[R-sig-Geo] Comparing 2 rasterbricks using functions from TSdist package

[Bede-Fazekas Ákos]

Dear Jackson,

I think this is what you are searching for:
new_s3 <- setValues(r, sapply(1:ncell(r), function(i) 
fun(as.vector(s[i]), as.vector(s2[i]))))
plot(new_s3, colNA = "red")

HTH,
Ákos Bede-Fazekas
Hungarian Academy of Sciences



2020.05.28. 0:18 keltezéssel, Jackson Rodrigues írta:
> Dear all,
>
> Few days ago I got a important help from this list and I am really thankful
> for that.
> Today I have a similar challenge with 2 rasterbrick files.
>
> I would like to compare 2 rasterbricks using any similarity function (let's
> take CorDistance) from package TSdist.
> In my real data, both rasterbricks came from the same region but using
> different measurement techniques.
>
> I am trying to adapt the suggestion I got from here rather than looping on
> each cell, but no matter what I try I always get an error related to NA.
> It seems to be very simples but I am stuck since last Monday.
>
> I have played with several conditional ("ifelse", "if", "if else" etc) and
> logical tests ("|", "||", "&" etc) but I got nothing so far.
>
> Could someone help me and show me a path to go through?
> Below there is the cleanest code I have tried.
>
> Best regards
>
> Jackson
>
> ##############
> library(raster)
> library(TSdist)
>
> set.seed(12)
> r <- raster(nrow=10, ncol=10)
> s <- lapply(1:200, function(i) setValues(r, rnorm(ncell(r),
>                                                    sample.int(5,1), 0.5)))
> s <- stack(s)
> s[s < 0] <- NA
> s2<-s^2
>
> # Visualize that some pixels have NAs and other don't
> hasna <- stackApply(s, indices = 1, fun = function(x, na.rm){anyNA(x)})
> hasna2 <- stackApply(s2, indices = 1, fun = function(x, na.rm){anyNA(x)})
>
> par(mfrow=c(1,2))
> plot(hasna);plot(hasna2)
>
> # CorDistance function does not handle NAs
> CorDistance(as.vector(s[1]),as.vector(s2[1]))
> [1] 0.2192382
>
> CorDistance(as.vector(s[2]),as.vector(s2[2]))
> <simpleError in .common.ts.sanity.check(x): NA in the series>
>    [1] NA
>
> fun <- function(x,y){
>    out <- ifelse(anyNA(x) | anyNA(y),
>                  yes = NA,
>                  no = unname(CorDistance(x,y)))
>    return(out)
> }
>
> # Check that it works
> fun(as.vector(s[1]),as.vector(s2[1]))
> [1] 0.2192382
>
> # Check that it does not work
> fun(as.vector(s[2]),as.vector(s2[2]))
> [1] NA
>
> new_s1 <- fun(s,s2)
> <simpleError in if (any(is.na(x))) { stop("NA in the series")}:
>    argument is not interpretable as logical>
>
> # Check that it does not work with calc
> new_s2 <- calc(s,s2, fun = fun)
> Error in .calcTest(x[1:5], fun, na.rm, forcefun, forceapply) :
>    cannot use this function
>
> plot(s_out)
> #############
>


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