# Plotting powers of 10 on the colorbar

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Mathan on 7 Apr 2022
Commented: Star Strider on 7 Apr 2022
Hello,
Is there any way to have powers of 10 (like 1e5, 1e6, 1e7) to be plotted on the colorbar as tickmarks without resorting to using log10? I tried the following code.
col = colorbar('XTickLabel', {'10^{5}', '10^{6}', '10^{7}'}, 'XTick',1e10:1e11:1e12);
caxis([1e10 1e12])
but that just gives me a colorbar with the xticks repeated as shown in colorbar.jpg (attached).
I also tried taking the log10 of these values as shown by the following code and got the desired output as shown in colorbar_log.jpg (attached):
col = colorbar('XTickLabel', {'10^{5}', '10^{6}', '10^{7}'}, 'XTick',log10(1e5):1:log10(1e7));
caxis([log10(1e5) log10(1e7)])
I however was wondering whether the same output as in colorbar_log.jpg can be obtained without resorting to taking log10.
Thanks.

Star Strider on 7 Apr 2022
These are 'Ruler' properties, and they are not in the colorbar documentation. (I had to go searching for them, and then experiment.)
Try this —
[X,Y] = meshgrid(-1000:10:1000);
Z = exp(-(X.^2+Y.^2)/1E5)*1E6;
figure
surf(X,Y,Z, 'EdgeColor','none')
grid on
colormap(turbo)
hcb = colorbar;
% get(hcb);
hcb.Ruler.Exponent = 3;
hcb.Ruler.Scale = 'log'; See NumericRuler Properties for more details.
.
Star Strider on 7 Apr 2022
As always, my pleasure!

### More Answers (1)

Voss on 7 Apr 2022
Edited: Voss on 7 Apr 2022
You can use naturlal log (log) or base-2 log (log2) (but I think log10 makes the most sense):
col = colorbar('XTickLabel', {'10^{5}', '10^{6}', '10^{7}'}, 'XTick',log(10.^(5:7))/log(10));
caxis([5 7]) figure();
col = colorbar('XTickLabel', {'10^{5}', '10^{6}', '10^{7}'}, 'XTick',log2(10.^(5:7))/log2(10));
caxis([5 7]) ##### 2 CommentsShowHide 1 older comment
Voss on 7 Apr 2022
Exactly. log10 with an extra log.