comment #1:

> Since it's not possible to display a colormap axis with infinite limits (and the figure seems to change to black when setting caxis([-inf inf]) indicating something is off, what is your expectation when setting it to those values?

I think I was half expecting that in analogy to xlim([-Inf,Inf]) caxis([-Inf,Inf]) would result in automatic axis setting.

testing in matlab 2024a:

>> clf;
colormap('default');
[x,y,z] = peaks(50);
contourf(x,y,z, -7:9);
caxis([-Inf,Inf]);
>> caxis

ans =

  -Inf   Inf

(so it seems caxis wasn't removed internally.)

it accepts [-inf, inf], and the image just has a slightly shifted but seemingly normal color range, and the axes property for clim is set to "CLim: [-Inf Inf]"

so it seems it should accept Infs for clim.  the question is maybe more how Octave should handle that .

i missed this part of the caxis help:

Data values outside this range are clamped to the first and last colormap entries.

checking compatibility, it seems in 2022 matlab removed caxis (well, renamed it clim. the function seems nearly identical).  Octave doesn't have a clim function. Could make a simple wrapper to add that compatibility.

from some older docs online:
"caxis([cmin cmax]) sets the color limits to specified minimum and maximum values. Data values less than cmin or greater than cmax map to cmin and cmax, respectively. Values between cmin and cmax linearly map to the current colormap."

so it seems caxis is just failing to perform this clamping operation.  i see that it's not just limited to inf:

>> size(colormap)
ans =

   64    3
>> caxis([-100, 9999999])
>> caxis
ans =

  -1.0000e+02   1.0000e+07

seems like those values should get clamped to something within bounds, and that number would get passed to colorbar.

I can confirm the bug(s). It doesn't look like the underlying clim property supports the inf value as a placeholder for "auto limits" as xlim property does. E.g. in the following example

clf
peaks (20)
get (gca, "xlim") ## -> [-3 3]
set (gca, "xlim", [-1 1])
get (gca, "xlim") ## -> [-1 1]
set (gca, "xlim", [-inf inf])
get (gca, "xlim") ## -> [-3 3]

get (gca, "clim") ## -> [-6.3605   7.5561]
set (gca, "clim", [-1 1])
get (gca, "clim") ## -> [-1 1]
set (gca, "clim", [-inf inf])
get (gca, "clim") ## -> [-inf inf]

We can see that instead of being replaced by and appropriate upper and lower color limit, the +/-inf values are stored. The first consequence is that the lines are all black, which is not expected for me (actually I don't know what I would expect for the middle between -inf and inf:-). Then only comes the second consequence with colorbar blindly using inf clim values for its computations. But note that if the underlying clim property was fixed, colorbar would work as well.

The following script:

clf;
colormap('default');
[x,y,z] = peaks(50);
contourf(x,y,z, -7:9);
caxis([-Inf,Inf]);
h = colorbar;

produces a plot looking as expected in matlab, results in an out-of-memory error with octave:

error: out of memory or dimension too large for Octave's index type
error: called from
    colorbar at line 321 column 12
    bug_cb at line 6 column 3

version:

9.1.91 (hg id: 97b44c6e3e35)