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Visualize #R #pch (plot characters) used in #points
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# From @Greg Snow https://stackoverflow.com/a/3740473 | |
# Plots a grid with default tokens on bottom two rows, characters in others | |
png(filename="GregSnow.png", width = 600, height = 600) | |
plot( 0:15, 0:15, type='n', main = "pch values by Greg Snow" ) | |
points( (0:255)%% 16, (0:255) %/% 16, pch=0:255, font=5, cex = 2 ) | |
dev.off() | |
# From the R help for ?points | |
png(filename="PointsHelp.png", width = 600, height = 600) | |
pchShow <- | |
function(extras = c("*",".", "o","O","0","+","-","|","%","#"), | |
cex = 3, ## good for both .Device=="postscript" and "x11" | |
col = "red3", bg = "gold", coltext = "brown", cextext = 1.2, | |
main = paste("plot symbols : points (... pch = *, cex =", | |
cex,")")) | |
{ | |
nex <- length(extras) | |
np <- 26 + nex | |
ipch <- 0:(np-1) | |
k <- floor(sqrt(np)) | |
dd <- c(-1,1)/2 | |
rx <- dd + range(ix <- ipch %/% k) | |
ry <- dd + range(iy <- 3 + (k-1)- ipch %% k) | |
pch <- as.list(ipch) # list with integers & strings | |
if(nex > 0) pch[26+ 1:nex] <- as.list(extras) | |
plot(rx, ry, type = "n", axes = FALSE, xlab = "", ylab = "", main = main) | |
abline(v = ix, h = iy, col = "lightgray", lty = "dotted") | |
for(i in 1:np) { | |
pc <- pch[[i]] | |
## 'col' symbols with a 'bg'-colored interior (where available) : | |
points(ix[i], iy[i], pch = pc, col = col, bg = bg, cex = cex) | |
if(cextext > 0) | |
text(ix[i] - 0.3, iy[i], pc, col = coltext, cex = cextext) | |
} | |
} | |
pchShow() | |
dev.off() |
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Just wanted a static reference to lookup the integer codes used by pch for R point characters.
Via code from
?points
:Via StackOverflow: