Forum Discussion
Bug report: addVariable() has quadratic time complexity on QCQP's
Hi, I'm using the Python API of Xpress and I noticed that addVariable() has quadratic time complexity when the problem is a QCQP. This code here demonstrates the issue: import timeit
def create_...
Thanks for the reply!
Manually aggregating variables and constraints is very cumbersome, if the problem is complicated and distributed over dozens of source files (which it is in my case). Great if the addVariable function can be fixed to have constant-time overhead, so that aggregation is not that critical.
For the time being I will wrap the Xpress problem class and do the aggregation in the wrapper, so that I don't have to change all my existing code.
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