Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Error(s) in re-building vignettes:
  ...
--- re-building ‘Using_fontMPlus.Rmd’ using rmarkdown
Quitting from lines 56-67 (Using_fontMPlus.Rmd) 
Error: processing vignette 'Using_fontMPlus.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘Using_fontMPlus.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Error(s) in re-building vignettes:
  ...
--- re-building ‘Using_fontMPlus.Rmd’ using rmarkdown
Quitting from lines 56-67 (Using_fontMPlus.Rmd) 
Error: processing vignette 'Using_fontMPlus.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘Using_fontMPlus.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Error(s) in re-building vignettes:
  ...
--- re-building ‘Using_fontMPlus.Rmd’ using rmarkdown
Quitting from lines 56-67 (Using_fontMPlus.Rmd) 
Error: processing vignette 'Using_fontMPlus.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘Using_fontMPlus.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Namespace in Imports field not imported from: ‘ggplot2’
  All declared Imports should be used.
Error(s) in re-building vignettes:
  ...
--- re-building ‘Using_fontMPlus.Rmd’ using rmarkdown
Quitting from lines 56-67 (Using_fontMPlus.Rmd) 
Error: processing vignette 'Using_fontMPlus.Rmd' failed with diagnostics:
polygon edge not found
--- failed re-building ‘Using_fontMPlus.Rmd’

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

Error: Vignette re-building failed.
Execution halted