GurobiError: Unsupported type (<class 'list'>) for LinExpr addition argument

Answered

Bo Lan

• April 24, 2019 02:49

Hi,

I run 'diet2.py' in Anaconda 4.2.0, Python 3.5.6 and met this problem.

 

Python 3.5.6 |Anaconda 4.2.0 (64-bit)| (default, Aug 26 2018, 16:05:27) [MSC v.1900 64 bit (AMD64)]

Type "copyright", "credits" or "license" for more information.

 

IPython 6.2.1 -- An enhanced Interactive Python.

 

runfile('D:/Program Files/gurobi751/win64/examples/python/diet2.py', wdir='D:/Program Files/gurobi751/win64/examples/python')

Traceback (most recent call last):

 

  File "<ipython-input-1-2ae817e615ea>", line 1, in <module>

    runfile('D:/Program Files/gurobi751/win64/examples/python/diet2.py', wdir='D:/Program Files/gurobi751/win64/examples/python')

 

  File "D:\Program Files\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 678, in runfile

    execfile(filename, namespace)

 

  File "D:\Program Files\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 106, in execfile

    exec(compile(f.read(), filename, 'exec'), namespace)

 

  File "D:/Program Files/gurobi751/win64/examples/python/diet2.py", line 72, in <module>

    foods, cost, nutritionValues)

 

  File "D:\Program Files\gurobi751\win64\examples\python\dietmodel.py", line 29, in solve

    for c in categories), "_")

 

  File "model.pxi", line 2552, in gurobipy.Model.addConstrs (../../src/python/gurobipy.c:78637)

 

  File "model.pxi", line 2464, in gurobipy.Model.addConstr (../../src/python/gurobipy.c:77389)

 

  File "linexpr.pxi", line 429, in gurobipy.LinExpr.__sub__ (../../src/python/gurobipy.c:32252)

 

  File "linexpr.pxi", line 408, in gurobipy.LinExpr.__add__ (../../src/python/gurobipy.c:31857)

 

  File "linexpr.pxi", line 153, in gurobipy.LinExpr.add (../../src/python/gurobipy.c:29245)

 

GurobiError: Unsupported type (<class 'list'>) for LinExpr addition argument

 

I had no idea.  A Gurobi provided example should not have a problem like this. Can anyone help me?

 

Thanks,

Larry

0

• Official comment

  

  Simranjit Kaur

  Gurobi Staff

  • December 06, 2024 00:59

  This post is more than three years old. Some information may not be up to date. For current information, please check the Gurobi Documentation or Knowledge Base. If you need more help, please create a new post in the community forum. Or why not try our AI Gurobot?.
• 

  Greg Glockner

  Gurobi Staff

  • April 24, 2019 16:46

  Gurobi Optimizer 7.5 is not compatible with Python 3.5. Can you try again with Python 3.6?

  0

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