Units of kHz in frequency plots

When calling functions like pwelch, spectrogram or poctave with no function outputs, MATLAB conveniently provides a plot. That saves me from a lot of code (and potential bugs).

However, the following code (from poctave, I presume something similar occurs elsewhere) makes the plots less intuitive to my eyes, and often cause me to just define the plot from ground up.

% Determine engineering units
[~, scaleFactor, unitsStr] = signal.internal.utilities.getFrequencyEngUnits(CF(end));
...
elseif (value < 1000)
    scaleFactor = 1;
    unitsStr = 'Hz';
elseif (value < 1000 * 1000)
    scaleFactor = 1 / 1000;
    unitsStr = 'kHz';

I prefer the x-axis to read:

    [3,     8,    20,    50,   126,   316,   794,  1995,  5012, 12589] [Hz]

Rather than:

    [0.003,  0.008,  0.020,  0.050,  0.126,  0.316,  0.794,  1.995,  5.012, 12.589] [kHz]

I see that a similar question was asked here, where it is suggested to modify xticks after the fact, which is somewhat more complicated with the use of cathegorical for xticks:

https://se.mathworks.com/matlabcentral/answers/234862-how-can-i-change-the-scale-of-the-y-axis-unit-in-a-spectrogram

My request would be for a string option ala:

spectrogram(x, N, N/2, N, 48e3, 'Yaxis', 'UseSIBaseUnits')

Answer 1

[Giggs B.]

I know its late to answer, but for someone who faces the similar problem, try this:

set(gca,'XTick',[0.003, 0.008, 0.020, 0.050, 0.126, 0.316, 0.794, 1.995, 5.012, 12.589])
set(gca,'XTickLabel',[3, 8, 20, 50, 126, 316, 794, 1995, 5012, 12589])