[Cbc] some issues with LP file format

[Aditya Gandhi]

Folks,
We are using v 2.7.5 of the cbc.exe and passing it a .lp file to help solve the model.

While using this we identified few things to be careful of
1.      Using < or > in an equation in subject to leads to a crash. Using <= or >= works.
a.      i.e. A + B < 10 will not work
b.      A + B <= 10 will work
2.      When creating a constraint the format constraintName: constraintEquation the tool expects there to be no space between the constraint Name and the :
a.      i.e. const1: A + B <=10 will work
b.      const1 : A + B <= 10 will not work
3.      If the objective has two entries for the same variable then the last coefficient is used instead of
a.      i.e. in objective if I have 10 A - 3 A then only -3 A will be considered

we have modified our model generation to handle all these.

Question:
Are there other such know special handling that we need to be aware of while generating a .LP file?

Regards
Aditya


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