Dual variable of a constraint (python)

[Juan Zhang]

Hi,

I am trying to retrieve the value of the dual variable associated with a constraint. So far I have not been successful, Is the following syntax correct?

Output

[AMPL Google Group]

You can use <Constraint_name>.dual to get the dual values.

--
Paras Tiwari
am...@googlegroups.com

{#HS:584436544-8147#}

On Sun, May 20, 2018 at 4:04 PM UTC, Ampl Modeling Language <am...@googlegroups.com> wrote:

Hi,

I am trying to retrieve the value of the dual variable associated with a constraint. So far I have not been successful, Is the following syntax correct?

Output

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[AMPL Google Group]

The error "Wrong number of indices used" indicates that the constraint is indexed. For indexed constraints you can obtain the dual values as follows:

print ("Load_Balance1 = ", LoadCost1.getValues().toList())

or, alternatively:

print ("Load_Balance1 = ", LoadCost1.getValues().toDict())

--
Filipe Brandão
am...@googlegroups.com

{#HS:584436544-8147#}

On Sun, May 20, 2018 at 7:56 PM UTC, AMPL Google Group <am...@googlegroups.com> wrote:

You can use <Constraint_name>.dual to get the dual values.

--
Paras Tiwari
am...@googlegroups.com

On Sun, May 20, 2018 at 4:04 PM UTC, Ampl Modeling Language <am...@googlegroups.com> wrote:

Hi,

I am trying to retrieve the value of the dual variable associated with a constraint. So far I have not been successful, Is the following syntax correct?

Output