Error(s) in re-building vignettes:
  ...
--- re-building ‘exampleBackShift.Rmd’ using rmarkdown
** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/backShift.Rcheck/vign_test/backShift/vignettes/exampleBackShift_files/figure-html/unnamed-chunk-8-1.png
576x576 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 39812 bytes
Input file size = 39938 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 32281
  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 = 32281

Output IDAT size = 32281 bytes (7531 bytes decrease)
Output file size = 32359 bytes (7579 bytes = 18.98% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/backShift.Rcheck/vign_test/backShift/vignettes/exampleBackShift_files/figure-html/unnamed-chunk-9-1.png
576x576 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 41820 bytes
Input file size = 41958 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 33837
  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 = 33837

Output IDAT size = 33837 bytes (7983 bytes decrease)
Output file size = 33915 bytes (8043 bytes = 19.17% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/backShift.Rcheck/vign_test/backShift/vignettes/exampleBackShift_files/figure-html/unnamed-chunk-10-1.png
576x576 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 39573 bytes
Input file size = 39699 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 32281
  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 = 32281

Output IDAT size = 32281 bytes (7292 bytes decrease)
Output file size = 32359 bytes (7340 bytes = 18.49% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/backShift.Rcheck/vign_test/backShift/vignettes/exampleBackShift_files/figure-html/unnamed-chunk-13-1.png
960x720 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 92267 bytes
Input file size = 92477 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 87103
  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 = 87103

Output IDAT size = 87103 bytes (5164 bytes decrease)
Output file size = 87181 bytes (5296 bytes = 5.73% decrease)


Quitting from lines 269-272 [unnamed-chunk-14] (exampleBackShift.Rmd)
Error: processing vignette 'exampleBackShift.Rmd' failed with diagnostics:
there is no package called 'fields'
--- failed re-building ‘exampleBackShift.Rmd’

SUMMARY: processing the following file failed:
  ‘exampleBackShift.Rmd’

Error: Vignette re-building failed.
Execution halted