Default line types based on a set supplied by Richard Pearson, University of Manchester. Continuous values can not be mapped to line types.
scale_pattern_linetype(..., na.value = "blank")scale_pattern_linetype_continuous(...)
scale_pattern_linetype_discrete(..., na.value = "blank")
see ggplot2::scale_linetype
for more information
The linetype to use for NA
values.