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Date: Tue, 10 Jun 2014 02:12:38 -0700 (PDT)
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Subject: Is this sort of a constraint implementable in Python?
From: varun7rs@gmail.com
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Xref: csiph.com comp.lang.python:73079

Hello Everyone,

I'm working on a python code to input matrices into CPLEX solver. I have mo=
st of my code running fine but as of now, I don't know how to express this =
constraint. My objective is to minimize the number of nodes. I have got one=
 of the weirdest looking constraints which I don't know how to express in P=
ython because python basically takes matrices and inputs them into cplex. M=
y constraint is as below. This was what I wrote in AMPL

minimize phy_nodes: sum {w in PHY_NODES} x_ns[w] ;

s.t. Phy_nodes_Eq{w in PHY_NODES, dns in DEMAND}:
x_ns[w] =3D 1 =3D=3D> x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS=
[dns, w] + x_PoP[dns, w] >=3D 1
else x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS[dns, w] + x_PoP[=
dns, w] =3D 0;
Could you help me fix this problem?=20

Thank You