[R-sig-Geo] terra::app

[Bede-Fazekas Ákos]

Dear Jonathan,

Function get.snow() is not vectorized, i.e. it does not return a vector 
of the same length as its input. According to the help of app(), "The 
function should return a vector or matrix that is divisible by ncell(x).".

HTH,
Ákos Bede-Fazekas
Centre for Ecological Research
Hungary

2022.09.29. 5:27 keltezéssel, Thayn, Jonathan írta:
> I keep getting the following message when using terra:app –– Error: [app] the number of values returned by 'fun' is not appropriate. I can’t figure out what I’m doing wrong. A sample code is below:
>
>
>
>
> library(terra)
> the.raster <- rast(ncol=4,nrow=4)
> the.raster[] <- sample(0:65535,16)
>
> get.snow <- function(j){
> k <- as.numeric(intToBits(j)[10:11])
> m <- k%*%1:2
> return(m)
> }
>
> new.raster <- app(the.raster,get.snow)
>
>
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>
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