find peaks.

2 次查看（过去 30 天）
God'sSon
God'sSon 2011-5-23
hello, I have a plot of values from my fft function for a sinewave audio signal. I am now trying to analyze each peak in the plot to give me the sum of the peak and two other lower points on both sides of the peak. can anyone please help?
  1 个评论
God'sSon
God'sSon 2011-5-23
Hello,
This is the program I am trying to explain. After this is executed, how can I use the program to get the values of the peaks in the plot into my program?
N=2048;
fs=48000;
n=0:1:N-1;
F = fs*[0:N-1]/N;
w_a=sin((pi*(n'+0.5))/N);% calculate sine window
x1=w_a'.*sin(n*pi/24);
X1 = abs(fft(x1,N)).^2;
plot(F,X1)

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Laura Proctor
Laura Proctor 2011-5-23
Try FINDPEAKS:
[Xm Im] = findpeaks(X1)
Fm = F(Im)
The Fm and Xm values will hold your x and y values for the peaks.
  5 个评论
显示 3更早的评论
Laura Proctor
Laura Proctor 2011-5-24
Not quite...
[Xm Im] = findpeaks(X1)
iVals = reshape([ Im - 1 ; Im ; Im + 1],1,[])
xVals = F(iVals)
yVals = X1(iVals)
God'sSon
God'sSon 2011-5-24
this works perfectly. thank you very much.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Spectral Measurements 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