calculate FWHM and area of multiple peak

Hi, I have a graph that contains multiple peaks, I want to calculate the area of the peak and FWHM of each peak. I want to use the formula, Area = Height * FWHM.

In Matlab is there any default function to calculate FWHM and area. The curves are magnitude diagrams in the log scale. If I plot in linear scale the power of peak is near to zero. When I use the function to find peaks

[pks,locs,widths,proms] = findpeaks(x,y);

it gives 1×0 empty double row vector. Is it right way to calculate area from log scale graph? Any suggestions from anyone. Thank in advance.

Answer 1

[Star Strider]

‘... it gives 1×0 empty double row vector.’

That is most likely because the dependent variable vector (is this ‘y’ in your code?) must be the first argument to findpeaks (link).

Try this instead:

[pks,locs,widths,proms] = findpeaks(y,x);

or preferably, just return the indices of the peaks in the ‘locs’ output with:

[pks,locs,widths,proms] = findpeaks(y);

I find the indices easier to work with.

[Namira]

Thanks.

[Star Strider]

As always, my pleasure.