I know in Integer Optimization problem, we can use differenct solver(cp-sat or original-cp).In routing problem（tsp or other）how to use differenct solve problem. I find this function(SolveModelWithSat) maybe can use different solver by the ortools document,but I have no idea how to use it.
There are parameters that control what to use.
Please note that CP-SAT implementation does not support all features.
See: This section in the parameter file
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I've been fiddling for a bit with the fuse package with python3.
When trying to create a FUSE instance, I came across the nothreads argument.
Can anyone please elaborate on what this does?
I can guess that setting this flag to True the software no longer supports multithreading, but what I would like to know is how it changes the software's behaviour, what would the flow be with and without setting it to True?
Thanks
Torchscript provides torch.jit.trace and torch.jit.script to convert pytorch code from eager mode to script model. From the documentation, I can understand torch.jit.trace cannot handle control flows and other data structures present in the python. Hence torch.jit.script was developed to overcome the problems in torch.jit.trace.
But it looks like torch.jit.script works for all the cases, then why do we need torch.jit.trace?
Please help me understand the difference between these two methods
If torch.jit.script works for your code, then that's all you should need. Code that uses dynamic behavior such as polymorphism isn't supported by the compiler torch.jit.script uses, so for cases like that, you would need to use torch.jit.trace.
I am looking at a two step approach for a optimization problem. My first step is using a MILP formulation of the problem and the second step involves using the solution from the first step as an initial solution but now with a MIQP formulation. I have been able to apply this concept in MATLAB using CPLEX. However, I am now trying the same using CVXPY with CPLEX as the solver. Now I know about the warm_start option but this does not work with the CPLEX solver. I am able to set CPLEX parameters but I am not sure how to initialize my solution. I am thinking of setting the ADVANCE START SWITCH parameter for CPLEX to 1, but now I need to set the initial solution. According to this page: http://www-eio.upc.es/lceio/manuals/cplex-11/html/usrcplex/solveMIP17.html, I need to use the method setVectors in a Concert Technology application, or by using CPXcopymipstart in a Callable Library application to set the initial solution. I am unsure of how to use this along with CVXPY.
The functionality you are looking for does not currently exist in CVXPY. CVXPY is a generic modeling layer that wraps around several solvers and it does not expose the CPLEX-specific CPXreadcopymipstarts nor CPXaddmipstarts functionality.
The fact that setting the value property of variables and using the warm_start option, as suggested in this answer, doesn't work, is a CVXPY issue. It looks like there is an open github issue for this here. In the future, this will likely be the intended solution to your general question.
For now, you'll have to use one of the CPLEX APIs directly. As you mentioned in the comments of this related stackoverflow question, you do not like the idea of using the lower-level CPLEX Python API. That leaves you with docplex as a viable option.
Error: : (vlog-7027) Hierarchical reference not allowed from within a package.
Is there a system function which can be used to get past this? I know that that using an interface is the right way to read a signal.
What is the reason for not allowing hierarchical references in a package(apart from portability)?
The package construct is all about sharing and portability. The use of packages demands a strict compilation order dependency. Adding hierarchical references to a package breaks this ordering.
It most cases, using virtual interfaces is a solution to this issue. There are other suggestions in my DVCon paper. Of course, if you could share exactly what you are attempting to do, then I could direct you towards the best course of action.
I am developing a library and I need to add extra codes to some of my methods of my objects at run time. there are two points here. first of all, the program I wanted to add extra code, is written before by some body else, and I don't wanted to edit it. second, my work is very similar to adding aspect before calling a method.
After searching and reading on in internet, I found out many frameworks like aspectj, ASPECTWERKZ and etc. that could do this job, but for example the problem with aspectj(when using in spring context) is that it doesn't provide you any API to do your weaving at runtime.
I also found out there are some libraries like ASM and javassist and etc. but they are so general and hard to learn, and my job is more likely to aspects.
So what do you suggest? is there any good library out there? Am I wrong about above libraries i mentioned earlier? Please Help!
With AspectJ you can apply your aspects when classes are loaded at runtime. See Load-Time Weaving documentation. Alternatively, you don't have to change your old code and can apply aspects at compile time.