setting significant no. of digits

[am610]

I am a bit confused on how to use the nice number or the significant digit function to reduce the useless number of trailing digits. It also hurts the plot. Attached figure shows this,

[mraveri]

Ah, good catch, this is a python3 problem with number to string conversion...
This is solved by converting to strings this way: str('{:g}'.format(number))

Will add it later!