what does [ 0 : training_data_len , : ] meant here
you need to select rows starting from zero till training_data_len and all the columns from your scaled_data.
what does, train_data = scaled_data[0:training_data_len  , : ] in python
does it mean from 0 to training data length and then up to end
I tried to use it on Jupiter notebook
it is a code from machine learning problem