Debugger tool in GAMS - gams-math

I want to find my mistake in GAMS model. I don't have any errors , but my model doesn't work well
Is there any debugging tools in GAMS ?( like debugger tools in other software, e.g MATLAB)
Best

Unfortunately, I have not come across any.
If you have no errors in GAMS, it rather points to a modelling problem rather than a GAMS one. GAMS is like any other programming/modelling software, what you put in is what you get out. However, there are some commands and some intuitive ways you can find out the problem with your model:
One common way is by using the display and $stop commands. If you have loops within your GAMS code, it is best to track the progress of the loop by displaying some key variables either to your .lst file or using put utility (also a nice tool). I use the put utility, and write the code to display key variables at each point of my code to identify where things may have gone wrong.
The $stop command terminates your GAMS code at the line in which it is written.
Hope this helps.

Related

Is it possible to write a presolved problem into a file?

I would like to write a presolved problem into a file. Is there any way to do it?
write problem does not do it for me, it gives me the original problem that I read with SCIP.
The context is that I am working on SAT problems. The presolving phase of SCIP reduces the number of constraints and variables of the problem, effectively making the problem a little smaller. I would like to take a look at the presolved problem and compare it with the original problem and make some observations.
Yes, it is very easy, just use write transproblem.
The SCIP interactive shell also tells you all the possible commands that you can use, e.g. if you just type write in the SCIP shell, you see all available write commands

How to find the size of a reg in verilog?

I was wondering if there were a way to compute the size of a reg in Verilog. I researched it quite a bit, and found $size(a), but it's only in SystemVerilog, and it won't work in my verilog program.
Does anyone know an alternative for this??
I also wanted to ask as a side note; I'm having some trouble with my test bench in the sense that when I update a value in the file, that change is not taken in consideration when I simulate. I've been told I might have been using an old test bench but the one I am continuously simulating is the only one available in this project.
EDIT:
To give you an idea of what's the problem: in my code there is a "start" signal and when it is set to 1, the operation starts. Otherwise, it stays idle. I began writing the test bench with start=0, tested it and simulated it, then edited the test bench by setting start to 1. But when I simulate it, the start signal remains 0 in the waveform. I tried to check whether I was using another test bench, but it is the only test bench I am using in this project.
Given that I was on a deadline, I worked on the code so that it would adapt to the "frozen" test bench. I am getting now all the results I want, but I wanted to test some other features of my code, so I created a new project and copy pasted the code in new files (including the same test bench). But when I ran a simulation, the waveform displayed wrong results (even though I was using the exact same code in all modules and test bench). Any idea why?
Any help would be appreciated :)
There is a standardised way to do this, but it requires you to use the VPI, which I don't think you get on Modelsim's student edition. In short, you have to write C code, and dynamically link it to the simulator. In the C code, you can get object properties using routines such as vpi_get. Useful properites might be vpiSize, which is what you want, vpiLeftRange, vpiRightRange, and so on.
Having said all that, Verilog is essentially a static language, and objects have to be declared with a static width using constant expressions. Having a run-time method to determine an object's size is therefore of pretty limited value (since you should already know it), and may not solve whatever problem you actually have. Your question would make more sense for VHDL (and SystemVerilog?), which are much more dynamic.
Note on Icarus: the developers have pushed lots of SystemVerilog stuff back into the main language. If you take advantge of this you may find that your code is not portable.
Second part of your question: you need to be specific on what your problem actually is.

Modelica class diagrams

I am looking for a tool that can (automatically) create class diagrams like this one from Modelica code:
https://trac.modelica.org/Modelica/attachment/ticket/85/classDiagramModelicaMedia.png
I need to create a couple of such diagrams and an automated solution would help a lot!
So far, I found this article about Modelica CDV (class diagram viewer):
https://www.modelica.org/events/modelica2006/Proceedings/sessions/Session1c1.pdf
but not a ready to use tool. Any ideas?
This can be done with SystemModeler and Mathematica. The relevant function is a little bit hidden, but it's there. Here's an example:
WSMLink`Library`WSMDependencyGraph["Modelica.Mechanics.Rotational.Components.Spring"]
When hovering over the classes, the full name appears:
The object returned from the function includes a Graph, so you can operate on it with all the graph functionality in Mathematica. Also the function takes the same arguments as Graph, so you can get different graph layouts if needed.
I don't have any specific suggestions, but you might find that a tool like OpenModelica could extract and output sufficient information to construct such diagrams. It seems to have many command line switches for outputting lots of information (debugging and otherwise).

How to encourage positive developer behavior with an IDE?

