ticklabel_format reset to default by ScalarFormatter

[gepcel]

Example:

I want to set ticklabel's as scilimits=(-3, 3) and useMathText=True.
This is what works:

plt.plot(1, 10000, 2, 20000, 'ro')
ax = plt.gca()
ax.yaxis.set_major_formatter(mpl.ticker.ScalarFormatter(useMathText=True))
ax.ticklabel_format(scilimits=(-3, 3))  # put after 'set_major_formatter', scilimits works
plt.show()

And this is what doesn't work, by switching two line.

plot(1, 10000, 2, 20000, 'ro')
ax = gca()
ax.ticklabel_format(scilimits=(-3, 3))   #put before 'set_major_formatter', scilimits doesn't work.
ax.yaxis.set_major_formatter(mpl.ticker.ScalarFormatter(useMathText=True))
plt.show()

Reason:

This is what I've find out, I'd like to help, but I don't know weather this should be fixed or how this can be fixed.
In the source code here, every time a ScalarFormatter class was called, those two values (formatter.scientific, and formatter.scilimits) was reset.

Something to mention:

1. In matplotlib, there are always many more better ways to one same thing. If anyone know some more elegant way of doing this, please let me know. And this way of setting scilimits and useMathText is what I've learned from this very good tutorial.
2. I've made a commented about this in Ticklabel format not preserved after editing plot limits #6276 . But I'm sure they are relevant or not, so I'm filling this issue here.

[efiring]

This behavior is fundamental; I don't think it is likely to change. ticklabel_format changes properties of the existing formatter, and yaxis.set_major_formatter connects a new formatter to the y axis. What would be possible is to expose more parameters such as scilimits as kwargs to the ScalarFormatter constructor; and/or to expose more of them (such as useMathText) in ticklabel_format.

[gepcel]

I think to expose useMathText in ticklabel_format would be a better idea. It looks more convenient to do like this:

ax.ticklabel_format(axis='x', scilimits=(-3,3), useMathText=True)

If you agree with this, maybe I can make some changes.

[tacaswell]

You can use get_major_formatter() and poke at it directly.

[gepcel]

Can anyone please examine this?
Thank you.

[gepcel]

Should I close this? I'm new to github.

[tacaswell]

No, it will automatically close when the pull request is merged.

[tacaswell]

Closed by #6337

@gepcel if you put closes #ISSUENUMBER in a git commit message that is what triggers the auto closing.