There is an existing similar question here that I have tried but didn't give me what I need.
I have an image with 20 spectral bands. How do I compute the area under the spectral curve that is bounded by the x (wavelength), y (reflectance) and the curve itself?
img <- brick("sample.tif")
a <- as.array(img)
I was thinking of making an array of the values, then maybe from that I could compute the area as suggested here. However, I just do not know how to proceed, with the many columns of spectral bands I have.