The goal of IDEs is increase productivity. They do a great job at that. Refactoring, navigation, inline documentation, auto completion help increase productivity immensely.
But: Every tool is a weapon. The very same IDE helps to produce chunk code. Some IDE features are an invitation to produce bad code: code generation, code formatting tools, refactoring tools.
IDE overuse tends to isolate developers from the necessary details. It is a good thing that you can start working but at some point in your career you have to be able to figure out how to start a process. You can ignore this detail for some time, in the end they are important to write a working product (vs. bolted together stuff that works 90% of the time).
How do you encourage positive behavior of other developers working with an IDE? This is a question as old as copy and paste.
To get the right impression: developers have to have the maximum freedom to mobilize their maximum creativity and motivation. They may use IDEs and all the related tools as they see fit. Nobody should impose draconian measures on them. I don't want to demotivate and force someone to do something. Good behavior has to be encouraged. It has to itch little a bit if you do the wrong thing. In the same line as the SO "accept rate" metric (and reputation). You can ignore it but life is better if you follow the rules.
(The solution should work in a given setting. You can ignore reviews, changing the staffing or more education as potential solutions.)
Train your IDE, instead of being trained by it.
Set up code formatting the way you (or your team) wants it. Heck, even disable it in cases where it makes sense. I've never seen an IDE align something like this with a sensible combination of tabs and spaces (where \t is obviously the tab character):
{
\tcout << "Hello "
\t << (some + long + expression +
\t to_produce_the_word(world))
\t << endl;
}
In languages like Java, you cannot avoid boilerplate. The best option you have is to check generated code, ensuring that it is the same as what you'd have written by hand. Modify it as necessary. Configure your IDE to generate the exact code that you need, if possible. Eclipse is pretty good at this.
Know what's going on under the hood.
Know that your IDE is actually invoking the compiler. Have some insight into the flags that it passes. Be able to invoke the compiler from the command line.
Know about the runtime system. Be aware of the flags that are used or needed to launch your program. Be able to launch the program from a command line.
I think before anyone uses a RAD tool of any type they should be able to write the application from scratch (scratch being wiring together the framework components) in notepad potentially on a computer that is 10 years older than current technology :P. Not knowing the ins and outs of a paradigm/framework leads to bad code from novice developers who only learn things at a mile high view of the platforms they develop for. Perhaps they should do this in a few technologies -- i.e., GTK programming is completely different to MVC which is then also different to SWING and .NET.
I think the end result should be a developer that thinks of the finer details of a problem before they jump to thinking of how they will write an interface to it in a specific RAD environment.
its an open ended question, but...
We have a Eclipse format file that everyone shares, so that we all format the code in the same manor. (Except the one lone InteliJ guy we have).
Everyone shares a dictionary file. It helps to remove all the red lines from the code. Making it look cleaner and more readable.
I run EMMA over the code to find out who isn't testing their code, and then moan at them.
The main problems we face is that most of the team don't know all the features/power of the IDE (eclipse). The didn't know about CTRL + O (twice), or auto code gen. All I can do as a 'hot key wizard' is keep sharing my knowledge with them to help them become more productive.
I look forward to the day when my problem is that they auto gen as much as possible.
Rather than me finding bugs where the wrong value is returned from a getter method due to a typo.
Attempt development (at least occasionally) using only a text editor and launching the compilation, testing, etc. from the command line.
Typing the commands will get tedious very quickly so create scripts or (even better) learn rake, ant, msbuild.
If the IDE does code generation for you and that code generation is really important (such as generating classes from xsd or proxy classes from wsdl), try to find out how to run the code generation from the command line - then hook the code generation into a build (so you'll never be tempted to edit the generated code).
The idea of autoformatting code is great but it usually just turns your code into a mess. If you have less code, minor formatting inconsistencies are just not a big deal.
Adding code quality tools into your build - style checks, class and method sizes, complexity, code duplication, test coverage, etc (complexian, simian, flog, flay, ndepend, ncover, etc.) will discourage IDE generated code.

Print complete control flow through gdb including values of variables

The idea is that given a specific input to the program, somehow I want to automatically step-in through the complete program and dump its control flow along with all the data being used like classes and their variables. Is their a straightforward way to do this? Or can this be done by some scripting over gdb or does it require modification in gdb?
Ok the reason for this question is because of an idea regarding a debugging tool. What it does is this. Given two different inputs to a program, one causing an incorrect output and the other a correct one, it will tell what part of the control flow differ for them.
So What I think will be needed is a complete dump of these 2 control flows going into a diff engine. And if the two inputs are following similar control flows then their diff would (in many cases) give a good idea about why the bug exist.
This can be made into a very engaging tool with many features build on top of this.
Tell us a little more about the environment. dtrace, for example, will do a marvelous job of this in Solaris or Leopard. gprof is another possibility.
A bumpo version of this could be done with yes(1), or expect(1).
If you want to get fancy, GDB can be scripted with Python in some versions.
What you are describing sounds a bit like gdb's "tracepoint debugging".
See gdb's internal help "help tracepoint". You can also see a whitepaper
here: http://sourceware.org/gdb/talks/esc-west-1999/
Unfortunately, this functionality is not currently implemented for
native debugging, but I believe that CodeSourcery is doing some work
on it.
Check this out, unlike Coverity, Fenris is free and widly used..
How to print the next N executed lines automatically in GDB?