Forum Discussion
Storing python xp.constraint objects in numpy arrays or pandas Series
We would like to store a list of xpress xp.constraint objects in a pandas Series. We have found that the xp.constraint objects cannot be stored in numpy arrays or pandas Series. Here is example cod...
I cannot replicate that behavior, the code you submitted runs fine on two platforms: Mac (pandas 1.2.0 and numpy 1.19.5) and Linux (pandas 1.2.2 and numpy 1.20.1) using xpress 8.12. Can you provide more details on the pandas and numpy (and xpress) versions you are using?
Note that as of version 8.9 we introduced a dtype for numpy arrays of constraints, and it's called xpress.npconstraint. So the declaration of the numpy array should be
a = np.array(ctl, dtype=xp.npconstraint)This could then be added as a pandas series, which accepts numpy arrays.