MATLAB: How to get a specified number of local maxima

curvedatafindpeaksMATLABmaximamaximumminimaminimumsignalsignal processingSignal Processing Toolboxtable

I have a signal and I only want the top two or three local maxima, I don't want the 5000 maxima that the findpeaks() function gives me. Is there a way to get this? Thanks.

Best Answer

You can use this function. I used this for taking top 2 frequency spectra maxima. You can find the min with the same logic.

**Update:Replace max(j) with val(j) in the function

Related Solutions

MATLAB: How to identify and get the average of local maximum negative peaks for a set of data

If you have R2017b, see if the islocalmin (link) function will do what you want.

If you have the Signal Processing Toolbox, another option is to use the findpeaks (link) function on your negated signal (turning minima into maxima). The locations will be correct and not require any transformation, the peak values returned will be the negative of the actual values.

Use the mean (link) function to get the average (arithmetic mean).

MATLAB: Is findpeaks same as local maxima

Let's have a look at the simple example from documentation of findpeaks:

data=[25 8 15 5 6 10 10 3 1 20 7];
findpeaks(data)

When you see the marked points on the plot, none of them are differentiable since there are more than one tangent line that can be drawn at those points. Therefore:

That the derivative must be a zero at that point? Is this also satisfied?

No, it is not, as you can see.

Best Answer

Related Solutions

MATLAB: How to identify and get the average of local maximum negative peaks for a set of data

MATLAB: Is findpeaks same as local maxima

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