Re: [Gretl-users] Problems with R function in foreign block

On Fri, 9 Mar 2018, Artur Tarassow wrote: This is maybe off-topic, but I took a further look. I know that R is capable of producing very nice data graphics, but the language to control graphics seems to me a rabbit-hole of doom. Comments beow relate to R-3.4.3 on Fedora 26. The two packages you loaded in your script at http://lists.wfu.edu/pipermail/gretl-users/2018-March/013035.html , namely Cairo and cairoDevice, are not complementary, they're competitors (not unusual for R packages). So I've tried each of them individually (script below). Both of them work when the script is run in gretlcli -- and in that context cairoDevice is better in one way: it respects your request to use the Times font, which is ignored by the Cairo package. However, when run via the gretl GUI the cairoDevice variant fails. Neither of the packages respects your par() setting of "las=1" (axis labels always horizontal). The graphics system seems to depend on a bunch of inscrutable global variables over which the packages have an insecure degree of control. Maybe it's unfair, but I have a sense of package writers not quite knowing what they're doing in this area. Or maybe the API has been changed since the packages were written. As for the flashing (or persistent) X11 window showing a simplified version of the plot we're trying to write to PNG, it seems to be a feature of R that you can't turn that off. However, by sticking "dev.off()" before the call to Cairo() I was able (on my system at any rate) to get the X11 window just to flash, and not persist, when using gretl_x11. (Using gretlcli it always just flashed.) <hansl> set verbose off set R_functions on foreign language=R HIST_R1 <- function(X, fname) { # package Cairo 1.5-9 (2015-09-26) library(Cairo) H1 <- hist(X[,1]) H2 <- hist(X[,2]) H3 <- hist(X[,3]) dev.off() # dimensions in pixels CairoPNG(filename=fname, width=600, height=600, pointsize=14) par(family="Times", las=1) plot(H1, col=rgb(0,0,0,1/2), xlab="", main="") plot(H2, add=T, col=rgb(0.5,0.5,0.5,1/2)) plot(H3, add=T, col=rgb(1,1,1,1/2)) dev.off() 0 } HIST_R2 <- function(X, fname) { # package cairoDevice 2.24 (2017-01-06) library(cairoDevice) H1 <- hist(X[,1]) H2 <- hist(X[,2]) H3 <- hist(X[,3]) dev.off() # dimensions nominally in inches Cairo_png(filename=fname, width=7, height=7, pointsize=14) par(family="Times", las=1) plot(H1, col=rgb(0,0,0,1/2), xlab="", main="") plot(H2, add=T, col=rgb(0.5,0.5,0.5,1/2)) plot(H3, add=T, col=rgb(1,1,1,1/2)) dev.off() 0 } end foreign # example calls matrix M = mnormal(200, 3) # does not respect choice of font family via par() printf "Calling R.HIST_R1\n" fname = sprintf("%s/Rhist1.png", $workdir) scalar rret = R.HIST_R1(M, fname) print rret # fails when called via gretl GUI, but OK in gretlcli printf "Calling R.HIST_R2\n" fname = sprintf("%s/Rhist2.png", $workdir) scalar rret = R.HIST_R2(M, fname) print rret </hansl> Allin