modestga zero division error about modest-py HOT 2 CLOSED

An observation:

The error comes from the estimation method parameter est in the simple_1param.py:

est represents a single unknown (C) and therefore contains a single-key dict with a 1D list value <= est.json. Correspondingly, the variable b (=list of tuples of length est) of the MODESTGA object (ga_parallel.py, line 305) becomes a list of single tuple element and is passed as parameter bounds to the method minimize defined in ga.py

Therefore, len(bounds) => (len(bounds) = 1) => 1-1/len(bounds) => division by zero in line 199 of ga.py

Keeping two variables unknown (C and R1) instead of one in simple_1param.py leads to the list of bounds containing two elements => 1 - 1/len(bounds) = 1 - 1/2 = 0.5 which "fixes" the problem (optimizer finishes with no error message).

Therefore, to enable estimation of a single unknown parameter in ModestPy, it seems appropriate to replace len(bounds) by len(bounds)+0.01 in the denominator or something else of this sort. Optimizer finishes with no error message.

from modest-py.

Thanks for tracking down the error. I fixed it in modestga: krzysztofarendt/modestga@24f69e6

You need to update the package: pip install -U modestga

from modest-py.