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calculating integral for spectral signatures

2 messages · Robert J. Hijmans, Enrico Guastaldi

#
Enrico,

I think something like this should work for your purpose:

x <- c(1,2,3,5,7,12,13)
y <- c(1,2,9,11,7,20,10)

y1 <- y[-length(y)]
y2 <- y[-1]
dy <- y2 - y1
dx <- x[-1] - x[-length(x)]
dxy <- dx * (y1 + 0.5 * dy)
integral <- sum(dxy)

Robert