Error(s) in re-building vignettes:
--- re-building ‘freq-uncertainty-vis.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


Attaching package: 'modelr'

The following object is masked from 'package:broom':

    bootstrap

Quitting from lines 91-95 (freq-uncertainty-vis.Rmd) 
Error: processing vignette 'freq-uncertainty-vis.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘freq-uncertainty-vis.Rmd’

--- re-building ‘lineribbon.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 112-116 (lineribbon.Rmd) 
Error: processing vignette 'lineribbon.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘lineribbon.Rmd’

--- re-building ‘slabinterval.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 71-152 (slabinterval.Rmd) 
Error: processing vignette 'slabinterval.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘slabinterval.Rmd’

SUMMARY: processing the following files failed:
  ‘freq-uncertainty-vis.Rmd’ ‘lineribbon.Rmd’ ‘slabinterval.Rmd’

Error: Vignette re-building failed.
Execution halted