Experiment freezes in Pavlovia

My experiment is working fine offline, but online it starts and after the second screen it stops and I get the following error message:

Does anyone know what is happening?

Did you write code components in python for your offline version of the experiment and imported numpy as np?

If the answer is yes:
The error might arise from some kind of numpy function that you are calling by using np.function.
The import numpy as np part itself does not throw an error but as soon as you try to call a function that kind of ReferenceError appears.

As far as I know there is no package in java script that you can use instead of numpy.
Do you already know the Python to JavaScript Crib Sheet?

It’s pretty useful to get your offline experiment online!

Dear Kim-Laura,

Thank you for your email and response. I fixed this error, but now the experiment freezes in the initializing page. Do you know what kind of error this could be?
Thank you!

Kind regards,


Use my crib sheet to learn how to look at the console for the actual error.

Best wishes,