Activity for PyMathProg

Weihang Zhu posted a comment on discussion Help

Weihang Zhu — Fri, 21 Jun 2019 03:37:29 -0000

I am trying to work on a scheduling (task assignment) problem. My objective is to minimize the maximum makespan of the schedule. Could you please tell me how to define such an objective? Thank you,

Yingjie Lan posted a comment on discussion Help

Yingjie Lan — Sun, 30 Dec 2018 06:32:11 -0000

Since abs(x-y) <= 42 is not a linear function, this is not directly supported. However, you can get the same effect in PYMPROG with: -42 <= x-y <= 42 hope it helps, sorry for the late response.

Yingjie Lan posted a comment on discussion Help

Yingjie Lan — Sun, 30 Dec 2018 06:28:23 -0000

try the function/method vobj().

Sanjay posted a comment on discussion Help

Sanjay — Sat, 29 Dec 2018 04:59:53 -0000

I have wriiten a very basic code for an optimization problem. I am able to code for more complex problems too. But I am not finding out any source or example that shows how to get the value of the optimal solution. I tried using the sensitivity report. It gives the only the values of the variables but not the optimal solution value.

Marco posted a comment on discussion Help

Marco — Sun, 19 Aug 2018 14:47:07 -0000

Hello, I would like to use the absolute value in constraints and objective function. I believe that the absolute value can be desugared to plain linear constraints with shadow variables. Does PyMathProg support this feature? I have tried the following: model('foo') x = var('x') y = var('y') abs(x - y) < 42 which fails with: Traceback (most recent call last): File "", line 1, in TypeError: bad operand type for abs(): '_parex' Best, Marco

PyMathProg released /pymprog-1.0/pymprog-1.1.2.zip

PyMathProg — Thu, 08 Mar 2018 07:45:05 -0000

Yingjie Lan posted a comment on discussion Help

Yingjie Lan — Thu, 08 Mar 2018 07:32:51 -0000

Hi Julia, thanks for letting me know things worked out well in the end. And I will document it to help others out who might encounter similar problems, I suppose this is from really old version of pymprog. Best regards, Yingjie

PyMathProg released /v1.1.1/bug fix_ update bounds with parameters.tar.gz

PyMathProg — Tue, 23 Jan 2018 08:21:04 -0000

PyMathProg released /v1.1.1/bug fix_ update bounds with parameters.zip

PyMathProg — Tue, 23 Jan 2018 08:21:04 -0000

PyMathProg released /v1.1.1/README.md

PyMathProg — Tue, 23 Jan 2018 08:21:04 -0000

Julia Helmecke posted a comment on discussion Help

Julia Helmecke — Tue, 22 Aug 2017 12:30:14 -0000

Hallo Yingjie, I have solved the problem now. There was an issue in the first definition of the flux variable. I did not set both boundaries to None, so the default lower and upper bound was 0 and inf, respectively. This was not an issue in previous versions, so maybe you changed the default bounds in the var() function? If so, consider to include it in the "A word on compatability" section on your website. :) However, thank you for your help with my objective function issue. Now everything works...

Julia Helmecke posted a comment on discussion Help

Julia Helmecke — Tue, 22 Aug 2017 12:21:43 -0000

Hello Sebastian, I am using Pymprog with Python 2.7 and it works fine for me. How did you installed the module? Maybe you have just installed it in your Python3 package directory. Consider installing it with pip for Python2? Cheers, Julia

Sebastian Gonzato posted a comment on discussion Help

Sebastian Gonzato — Wed, 09 Aug 2017 14:11:24 -0000

I would like to incorporate the module pymprog in a Python 2.7 script, but it seems I can only get it to work if I use Python 3.4. For example, the command python practice.py gives me "ImportError: No module named pymprog" while python3 practice.py works fine. Am I missing something here, or does pymprog not work with Python 2.7?

Yingjie Lan posted a comment on discussion Help

Yingjie Lan — Mon, 12 Jun 2017 09:33:52 -0000

Hi Julia, Sorry again for the late response, I should check it more often seriously. The usual way to modify your objective coeficients is to use parameters, you may look at this example: http://pymprog.sourceforge.net/advanced.html#assign I tried the fva.py script, but it requres options to start running. Can you give me a commandline with options so that I can replicate the problem? Regards, Yingjie

Julia Helmecke posted a comment on discussion Help

Julia Helmecke — Sat, 29 Apr 2017 05:58:44 -0000

Hello Yingjie, thank you for your answer. Indeed, the program resets the objective value by giving an empty vector (all values are zero), since this was necessary in older pymprog versions. I have deleted this function and now the program runs without any error messages. The problem is, that it always returns an infeasible solution. Let me make it more clear: when I run the script for only one reaction of my model (the reaction is set as objective function), it works properly. But when I iterate...

