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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1 answer
Cplex Error: Adding trivial infeasible linear constraint
I want to solve an integer programming model with cplex python. I have this model:
a and h are matrixes with 0s and 1s. p is a set of numbers.
here is a part of my cplex code for this model:
p=[i for i in range…
Sana.Nz
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Dial A Ride Problem on Python using CPLEX
I try to program a Dial A Ride Problem based on Cordeau and Laporte model.
I simplified the model :
-Only one vehicle
-Start equal terminal
-Erased time constraints
I manage to have some results with docplex on python
But there is trouble... I can't…
StabiloHB
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The sub-optimal with docplex (cplex) when time limit is reached?
I am using Docplex (Cplex python version) with a maximization objective. I set the time limit, using
mdl.solve(TimeLimit=600).
It is possible that the model doesn't reach the optimal during this time, so i want to get the objective value…
user12484944
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How to initiate the interval variable bounds in docplex (python)?
I have the following OPL code and need to implement it in docplex (python), i'm newbie in that field...
using CP;
dvar interval I1 in 0..20;
dvar interval I2 in 0..20;
dvar interval I3 in 0..20;
dvar int over1;
dvar int start1;
dvar int…
user12484944
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1 answer
how to define an indicator constraint in docplex python API?
I want to model an integer programming example with docplex in python. for an indicator constraint I have this equation (X is a binary variable):
I wrote this code :
for i1,i2,i3 in P:
mdl.add_indicator_constraints(x[(i,j,k)] for i,j,k in ijk…
Sana.Nz
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How to convert/get the value of integer expression in cplex?
I am new to Cplex. I need to compute the overlap between several intervals at same time. For that, i compute the overlap_length between two intervals at a time, and i save the max and min of the start/end points.
For example, let's consider three…
user12484944
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trying to install docplex on python Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output
Collecting docplex
Using cached https://files.pythonhosted.org/packages/1c/06/de7833f2e70d51286611a2676f130f0978d2c16f65047cb965d0af579d08/docplex-2.12.182.tar.gz
ERROR: Command errored out with exit status 1:
command:…
Radek
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Minimize percentage of delays with Docplex
I have a pandas dataframe like this:
tail_n | flight_route | Percentage_delay
_______________________________
'N14125' | '(VB, MI)' | 0.1
| '(CC, SK)' | 0.5
| '(KF, KC)' | 0.3
'N351JB' | '(AZ,…
coelidonum
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Rectangle scheduler using CPLEX constraint programming
I need to schedule a set of rectangles in a big rectangle (named bin) using the constraint programming.
As I'm using CPLEX, i found out the square sched example (I'm in fact new to CPLEX and PPC). When I have adapted the example for rectangle case,…
user12484944
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0
votes
1 answer
How do I Implement "Continuous with Minimum or Nothing" Variables in DocPlex?
I have a 5-20 variables in my problems, and generally for 3-6 the allowable solution space is either continuous down to a minimum value or exactly zero. For example, in one problem the first variable (x0) can be either be between 250-1000 or it can…
rhaskett
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2 answers
DOcplexException: Expecting sequence of constraints, got: True at position 0
I am using docplex in google collab with python
For the following LP, the some of the decision variables are predetermined, and the LP needs to be solved for that. It's a sequencing problem and the sequence is a set of given values. The other…
user3916398
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How to define objective function of CVRP with 3d cost matrix using CPLEX Solver?
The following is an extract from https://medium.com/cmsa-algorithm-for-the-service-of-the-capacitated/using-cplex-and-python-for-finding-an-exact-solution-for-the-cvrp-ac789ee0d8c4, which of course, works fine when using a 2d cost…
rc97496
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1 answer
DOCPLEX disable Warning: constraint has already been posted
I'm running a DOCPLEX model using the python API and one of the constraints causes the following error to be thrown.:
My question is 1. what does this mean and 2. how do I disable the warning?
Warning: constraint has already been posted: _x4844 <->…
Sledge
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DOCPLEX: adding a constraint with sums two variables
I'm using the CPLEX solver in Python through DOCPLEX.
Among other constraints, I would like to state the following one:
cnrt_10 = {
(w, w1, j-1, j): opt_model.add_constraint(ct=opt_model.sum(X_var[p, w, c, j-1] for c in range(1,…
campioni
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CPLEX and Anaconda Python integration error on MacOS
I installed Anaconda 1.9.7, the Python version is 3.7.3. Then used
conda install -c ibmdecisionoptimization cplex
and
pip install cplex
However, I face this error:
No module named 'docplex'.
There is nothing on the net for solving this error…
Sean
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