Do not reset custom zoom level when using slider in a slicer plot

[henrikjacobsenfys]

As mentioned on Slack, I sometimes use the zoom button in a slicer plot to focus on some detail. Often I want to see how this detail changes when using a slider. However, using the slider resets the zoom level. It would be neat if it didn't, or if there was a setting to turn it on/off.

[MridulS]

Hah, wasn't this the same issue #340? or am I missing something here?

[henrikjacobsenfys]

Hah, wasn't this the same issue #340? or am I missing something here?

Whoops, yes indeed. It's been so long since I made that issue that I forgot about it.

It would be neat if autoscale could be turned off only when zoomed in, but I don't know how difficult that would be.

[nvaytet]

Does autoscale=False not work for your purposes?
Only when zoomed in is going to be too tricky and lead to unexpected behavior.

There is the button to manually auto scale in the toolbar (the vertical arrows) which in combination with autoscale=False should work well in most cases?

[henrikjacobsenfys]

I had forgotten that I asked for this before, which is my bad. Sorry!

autoscale=False works quite well, except I'm also losing autoscale of the plot when it gets made. Here are two figures, the first is with autoscale=True, the second with autoscale=False

Clicking the autoscale button works, but it would be convenient to not have to tell users to click that button every time they make a slicer plot :)

[nvaytet]

So if I understand correctly, you would like to have the figure made as it is, but just call autoscale() once before we render the figure in the notebook. Would that be enough?

[henrikjacobsenfys]

Yes exactly :)

[nvaytet]

Am I right that your problem stems from the fact that you are using the autoscale=False arg, and using your custom function that 'clicks' the single slider handle button before returning the figure?

Because by default, the range slider will encompass all data and the autoscaling will fit to the data well.
If you use mode='single', you don't get the buttons to toggle between slider modes, but the scaling is once again fine.

So I would say the fix should lie in the function that you made? Something like

def my_slicer_plot(data, **kwargs):
    sl = pp.slicer(data, **kwargs)
    sl.slider.button.click()  # Note pseudo code
    sl.autoscale()
    sl.canvas.draw()
    return sl

[henrikjacobsenfys]

Nope, I'm not doing anything advanced, just calling plopp with a bunch of kwargs, then updating the slider to default to single like you showed me elsewhere (on slack?)

Perhaps this is what is happening? The figure is created, defaulting to summing all data (forgot the name, the left button near the slicer). Autoscale is called once. Then I change it to showing only a single index on the x axis (like mode='single', but keeping the option to toggle), and since autoscale=False, it doesn't scale the axes anymore.

Ideally, I'd have a second option like autoscale=True, autoscale_when_zoomed=False so that it's scaled when people go through the data normally, but also allows zooming in on a feature and watching how it depends on the coordinates.

Or perhaps another button to toggle autoscale? It can be on by default, and when zooming in, people can turn it off if they want, and it stays at the current axis limits. I'm just writing this as I think of it, but that last option might be closest to what I think users want :)

[nvaytet]

Then I change it to showing only a single index on the x axis (like mode='single', but keeping the option to toggle), and since autoscale=False, it doesn't scale the axes anymore.

This was what I had described above (I thought?):
"you are using the autoscale=False arg, and using your custom function that 'clicks' the single slider handle button before returning the figure?"

If you are changing to show a single handle, what prevents you from calling autoscale() and draw() right after that?

Or perhaps another button to toggle autoscale?

I don't want to add more buttons (I think we already have many), but I can show you how to add more if you want to make your own function.

[henrikjacobsenfys]

Sorry to be unclear, was on my phone and trying to give a fast answer, and also trying to figure out what's going on as I was typing :). Here's the code:

fig = pp.slicer(
    self.binned_data,
    **plot_kwargs_defaults,
)
for widget in fig.bottom_bar[0].controls.values():
    widget.slider_toggler.value = '-o-'

You're right, I can call autoscale() after this.

The more I think about it, the more I like the idea of a button to toggle autoscale. It's not top of my priority, but I'll come by and ask about it some time soon