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rggplot2unicodesurvminer

Displaying greater than sign in ggsurvplot (unicode errrors)

I am attempting to display a greater than sign in my strata labels for a ggsurvplot object. I generated something similar in a different plot (image below):

enter image description here

Functioning Code from Image Above

kmcurve_spd <- ggsurvplot(km_fitp1_spd, 
              palette = c("#202960", "#8CC63E", "#5B9BD5", "#8f94af"), 
              xlab = "Time (Months)", 
              legend.labs = c(paste0("<500 mm","\u00b2"), paste0("\u2265","500",
                " or <1000 mm","\u00b2"), paste0("\u2265", "1000 or <1500 mm","\u00b2"),
                paste0("\u2265","1500 mm\u00b2")))

Normally, I do not have a problem displaying > sign in a character string. However, when I try to use ">" of ">1 Prior Progressions" as a label, I keep encountering the following warning and error codes:

Warning in grid.Call(C_textBounds, as.graphicsAnnot(x$label), x$x, x$y,  :
   font family not found in Windows font database
Warning in grid.Call(C_textBounds, as.graphicsAnnot(x$label), x$x, x$y,  :
  font family not found in Windows font database
Error: gridtext has encountered a tag that isn't supported yet: <blockquote>
Only a very limited number of tags are currently supported.

Below is a truncated sample of my code that is causing the error.

Code with Error

kmcurve_pd <- ggsurvplot(km_fitp1_pd, 
              palette = c("#202960", "#8CC63E"), 
              xlab = "Time (Months)", 
              legend.labs = c(paste0("\u2265","1 Prior Progression"), ">1 Prior Progression"))

#this also generates the same error

kmcurve_pd <- ggsurvplot(km_fitp1_pd, 
              palette = c("#202960", "#8CC63E"), 
              xlab = "Time (Months)", 
              legend.labs = c(paste0("\u2265","1 Prior Progression"), 
                paste0(">","1 Prior Progression")))

However, I was able to run code when I replace the legend.labs vector with a combination of unicode and character strings, leading me to the conclusion the > is causing the error. I usually use this website to quickly search unicodes and located the unicode for the > sign: https://www.compart.com/en/unicode/U+003E

This unicode, however, seems to correspond to the wrong symbol. The code runs without any errors (only the following warning x6: Warning in grid.Call(C_textBounds, as.graphicsAnnot(x$label), x$x, x$y, : font family not found in Windows font database). Image of and code producing the incorrect symbol is below:

enter image description here

Code with Incorrect Symbol

kmcurve_pd <- ggsurvplot(km_fitp1_pd, 
              palette = c("#202960", "#8CC63E"), 
              xlab = "Time (Months)", 
              legend.labs = c(paste0("\u2264","1 Prior Progression"), paste0("\u00e3",
                "1 Prior Progression")))

Are there any workarounds so that I can get the > to display properly? I really don't want to use just words, as I have used symbols for the rest of my plots and it will look out of place. If a reprex of the KM fit object would be helpful, I can provide. Thanks!

Solution

  • Per @JosefZ's suggestion, I utilized the right arrowhead unicode to generate and it worked great. Final code with solution incorporated is below:

    kmcurve_pd <- ggsurvplot(km_fitp1_pd, 
              palette = c("#202960", "#8CC63E"), 
              xlab = "Time (Months)", 
              legend.labs = c(paste0("\u2264","1 Prior Progression"), 
                  paste0("\u02C3","1 Prior Progression"))