Error(s) in re-building vignettes:
  ...
--- re-building ‘overview.Rmd’ using rmarkdown_notangle
** Processing: /home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/solartime.Rcheck/vign_test/solartime/vignettes/overview_files/figure-html/eccentricityPlot-1.png
412x307 pixels, 8 bits/pixel, 256 colors in palette
Reducing image to 8 bits/pixel, grayscale
Input IDAT size = 8653 bytes
Input file size = 9523 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 7945
  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 = 7945

Output IDAT size = 7945 bytes (708 bytes decrease)
Output file size = 8023 bytes (1500 bytes = 15.75% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/solartime.Rcheck/vign_test/solartime/vignettes/overview_files/figure-html/polarSunrise-1.png
412x307 pixels, 8 bits/pixel, 256 colors in palette
Reducing image to 8 bits/pixel, grayscale
Input IDAT size = 8441 bytes
Input file size = 9311 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 7581
  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 = 7581

Output IDAT size = 7581 bytes (860 bytes decrease)
Output file size = 7659 bytes (1652 bytes = 17.74% decrease)

** Processing: /home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/solartime.Rcheck/vign_test/solartime/vignettes/overview_files/figure-html/isDayPlot-1.png
412x307 pixels, 8 bits/pixel, 256 colors in palette
Reducing image to 8 bits/pixel, grayscale
Input IDAT size = 6125 bytes
Input file size = 6983 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 5536
  zc = 9  zm = 8  zs = 1  f = 0		IDAT size = 5509
  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 = 5509

Output IDAT size = 5509 bytes (616 bytes decrease)
Output file size = 5587 bytes (1396 bytes = 19.99% decrease)


Quitting from lines 167-174 [unnamed-chunk-7] (overview.Rmd)
Error: processing vignette 'overview.Rmd' failed with diagnostics:
CCTZ: Unrecognized timezone of the input vector: ""
--- failed re-building ‘overview.Rmd’

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

Error: Vignette re-building failed.
Execution halted