[python] ConvergenceWarning: Liblinear failed to converge, increase the number of iterations

Running the code of linear binary pattern for Adrian. This program runs but gives the following warning:

C:\Python27\lib\site-packages\sklearn\svm\base.py:922: ConvergenceWarning: Liblinear failed to converge, increase the number of iterations.
 "the number of iterations.", ConvergenceWarning

I am running python2.7 with opencv3.7, what should I do?

This question is related to python opencv lbph-algorithm

The answer is


Explicitly specifying the max_iter resolves the warning as the default max_iter is 100. [For Logistic Regression].

 logreg = LogisticRegression(max_iter=1000)

I reached the point that I set, up to max_iter=1200000 on my LinearSVC classifier, but still the "ConvergenceWarning" was still present. I fix the issue by just setting dual=False and leaving max_iter to its default.

With LogisticRegression(solver='lbfgs') classifier, you should increase max_iter. Mine have reached max_iter=7600 before the "ConvergenceWarning" disappears when training with large dataset's features.


Please incre max_iter to 10000 as default value is 1000. Possibly, increasing no. of iterations will help algorithm to converge. For me it converged and solver was -'lbfgs'

log_reg = LogisticRegression(solver='lbfgs',class_weight='balanced', max_iter=10000)