Apparently, my brain cannot retain the R *pch* code index on its own. And I got tired of Google-Imaging (is that a legit verb?) “R *pch*” every time I needed to sort out a symbol. So I made a quick plot (mostly for my own use) of all the *pch* symbols (to add to the hundreds of others on the internet). So here it is.

The *pch* code is (somewhat obviously) the sum of the Y and X coordinates on the plot.

e.g. the *@* symbol is *pch=60+4* or *64*.

Incidentally, I also came across this post on how to use unicode (hexidecimal) symbols on your R plots. Maybe there’s a Death Star symbol in there that I can sneak into a publication some time.

For the three of you who just must know how this is coded:

# Make the data pch.dat <- data.frame(expand.grid(X=1:10, Y=seq(0,250,10)), PCH=1:260) # Set up the plot window graphics.off() x11(w=7, h=11) par(mar=c(5,5,3,5)) # Make the plot plot(Y~X, data=pch.dat, type="n", axes=F)#, main="R pch = X + Y") abline(h=seq(0,250,10), col="gray90", lwd=20) abline(v=1:10, col="gray90", lwd=20) points(Y~X, data=pch.dat, pch=pch.dat$PCH, cex=1.2, col="black", bg="red") axis(1, at=1:10, las=1) axis(2, at=seq(0,250,10), las=1) axis(3, at=1:10, las=1) axis(4, at=seq(0,250,10), las=1) box() savePlot("R_pch_plot.png", type="png")

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