Remove NaN activeTime in create_reading_time_matrix_numpy()
Some log-entries contain activeTime == null despite having a documentId and a userId. create_reading_time_matrix_numpy() sets in this case the user-document cell in the matrix to 0.0 . I would expect in this cell 'nan', since we have no clue how "activeTime" == null endet up in the log set. I would ignore log-entries without a activeTime.
This branch removes log-entries without a activeTime