MATLAB: Area calculation within contour

areacontourisocontour

Sirs, I have the following plot

[C,h] = contour(X,Y,Z,[s,s])

Where s is a variable that I change. This plot the image:

I am interested to calculate the area inside this contour (so I can compare different values of s)

I have attempted to use some previous solutions I have found on this site, to no joy.

I have attached data for X,Y,Z

s can take any value <Z max

kind regards. W

Best Answer

I think I have a rather clumsy numeric answer.

I count the number of entries in Z that are equal or larger than s.

Then multiply by the area of a unit "pixel" (because I know the dimensions of X,Y I know how many "pixels" are in X,Y and so the area of that pixel).

Thanks for everybody's help W

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