Error(s) in re-building vignettes:
  ...
--- re-building 'GEVACO_Intro.Rmd' using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building 'GEVACO_Intro.Rmd'

SUMMARY: processing the following file failed:
  'GEVACO_Intro.Rmd'

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
  ...
--- re-building ‘GEVACO_Intro.Rmd’ using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette ‘GEVACO_Intro.Rmd’ failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building ‘GEVACO_Intro.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building ‘GEVACO_Intro.Rmd’ using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building ‘GEVACO_Intro.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building ‘GEVACO_Intro.Rmd’ using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building ‘GEVACO_Intro.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'GEVACO_Intro.Rmd' using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building 'GEVACO_Intro.Rmd'

SUMMARY: processing the following file failed:
  'GEVACO_Intro.Rmd'

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'GEVACO_Intro.Rmd' using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building 'GEVACO_Intro.Rmd'

SUMMARY: processing the following file failed:
  'GEVACO_Intro.Rmd'

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
  ...
--- re-building ‘GEVACO_Intro.Rmd’ using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building ‘GEVACO_Intro.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
  ...
--- re-building ‘GEVACO_Intro.Rmd’ using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building ‘GEVACO_Intro.Rmd’

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

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'GEVACO_Intro.Rmd' using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building 'GEVACO_Intro.Rmd'

SUMMARY: processing the following file failed:
  'GEVACO_Intro.Rmd'

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'GEVACO_Intro.Rmd' using rmarkdown
Quitting from lines 24-38 (GEVACO_Intro.Rmd) 
Error: processing vignette 'GEVACO_Intro.Rmd' failed with diagnostics:
attempt to use zero-length variable name
--- failed re-building 'GEVACO_Intro.Rmd'

SUMMARY: processing the following file failed:
  'GEVACO_Intro.Rmd'

Error: Vignette re-building failed.
Execution halted