The DataDemo.py test program crashes

[twillis449]

The np.concatinate function calls in lines 80 and 85 fail because the axis indicator is set to 1 instead of 0. Just delete the final '1' parameter and things work.

[heliophagus]

Thanks for your note, twillis449! Your fix works well. Saved a lot of head-scratching. Not sure why demo() includes code that crashes from the get-go...!