How can I force the time-axis unit of spectrogram to be 'second(s)' ?

15 次查看（过去 30 天）
zhehao.nkd
zhehao.nkd 2021-5-25
评论： zhehao.nkd 2021-5-31
When I use the spectrogram function (https://www.mathworks.com/help/signal/ref/spectrogram.html) , I find that depends on the time duration of the y data, the time-axis units are dynamic, shifting between 'second(s)' and 'milisecond(s)'. So is it possible to force the unit to be 'second(s)'?
  2 个评论
Adam Danz
Adam Danz 2021-5-25
Are you referring to your inputs or are you referring to something in the plot produced by spectrogram?
It would be helpful to provide a screen shot of the figure or supply the input data, depending on what you're describing.
zhehao.nkd
zhehao.nkd 2021-5-26
Sorry for my vague description. I am referring to the plot generated by function spectrogram without defining the output.
For example,
fs = 32000;
y1 = wgn(1*fs,1,1);
y2 = wgn(2*fs,1,1);
figure;
subplot(2,1,1)
spectrogram(y1,hamming(512),512-round(fs/1e3),512,fs,'yaxis');
subplot(2,1,2)
spectrogram(y2,hamming(512),512-round(fs/1e3),512,fs,'yaxis');
This two subplots will have different time units as ms and s. So how can I force the unit to be s?

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Adam Danz
Adam Danz 2021-5-26
编辑：Adam Danz 2021-5-27
Ran in:
I don't know whether there's an input to spectrogram that could solve this but here's how to fix the labels after the plots are created.
You could detect whether the x-axis is in seconds or ms by the xlabel;
if strcmpi(ax1.XLabel.String, 'Time (ms)')
ax1.XTickLabels = compose('%.1f',ax1.XTick/1000); % set tick labels
xlabel(ax1, 'Time (s)') % set axis label
end
P1=[10,-1];
fs = 32000;
y1 = wgn(1*fs,1,1);
y2 = wgn(2*fs,1,1);
figure;
ax1 = subplot(2,1,1); % get handle
spectrogram(y1,hamming(512),512-round(fs/1e3),512,fs,'yaxis');
subplot(2,1,2)
spectrogram(y2,hamming(512),512-round(fs/1e3),512,fs,'yaxis');
ax1.XTickLabels = compose('%.1f',ax1.XTick/1000); % set tick labels
xlabel(ax1, 'Time (s)') % set axis label

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Axis Labels 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by