Plot time of audio file in milliseconds

Hi there,

I have imported a .wav file into MATLAB, I am plotting this audio file in amplitude/time but I need it to be displayed in milliseconds rather than seconds.

The .wav file is configured in the workspace as data and fs.

The code I am using to plot the file in time is :

>> t=[0:length(data)-1] / fs;

>> plot(t, data);

Many thanks in advance for your time.

Answer 1

[Star Strider]

Try this:

plot(t*1E+3, data);

That converts seconds to milliseconds. The plot otherwise remains the same.

[Chris79]

That's great..thanks for such a quick response.

Is there any chance you could also please tell me how to stop the x-axis displaying every value in exponential (10^) form?

For example I would like 10,000 20,000.

I tried ax.XAxis.Exponent = 0 ..but it was unsuccessful.

[Star Strider]

As always, my pleasure.

To the best of my knowledge, there is no way to directly change the tick label format. However it is relatively straightforward to create your own tick labels:

xt = get(gca, 'XTick');
xtlbl = regexp(sprintf('%.0f\n', xt), '\n', 'split');
set(gca, 'XTick',xt, 'XTickLabel',xtlbl(1:end-1), 'FontSize',6)

The idea here is to get the tick label values, use sprintf to create your own label format, convert it to a cell array (in the regexp call here), then specify the tick positions with the tick labels so MATLAB knows where to put them. I added a 'FontSize' argument to make the tick labels more readable, although it is not necessary for the rest of the code.

[Chris79]

Again this is great and really useful.

Thank-you for sharing your knowledge and for explaining it too, it is much appreciated.

[Star Strider]

Thank you.

As always, my pleasure!