# Is this sort of a constraint implementable in Python?

V

#### varun7rs

Hello Everyone,

I'm working on a python code to input matrices into CPLEX solver. I have most 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 oneof the weirdest looking constraints which I don't know how to express in Python because python basically takes matrices and inputs them into cplex. My 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] = 1 ==> x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS[dns, w] + x_PoP[dns, w] >= 1
else x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS[dns, w] + x_PoP[dns, w] = 0;
Could you help me fix this problem?

Thank You

G

#### Gary Herron

Hello Everyone,

I'm working on a python code to input matrices into CPLEX solver. I have most 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 Python because python basically takes matrices and inputs them into cplex. My 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] = 1 ==> x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS[dns, w] + x_PoP[dns, w] >= 1
else x_SGW[dns, w] + x_PGW[dns, w] + x_MME[dns, w] + x_IMS[dns, w] + x_PoP[dns, w] = 0;
Could you help me fix this problem?

Thank You

This is more a CPLEX question than a Python question. (Or rather a