Error(s) in re-building vignettes:
--- re-building ‘distances.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Quitting from lines 114-116 (distances.Rmd) 
Error: processing vignette 'distances.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘distances.Rmd’

--- re-building ‘nullabor-examples.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Warning: Removed 20 rows containing missing values (geom_rect).
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_stringMetric, as.graphicsAnnot(x$label)) :
  no font could be found for family "Arial"
Warning in grid.Call(C_textBounds, as.graphicsAnnot(x$label), x$x, x$y,  :
  no font could be found for family "Arial"
Quitting from lines 78-95 (nullabor-examples.Rmd) 
Error: processing vignette 'nullabor-examples.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘nullabor-examples.Rmd’

--- re-building ‘nullabor.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Quitting from lines 48-49 (nullabor.Rmd) 
Error: processing vignette 'nullabor.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘nullabor.Rmd’

SUMMARY: processing the following files failed:
  ‘distances.Rmd’ ‘nullabor-examples.Rmd’ ‘nullabor.Rmd’

Error: Vignette re-building failed.
Execution halted