Error(s) in re-building vignettes:
  ...
--- re-building ‘landscape.Rmd’ using rmarkdown

Quitting from lines 45-56 [unnamed-chunk-3] (landscape.Rmd)
Error: processing vignette 'landscape.Rmd' failed with diagnostics:
there is no package called 'fields'
--- failed re-building ‘landscape.Rmd’

--- re-building ‘lateral-move.Rmd’ using rmarkdown

Quitting from lines 45-55 [unnamed-chunk-3] (lateral-move.Rmd)
Error: processing vignette 'lateral-move.Rmd' failed with diagnostics:
there is no package called 'fields'
--- failed re-building ‘lateral-move.Rmd’

--- re-building ‘solid-set.Rmd’ using rmarkdown

Quitting from lines 37-48 [unnamed-chunk-3] (solid-set.Rmd)
Error: processing vignette 'solid-set.Rmd' failed with diagnostics:
there is no package called 'fields'
--- failed re-building ‘solid-set.Rmd’

--- re-building ‘traveling-sys.Rmd’ using rmarkdown
** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/spreval.Rcheck/vign_test/spreval/vignettes/traveling-sys_files/figure-html/unnamed-chunk-3-1.png
384x384 pixels, 3x8 bits/pixel, RGB
Reducing image to 8 bits/pixel, grayscale
Input IDAT size = 12671 bytes
Input file size = 12758 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 4707
  zc = 9  zm = 8  zs = 1  f = 0
  zc = 1  zm = 8  zs = 2  f = 0
  zc = 9  zm = 8  zs = 3  f = 0
  zc = 9  zm = 8  zs = 0  f = 5
  zc = 9  zm = 8  zs = 1  f = 5
  zc = 1  zm = 8  zs = 2  f = 5
  zc = 9  zm = 8  zs = 3  f = 5
                               
Selecting parameters:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 4707

Output IDAT size = 4707 bytes (7964 bytes decrease)
Output file size = 4778 bytes (7980 bytes = 62.55% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/spreval.Rcheck/vign_test/spreval/vignettes/traveling-sys_files/figure-html/unnamed-chunk-4-1.png
432x432 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 16263 bytes
Input file size = 16350 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 13531
  zc = 9  zm = 8  zs = 1  f = 0
  zc = 1  zm = 8  zs = 2  f = 0
  zc = 9  zm = 8  zs = 3  f = 0
  zc = 9  zm = 8  zs = 0  f = 5
  zc = 9  zm = 8  zs = 1  f = 5
  zc = 1  zm = 8  zs = 2  f = 5
  zc = 9  zm = 8  zs = 3  f = 5
                               
Selecting parameters:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 13531

Output IDAT size = 13531 bytes (2732 bytes decrease)
Output file size = 13606 bytes (2744 bytes = 16.78% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/spreval.Rcheck/vign_test/spreval/vignettes/traveling-sys_files/figure-html/unnamed-chunk-4-2.png
432x432 pixels, 3x8 bits/pixel, RGB
Reducing image to 8 bits/pixel, grayscale
Input IDAT size = 20019 bytes
Input file size = 20118 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 7786
  zc = 9  zm = 8  zs = 1  f = 0		IDAT size = 7763
  zc = 1  zm = 8  zs = 2  f = 0
  zc = 9  zm = 8  zs = 3  f = 0
  zc = 9  zm = 8  zs = 0  f = 5
  zc = 9  zm = 8  zs = 1  f = 5
  zc = 1  zm = 8  zs = 2  f = 5
  zc = 9  zm = 8  zs = 3  f = 5
                               
Selecting parameters:
  zc = 9  zm = 8  zs = 1  f = 0		IDAT size = 7763

Output IDAT size = 7763 bytes (12256 bytes decrease)
Output file size = 7834 bytes (12284 bytes = 61.06% decrease)

--- finished re-building ‘traveling-sys.Rmd’

SUMMARY: processing the following files failed:
  ‘landscape.Rmd’ ‘lateral-move.Rmd’ ‘solid-set.Rmd’

Error: Vignette re-building failed.
Execution halted