Hi I’m plotting multiple colorbars side-by-side with different widths, and having trouble where the annotation size seems to scale with the colorbar width. I’ve done a lot of googling and a lot of trial and error and can’t seem to get the annotation sizes consistent. Below is an example: import py…

Thanks for the directing me to those discussions. I see that the scaling factor is a square root of the cbar width/15. With that information, I’m able to apply the rescaling factor to the original code and have the colorbar in it’s true measurements. Code below (sorry it’s a bit messy): import nump…

Hello @JonathonLeonard , are you using PyGMT with GMT 6.5.0? Up on GMT 6.5.0 the front sizes of labels and annotations of a colorbar are scaled relatively the the length of the colorbar. You can modify the GMT defaults locally to adjust the font size manually. For a general example please see How t…

Hi Yvonne, I think GMT’s autoscaling is still applied on top of what is specified using with pygmt.config(...). Result is that fonts of a longer scalebar are always bigger than of a shorter one. Please see some spaghetti code and plots below. import pygmt FONT_SIZES=['20p','10p','5p'] for FONT_…

Yes, autoscaling still applies if you manually adjust the font size. As mentioned in How to set font size on scale bar? · Issue #3230 · GenericMappingTools/pygmt · GitHub , it does not seem to be possible to set a fixed font size directly anymore (or I have not figured out how to do this now / in GMT…

[image] yvonnefroehlich: I feel one has to set a smaller font size locally only for the longer scale bar in order to end up with the same font size as for the shorter scale bar (or vice versa). Thanks for the answer. The same seems true for the color scales’ frame pen size, tick length/ pen …

If you set GMT_THEME=classic even in a modern mode session, you should be able to set exactly the font sizes (not tested).

Hm, yes, it seems like these parameters are also set relatively to the length of the colorbar in GMT 6.5.0.

Thanks @Joaquim for this suggestion! I just tested this in a simple code example. However, it looks like that the auotscaling still applies. import pygmt size = 5 region = [-size, size, -size, size] projection = "X10c/5c" frame = 0 position_long = "jBC+w8c/0.3c+h" position_short = "jTC+w3c/0.3c+…

So, in a modern session, it seems we can change the starting point (initial font sizes, tick …) but not the fact that it auto scales.

Thanks all for the help. So it seems the autoscaling is a feature/bug of gmt 6.5.0, and can’t be switched off. With inspiration from @yvonnefroehlich ’s comment, I’ve manually made a figure that looks consistent by manually adjusting the font size, tick lengths and offsets (below). I suppose another…

Multiple colorbars changes the annotation fontsize

Q&A PyGMT Q&A

Joaquim June 4, 2024, 12:37am 14

Lots of food for reading here (and links).

PyGMT uses only modern mode.

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Multiple colorbars changes the annotation fontsize

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