains (a preliminary version of) the new package passagemath-cmr, an interface to the Combinatorial Matrix Recognition library by Matthias Walter et al., implementing Seymour's decomposition of TU matrices etc.
pypi.org/project/pass...
#Python #SageMath #OpenSource #MathSky
If you are checking out Cargo, I would also check out NPM (node package manager), which is one of the most popular javascript package managers.
No of course not! I would say the opposite; the fact that it is open source helps because you can actually understand what is happening, as long as you take the time to figure it out.
I was mostly just talking about understanding the code, not just the parameters. I agree that it is annoying that a lot of parameters are repeated.
I spent a lot of time figuring out that a '>' should be a '<'...
What prompted me to write the comment, however, is the amount of details that are involved. I doubt many users could successfully tune any solver without strong knowledge of its internals.
After attempting to tune MIR cuts in SCIP for 3.5 days, I understand better why people are willing to pay so much for a commercial MIP solver license.
🔄 Updated Arxiv Paper
Title: Sparsity-driven Aggregation of Mixed Integer Programs
Authors: Liding Xu, Gioni Mexi, Ksenia Bestuzheva
Read more: https://arxiv.org/abs/2502.01192
registration for the 2025 school on column generation is now open www.gerad.ca/colloques/Co... #orms
The bugfix release 9.2.1 of the SCIP Optimization Suite is now available.
This brings updates to GCG, PaPILO, SCIP, and SoPlex:
- github.com/scipopt/gcg/...
- github.com/scipopt/papi...
- github.com/scipopt/scip...
- github.com/scipopt/sopl...
#orms
