gnuplot bug (?) plotting datafile

2
votes

I wrote the following "tmp.dat" datafile

\# 0;1;2;3;4;5;6;7;8;9;10;11;12;13;14;15;16;17;18;19;20
\#inFile;cn;mv;nr;nd;nn;fil;sep;m#enn=;m#enn=;n=;i=;aLea1=;rLea1=;amea1=;rmea1=;NbaLea1=;NbrLea1=;Nbamea1=;Nbrmea1=;rrmen3a1=
ex32new_DMLPG_beta3_der1emeno5/fort.501;0;?;?;?;?;0.0110485435;0.0078125;14;11.1540828402;4225;0;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00172
ex32new_DMLPG_beta3_der1emeno5/fort.501;1;0.0165088727;1745;64;0;0.0441941738;0.0078125;42;11.2126074499;1745;1;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00172
ex32new_DMLPG_beta3_der1emeno5/fort.501;2;0.0165088858;1726;64;0;0.0441941738;0.0078125;35;11.2027809965;1726;2;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00272
ex32new_DMLPG_beta3_der1emeno5/fort.501;3;0.0165088801;1724;64;0;0.0441941738;0.0078125;39;11.214037123;1724;3;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00372
ex32new_DMLPG_beta3_der1emeno5/fort.501;4;0.0165088766;1720;64;0;0.0441941738;0.0078125;34;11.1831395349;1720;4;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00472
ex32new_DMLPG_beta3_der1emeno5/fort.501;5;0.0165088776;1718;64;0;0.0441941738;0.0078125;32;11.1850989523;1718;5;0.00898;0.00158;0.00205;0.00204;0.00898;0.00158;0.00205;0.00204;0.00572
ex32new_DMLPG_beta3_der1emeno5/fort.501;6;0.0165088822;1710;64;0;0.0441941738;0.0078125;34;11.216374269;1710;6;0.00898;0.00158;0.00205;0.00205;0.00898;0.00158;0.00205;0.00205;0.00672

My gnuplot script

set datafile separator ";"
set datafile missing "?"

set grid

set xlabel "coarsening level"

set ylabel "rrmen3a1"

set xrange [-1:7]
set yrange [*:*]

set terminal pdf color
set output "tmp.pdf"

plot \
"tmp.dat" using 2:21 index 0 with lp title columnheader(1), \

#    EOF

does NOT plot the "first" point (0, 0.00172), only points x=1,...,6 Any hint?

1
gnuplot
The first line is consumed by title columnheader - Christoph
stackoverflow.com/q/28346228/2604213 - Christoph

1 Answers

1
votes

The issue is with your plot line

plot "tmp.dat" using 2:21 index 0 with lp title columnheader(1)

This instructs gnuplot to use your first record (which does not include commented lines) to use as column labels. So your first data line is being interpreted as a header. If you do not want to reformat your datafiles, you can plot a dummy curve with the same header file which will act as your data series label. Something like

plot "tmp.dat" using 2:21       index 0 with lp lt 1 lc rgb 'black' notitle, \
     "tmp.dat" using ($0):(1/0) index 0 with lp lt 1 lc rgb 'black' columnhead(1)

Note that we have to manually specify the line styles to ensure the keys have the same linestyle as the curves.