Finding peaks with a set amplitude range?

2 次查看（过去 30 天）
HC98
HC98 2023-2-10
回答： Star Strider 2023-2-12
I'm findint the peaks in a signal wich have an amplitude between 0.2 and 1. Trouble is when I call findpeaks via
[pks,locs] = findpeaks(data(1, :),x); %,x);
logicalIndexes = (pks > 0.8) & (pks < 1);
It just returns a bunch of zeros even though I told it not to. Any ideas?

请先登录，再回答此问题。

回答（2 个）

Mathieu NOE
Mathieu NOE 2023-2-10
Ran in:
hello
see the demo code below :
n = 100;
x= 1:n;
y = rand(1,n);
[pks,locs] = findpeaks(y,x);
logicalIndexes = (pks > 0.8) & (pks < 1);
ind = locs(logicalIndexes);
plot(x,y,x(ind),y(ind),'dr');
  4 个评论
显示 2更早的评论
HC98
HC98 2023-2-10
How can I get the corresponding x value for the peaks?
Mathieu NOE
Mathieu NOE 2023-2-12
hello again
the x and y values of the peaks as shown above in my demo code are x(ind),y(ind)
n = 100;
x= 1:n;
y = rand(1,n);
[pks,locs] = findpeaks(y,x);
logicalIndexes = (pks > 0.8) & (pks < 1);
ind = locs(logicalIndexes);
plot(x,y,x(ind),y(ind),'dr');

请先登录，再进行评论。

Star Strider
Star Strider 2023-2-12
‘It just returns a bunch of zeros even though I told it not to. Any ideas?’
It may seem that a logical vector is returning zeros (false values, and there may be many zeros in it), however if you use:
NonZeroNr = nnz(logicalIndexes)
to find the number of true values, or:
NumericalIndices = find(logicalIndexes)
to return the subscript indices associated with the true values.
.

类别

在 Help Center 和 File Exchange 中查找有关 Descriptive Statistics 的更多信息

标签

产品


版本

R2022b

Community Treasure Hunt

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

Start Hunting!

Translated by