Rspatial terra::flip error when flipping a multi-layer spatRast object

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I opened a .nc raster file with terra::rast. It has 42 bands. The raster reads in upside down & needs to be flipped vertically. When I flip one band from the spatRast object, it flips properly. code below

library(terra)

s2file <- "S2A_MSI_2018_07_24_18_49_21_T10SFH_L2W.nc"
S2Rrs <- rast(s2file)

S2Rrs
#class       : SpatRaster 
#dimensions  : 5490, 5490, 41  (nrow, ncol, nlyr)
#resolution  : 1, 1  (x, y)
#extent      : 0.5, 5490.5, 0.5, 5490.5  (xmin, xmax, ymin, ymax)
#coord. ref. :  
#sources     : S2A_MSI_2018_07_24_18_49_21_T10SFH_L2W.nc:spm_nechad  
#              S2A_MSI_2018_07_24_18_49_21_T10SFH_L2W.nc:spm_nechad2016  
#              S2A_MSI_2018_07_24_18_49_21_T10SFH_L2W.nc:t_nechad  
#              ... and 38 more source(s)
#varnames    : spm_nechad (Suspended Particulate Matter) 
#              spm_nechad2016 (Suspended Particulate Matter) 
#              t_nechad (Water turbidity) 
#              ...
#names       : spm_nechad, spm_n~d2016, t_nechad, t_nechad2016, t_dogliotti, chl_re_gons, ... 
#unit        :     g m^-3,      g m^-3,      FNU,          FNU,         FNU,     mg m^-3, ... 

names(S2Rrs)
# [1] "spm_nechad"        "spm_nechad2016"    "t_nechad"         
# [4] "t_nechad2016"      "t_dogliotti"       "chl_re_gons"      
# [7] "chl_re_moses3b"    "chl_re_moses3b740" "chl_re_gons740"   
#[10] "chl_re_mishra"     "slh"               "a443_qaasw"       
#[13] "a490_qaasw"        "a560_qaasw"        "a665_qaasw"       
#[16] "bbp443_qaasw"      "bbp490_qaasw"      "bbp560_qaasw"     
#[19] "bbp665_qaasw"      "rhos_443"          "rhos_492"         
#[22] "rhos_560"          "rhos_665"          "rhos_704"         
#[25] "rhos_740"          "rhos_783"          "rhos_833"         
#[28] "rhos_865"          "rhos_1614"         "rhos_2202"        
#[31] "Rrs_443"           "Rrs_492"           "Rrs_560"          
#[34] "Rrs_665"           "Rrs_704"           "Rrs_740"          
#[37] "Rrs_783"           "Rrs_833"           "Rrs_865"          
#[40] "Rrs_1614"          "Rrs_2202"     

I then assign the CRS & extent

rastcrs <- "+proj=utm +zone=10 +datum=WGS84 +units=m +no_defs"
rextent <- c(600000, 709800, 4190220, 4300020)

When I try to flip the whole object, I get this error:

x <- flip(S2Rrs)
#Error: [flip] too few values for writing: 32863140 < 150360120
#In addition: There were 41 warnings (use warnings() to see them)

One layer plots like this:

Single band plot

The input file is 5G.

I haven't found any guidance for this online. I tried flipping one layer from the spatRast object. A single layer flips properly, and plots rightside up.

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Robert Hijmans On

I can reproduce this with the current CRAN version of terra

library(terra)
#terra 1.7.55
s <- rast(system.file("ex/logo.tif", package="terra"))   
terraOptions(todisk=TRUE)
y <- flip(s*1, steps=2)
#Error: [flip] too many values for writing: 11817 > 11514

This is a bug that affects some large raster datasets that have to be processed in chunks. It has now been fixed in "terra" version 1.7.57 (currently the development version). You should be able to install this version of terra from the R-Universe with

install.packages('terra', repos='https://rspatial.r-universe.dev')