What are the units of width in tm_scalebar() #1168
Description
I got the following error message when I supplied 0.5 for the width in tm_scalebar. Eventually I figured out that it needed fairly large numbers but I still don't know what the units of width are. It is not described in the documentation. It would be great to have a more clear error message and details on the units in the docs.
Thanks!!
library(tmap)
tm_shape(World, bbox = World) +
tm_text("name", size="pop_est", col="continent",
col.scale = tm_scale_categorical(values = "seaborn.dark"),
col.legend = tm_legend_hide(),
size.scale = tm_scale_continuous(values.scale = 4),
size.legend = tm_legend_hide())+
tm_scalebar(width = 0.5)
#> [tip] Consider a suitable map projection, e.g. by adding `+ tm_crs("auto")`.
#> Scale bar set for latitude km and will be different at the top and bottom of the map.
#>
#> This message is displayed once per session.
#> Error in tmapGridCompPlot.tm_scalebar(X[[i]], ...): object 'sbW' not found
tm_shape(World, bbox = World) +
tm_text("name", size="pop_est", col="continent",
col.scale = tm_scale_categorical(values = "seaborn.dark"),
col.legend = tm_legend_hide(),
size.scale = tm_scale_continuous(values.scale = 4),
size.legend = tm_legend_hide())+
tm_scalebar(width = 10)
#> Scale bar set for latitude km and will be different at the top and bottom of the map.tm_shape(World, bbox = World) +
tm_text("name", size="pop_est", col="continent",
col.scale = tm_scale_categorical(values = "seaborn.dark"),
col.legend = tm_legend_hide(),
size.scale = tm_scale_continuous(values.scale = 4),
size.legend = tm_legend_hide())+
tm_scalebar(width = 100)
#> Scale bar set for latitude km and will be different at the top and bottom of the map.Created on 2025-07-16 with reprex v2.1.1