- > 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()