PyMathProg released /v1.0.2/v1.0.2.tar.gz

PyMathProg — Mon, 10 Apr 2017 03:50:03 -0000

PyMathProg released /v1.0.2/v1.0.2.zip

PyMathProg — Mon, 10 Apr 2017 03:50:03 -0000

PyMathProg released /v1.0.2/README.md

PyMathProg — Mon, 10 Apr 2017 03:50:03 -0000

PyMathProg released /v1.0.1/maintenance release .tar.gz

PyMathProg — Fri, 31 Mar 2017 02:29:02 -0000

PyMathProg released /v1.0.1/README.md

PyMathProg — Fri, 31 Mar 2017 02:29:02 -0000

PyMathProg released /v1.0.1/maintenance release.zip

PyMathProg — Fri, 31 Mar 2017 02:29:02 -0000

Yingjie Lan posted a comment on discussion Help

Yingjie Lan — Tue, 28 Mar 2017 03:07:41 -0000

Hi Julia, Sorry for the late response, it seems that problem is caused by a bad objective...

Julia Helmecke modified a comment on discussion Help

Julia Helmecke — Wed, 15 Feb 2017 12:28:37 -0000

Hallo PyMathProg Team, first thanks for this awesome update! Unfortunately, I ran...

Julia Helmecke posted a comment on discussion Help

Julia Helmecke — Wed, 15 Feb 2017 12:28:00 -0000

Hallo PyMathProg Team, first thanks for this awesome update! Unfortunately, I ran...

PyMathProg released /README.rst

PyMathProg — Tue, 20 Dec 2016 11:28:02 -0000

Yingjie Lan committed [d29355]

Yingjie Lan — Wed, 14 Dec 2016 11:40:35 -0000

index.rst as quick guide

PyMathProg released /pymprog-1.0/README.rst

PyMathProg — Tue, 13 Dec 2016 01:35:02 -0000

PyMathProg released /pymprog-1.0/pymprog-1.0.0.zip

PyMathProg — Tue, 13 Dec 2016 01:20:02 -0000

Yingjie Lan committed [19e153]

Yingjie Lan — Mon, 12 Dec 2016 08:01:15 -0000

add doc uploading utility

PyMathProg released /pymprog-1.0/pymprog-1.0.0.zip

PyMathProg — Mon, 12 Dec 2016 07:20:03 -0000

Yingjie Lan committed [9921a4]

Yingjie Lan — Mon, 12 Dec 2016 07:17:44 -0000

admin shell scripts and polish-ups

Yingjie Lan committed [891757]

Yingjie Lan — Mon, 12 Dec 2016 03:38:16 -0000

Bug fix: linearize deleted variable

Yingjie Lan committed [da9dbb]

Yingjie Lan — Mon, 12 Dec 2016 03:29:45 -0000

Bug fix and examples for Python 2+3

Yingjie Lan committed [10d94f]

Yingjie Lan — Sun, 11 Dec 2016 14:26:26 -0000

Initial commit

PyMathProg released /OldFiles/pyglpk0.3.zip

PyMathProg — Thu, 08 Jan 2015 06:51:56 -0000

PyMathProg released /OldFiles/pymprog-0.1.0.zip

PyMathProg — Thu, 08 Jan 2015 06:51:56 -0000

PyMathProg released /OldFiles/pymprog-0.1.1.zip

PyMathProg — Thu, 08 Jan 2015 06:51:56 -0000

Allen posted a comment on discussion Help

Allen — Fri, 05 Sep 2014 14:27:15 -0000

I am trying to install pympl.4.2 on CentOS 6.5 (64-bit) for Python 2.7.5 I am recieving...

Jiravud Klongtrujrok posted a comment on discussion Help

Jiravud Klongtrujrok — Tue, 10 Jun 2014 13:16:04 -0000

Dear all, I'm trying to use PyMathProg for solving Bin Packing Problem the scripts...