gnuplot epslatex terminal problematic dvi or ps output - gnuplot

Question

I am using the epslatex terminal to generate eps figures with gnuplot 4.6.4.
However, I am having problem with this script
# reset
reset
#
sz = 1.4
rx = 10.0/7.0
#
set style line 1 lt 1 pointsize 1
# blue line
set style line 2 lt 12 pointsize 1
#
set terminal epslatex size rx*sz,2*sz color standalone
set output 'output.tex'
set multiplot layout 2,2
# Figure 1,1
set tmargin 0
set bmargin 0
set lmargin at screen 0.05
set rmargin at screen 0.475
set format x ""
set xrange [30:130]
set ylabel offset 2,0 "Y label [sec]"
unset xlabel
set grid
set yrange [0:9]
set ytics ("" 0, "1" 1, "2" 2, "3" 3, "4" 4, \
"5" 5, "6" 6, "7" 7, "8" 8, "" 9)
unset key
plot "./inp" u 1:2 t "tsL" w lp ls 1, \
"" u 1:3 t "vL" w lp ls 2
#
# Figure 1,2
set bmargin 0
set tmargin 0
set lmargin at screen 0.525
set rmargin at screen 0.95
set format x ""
set format y ""
set xrange [30:130]
set yrange [0:9]
#set mytics 2
unset ylabel
unset xlabel
set grid
plot "./inp" u 1:2 t "tsL" w lp ls 1, \
"" u 1:3 t "vL" w lp ls 2
# Figure 2,1
set tmargin 0
set bmargin 0
set lmargin at screen 0.05
set rmargin at screen 0.475
set format x "%g"
set format y "%g"
set xrange [30:130]
set ylabel offset 2,0 "Ylabel"
set xlabel offset 0,0.6 "neig"
set grid
set yrange [0:9]
set ytics ("" 0, "1" 1, "2" 2, "3" 3, "4" 4, \
"5" 5, "6" 6, "7" 7, "8" 8, "" 9)
unset key
set xtics ("40" 40, "" 60 , "80" 80,\
"" 100, "120" 120)
set mxtics 2
plot "./inp" u 1:2 t "tsL" w lp ls 1, \
"" u 1:3 t "vL" w lp ls 2
#
# Figure 2,2
set bmargin 0
set tmargin 0
set lmargin at screen 0.525
set rmargin at screen 0.95
set format y ""
set format x "%g"
set xrange [30:130]
set yrange [0:9]
#set ylabel "Ylabel"
unset ylabel
set xlabel offset 0,0.6 "neig"
set grid
set xtics ("40" 40, "" 60 , "80" 80,\
"" 100, "120" 120)
set mxtics 2
plot "./inp" u 1:2 t "tsL" w lp ls 1, \
"" u 1:3 t "vL" w lp ls 2
#
unset multiplot
#
set output
with the input file inp which includes
40 1 3
60 2 4
80 3 5
100 4 6
120 5 7
If I compile the document, everything goes fine. However, there is a line missing in dvi file and the labels seem to be at wrong location. After that, if I execute "dvips output.dvi", I get a completely wrong ps output without any labels and ytics at the wrong location. What is my mistake with this implementation?

Answer 1

The dvi output is usually wrong, especially the labels, because these are typeset with Postscript operations, which aren't interpreted correctly by many dvi viewers.
Concerning the labels, your left margins are too small, so that the labels are outside of the image. For you example I had to use
set lmargin at screen 0.2
set ylabel offset 0.5,0 "Y label [sec]"
for Figure 1,1 in order to have reasonable margins and see all labels (ytic labels and ylabel). The ytics are ok.
In the same manner you have to fix the other settings of lmargin and rmargin of the other subfigures, and also the bmargin of the bottom row in order to see the xlabel and the xtic labels.
And you don't need to set the ytics manually. Use
set ytics 1,1,8 # tics from 1 to 8 in steps of 1
set xtics 40 # distance of 40 between tics.
Margins and plot area
Some remarks about the margins, plot area and canvas size.
The image size (i.e. the canvas size) is given by the size terminal option (e.g. set terminal pngcairo size 800,400).
Usually, the size and position of the plotting area inside the canvas is determined automatically based on several points:
Font size
Presence and position of xlabel, ylabel etc, title, key being outside, colorbox, length of tic labels and so on.
The plotting area can be changed relative to the automatically determined one by set size and set origin (and for splot it can be scaled with set view).
The plotting area can also be set fixed by specifying explicit margins. In this case the user has to care about providing large enough margins to fit in all the elements. The margins can be specified independently with set lmargin, set rmargin, set bmargin and set tmargin. Their values can be specified in two ways:
set tmargin 1 leaves a top margin equivalent to one character height.
set tmargin at screen 0.95 leaves a top margin of 5% of the total canvas size.