docplex (a.k.a. IBM® Decision Optimization CPLEX® Modeling for Python) is a Python modeling API that provides modules for mathematical programming via CPLEX and constraint programming via CP Optimizer.
Questions tagged [docplex]
316 questions
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Summatory with variables that have two indexes in PYTHON
I am trying to write something like this (which is a part of a constraint):
sum(a in ArcsOut[p.o]) F[a][p] for all p=(o,d) in pairs.
My code is :
I have a set of nodes:
nodes = ["uno","dos","tres","cuatro","cinco","seis"]
and its set of all…
Tive Surrender
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- 8
0
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1 answer
Summatory with Python and how associate sets with vectors
I have a set of nodes:
nodes = ["uno","dos","tres","cuatro","cinco","seis"]
and its set of all possible pairs
pairs = [(i,j) for i in nodes for j in nodes if i!=j]
Also, I have a vector of this set of pairs
d = [9, 26, 19, 13, 12, 11, 14, 26, 7,…
Tive Surrender
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0
votes
2 answers
Multidimensional decision variable python docplex
To solve my inventory problem I need a three-dimensional decision variable x_{ij}^t
I am new to the CPLEX Python API docplex and all I found so far is
m = Model(name='inventory_problem')
x = m.integer_var_matrix(keys1=all_origins,…
steph
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0 answers
How to find all available paths in a graph, not just the shortest ones?
I need to find all positive paths in a graph, but the shortest path algorithm only finds 1 best path. So I have to update the matrix and solve the model again. Is there any way to display all paths when path value is greater than 0.
I will also…
Alex
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-1
votes
1 answer
Python cplex: How do I get the absolute value of a linear expression in an optimization model?
I have a minimize problem and its objective function need to get absolute of a linear equation. But when I run these code, it raise this error TypeError: bad operand type for abs(): 'LinearExpr'. How can I fix this?
I searched this error on Internet…
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votes
1 answer
Creating and/or logic between constraints DOcplex python
I'm trying to transfer my constraints from Cplex OPT studio to the DOcplex Python.
The logic between the constraints is - if 1 of them does not met all the decision variables needs to be 0.
In Cplex Studio its look like that:
forall(r in risk_list)…
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1 answer
Can not solve Assignment Problem Using ILOG CPLEX Optimizer
The Assignment problem is from Google OR-Tools
Others framework can solve this problem, even using Excel Solver. But ILOG CPLEX cannot solve this problem.
Here is my code in jupyter notebook:
import cplex
import docplex.mp
from docplex.mp.model…
simon leung
- 61
- 3
-1
votes
1 answer
Cplex Python Gaps
How can I print the gaps(each iteration) like OPL's engine in Python? I want to keep the gaps like this:
Nodes Cuts/
Node Left Objective IInf Best Integer Best Bound ItCnt Gap
0…
Tunahan Bilgiç
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votes
1 answer
Why do i get no attribute in docplex?
I am running an optimization code in docplex but for some reason I get an error:
AttributeError: 'NoneType' object has no attribute 'get_value_dict'
This error refers to the line:
prod_hpp_grid_ts =…
Artur Zebrowski
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-1
votes
1 answer
How can I take the solution values from first calculation and use it in another calculation in python using docplex
I calculated a machine scheduling problem using docplex in python. I obtained one of the decision variable as:
yib
solution
y_0_1
1
y_1_2
1
y_2_1
1
y_3_1
1
y_4_1
1
Since I wanted to use this values in another calculation I used…
Melissa
- 9
- 3
-1
votes
1 answer
docplex issue: TypeError: Cannot use == to test expression equality, try using Python is operator or method equals:
mymodel = Model("OPL_Purchasing_plan");
nr_month= range(0, 12)
na_pur_req = [550, 750, 6500, 675, 210, 120, 0, 560, 140, 320, 0, 100]
na_average_cost = 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5, 12.5]
for i in nr_month:
…
suresh_chinthy
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votes
1 answer
Is CPlex Optimization Studio 12.9.0 compatible with Python notebooks for APIs. If yes, which version of Python?
I have installed Cplex (Optimization Studio 12.9.0 - Community Edition) and need to write Python APIs in it.
After installing setup.py as per…
ShraddhaBG
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votes
1 answer
Duplicate variable name warning in Python
I have developed a code for an optimization problem in Python and defined a binary variable in the model. Then I used the Docplex module to solve the model through the Cplex engine. I've mentioned a part of the code as follows.
from docplex.mp.model…
Nasser Tarin
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-2
votes
1 answer
Can someone fix my python code & docplex?
I have to do a python code for a project but when i run it, i have a problem with it. I try to fix it but it's always the same problem. It said the same code error...
this is my code
from docplex.mp.model import…
Theo GUIRROU
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-2
votes
1 answer
cpleqp equivalent in docplex
We can use cplexqp command to find the minimum of a problem using Cplex in matlab. I am looking for an alternative in docplex.
Cplex vs Docplex
user3702045
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