weak_portfolio.ipynb: weak portfolio always having 1/n weights

[mpugna]

Running the notebook iin Colab the weak long-only portfolio 's weights are always equal to 0.25 (i.e. the weka portfolio is equivalent fo the equal weighted portfolio). In the original example this was not true

[microprediction]

Thanks I realized what happenned and I think there is a fix done.

[microprediction]

i.e. updating should fix it but LMK if not