BUG: changed np.round(mean_diff,2) -> mean_diff:.2g to avoid trailing …

[jeswcollins]

…digits bug that appears in matplotlib figure output

• closes #xxxx
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[bashtage]

Need to ensure that the format doesn't change the value returned, but only prevents things like 1.23000000000001 from appearing.

[bashtage]

I think you need to round first and then apply the format string, since I'm not sure the format string actually rounds - I think it might truncate,

 f"{4.229:0.2g}"
Out[2]: '4.2'

In [3]: f"{4.229:0.2g}"
Out[3]: '4.2'

In [5]: import numpy as np

In [6]: f"{np.round(4.229,2)}"
Out[6]: '4.23'

See how these are different. You should ensure that they are the same. I think the format should also be .3g ,

In [12]: f"{np.round(4.209,2)}"
Out[12]: '4.21'

In [13]: f"{np.round(4.209,2):.2g}"
Out[13]: '4.2'

In [14]: f"{np.round(4.209,2):.3g}"
Out[14]: '4.21'