Suggest unexisting filename when saving displayed figure

[strazdas]

Wanted feature Automatically update the suggested filename to save a figure to if a file with the default filename already exists.

Situation now The default interface always suggests figure_1.png filename even when it exists. This means that, each time I want to save a figure, I have to check how many figures I have and update the filename to figure_<number_of_figures+1>.png.

It would be great if It was possible to specify the filename pattern in matplotlibrc file.

@strazdas @tacaswell How do you recommend specifying the pattern?
Currently I have a fix (that I'd like to get a PR in for at some point) that adopts the standard pattern when a filename exists. For example, if the window title of your figure is "Figure 1", then repeated saves would yield:

"figure_1.png", "figure_1 (1).png", "figure_1 (2).png" and etc.

If you wanted to specify the pattern, the only way I could see is specifying a boolean control for whether to inject a space between the number and title name, and which character you'd like to use as the brackets.

[efiring]

If you turn this into a PR, please don't try to put a space in the file name. Use another underscore, or a dash, or a dot.

@efiring Thanks for the response. With underscores, we'd have
"figure_1.png", "figure_1_1.png", "figure_1_2.png", "figure_1_3.png" and etc.

How would you like to have it with dash or dots? Before or after the file's extension?

For example "figure_1-2.png" or "figure_1.png-2"; "figure_1.2.png" or "figure_1.png.2".

[efiring]

"figure_1-2.png" would work fine. One doesn't want to interfere with the extension, since so many programs use it to decide what to do with a file.

[efiring]

Also, the dash is probably better than a dot; some programs stupidly treat everything after the first dot as the extension. I am not aware of anything that would cause problems with a dash.

Agreed! I will adjust the fix accordingly and aim to make a PR soon.

[umairidris]

Sorry @stallone1993! I already had this feature completed. Please see #4221. I would appreciate your feedback.

@umairidris - thanks for the heads up. My fix is pretty similar to yours (though I had it completed earlier on in the day - just wanted to make sure I was solving it in the preferred way). Cheers!