Chcę uruchamiać skrypty R i zapisywać wątki za pomocąpng(). X11 nie jest obsługiwany na serwerach Unix i otrzymuję następujący komunikat o błędzie:

Error in X11(paste("png::", filename, sep = ""), g$width, g$height, pointsize,  : 
  unable to start device PNG
Calls: png
In addition: Warning message:
In png("test.png", width = 900, height = 400) :
  unable to open connection to X11 display ''
Execution halted

Ustawianie zmiennych środowiskowych

Sys.setenv("DISPLAY"=":0.0")

lub

Sys.setenv("DISPLAY"=":0")

skrypty R nie rozwiązały problemu.

Ten przykład kodu powoduje błąd powyżej:

library(ggplot2)
library(grid)

# Some data
df = data.frame(x = c(1.2,5,3,5.3,2,9,4,6,8,0), y = c(1.5,6,2.5,5.1,2.3,8.7,4.1,6,8,0))


# Base plot
p <- ggplot(df, aes(x,y)) + geom_point() +
   scale_x_continuous(limits = c(0, 8), expand = c(0,0)) +
   scale_y_continuous(limits = c(0, 8), expand = c(0,0)) +
   geom_smooth(method="lm", se=FALSE, formula=y~x, aes(colour="2"), show_guide=TRUE, fill=NA, size=1.2) +
   geom_vline(xintercept = 3) + geom_vline(xintercept = 7) +
   opts(plot.margin = unit(c(1,1,4,1), "lines"))

# Create the text Grobs
Text1 = textGrob("Part 1")
Text2 = textGrob("Part 2")
Text3 = textGrob("Part 3")

# Add the annotations
# Segment 1
p1 = p +
     annotation_custom(grob = linesGrob(), xmin = 0, xmax = 0, ymin = 
-1, ymax = -.75) +
     annotation_custom(grob = linesGrob(), xmin = 0, xmax = 3, ymin = 
-1, ymax = -1) +
     annotation_custom(grob = linesGrob(), xmin = 3, xmax = 3, ymin = 
-1, ymax = -.75) +
     annotation_custom(grob = Text1,  xmin = 0, xmax = 3, ymin = -1.25, 
ymax = -1.25)

# Segment 2
p1 = p1 +
     annotation_custom(grob = linesGrob(), xmin = 3, xmax = 7, ymin = 
-1, ymax = -1) +
     annotation_custom(grob = linesGrob(), xmin = 7, xmax = 7, ymin = 
-1, ymax = -.75) +
     annotation_custom(grob = Text2,   xmin = 3, xmax = 7, ymin = -1.25, 
ymax = -1.25)

# Segment 3
p1 = p1 +
     annotation_custom(grob = linesGrob(), xmin = 7, xmax = 8, ymin = 
-1, ymax = -1) +
     annotation_custom(grob = linesGrob(), xmin = 8, xmax = 8, ymin = 
-1, ymax = -.75) +
     annotation_custom(grob = Text3,  xmin = 7, xmax = 8, ymin = -1.25, 
ymax = -1.25)

png("test.png", width=900, height=400)

# Code to override clipping
gt <- ggplot_gtable(ggplot_build(p1))
gt$layout$clip[gt$layout$name=="panel"] <- "off"
grid.draw(gt)

dev.off()

Wynikcapabilities() jest:

   jpeg      png     tiff    tcltk      X11     aqua http/ftp  sockets 
   FALSE    FALSE    FALSE     TRUE    FALSE    FALSE     TRUE     TRUE 

  libxml     fifo   cledit    iconv      NLS  profmem    cairo 
    TRUE     TRUE    FALSE     TRUE     TRUE    FALSE    FALSE

Korzystam ze skryptów za pomocą silnika Sun grid.