Differences

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--- software:gnuplot [2012/02/08 16:40]
cyril [set]
+++ software:gnuplot [2024/04/19 09:54] (current)
cyril autotitle
@@ Line 59: / Line 59: @@
 set x2label ""
 set y2label ""
+</code>
+  * Log scale.<code gnuplot>
+set logscale x 2
+set logscale y 10
 </code>
@@ Line 69: / Line 74: @@
 set key left bottom
 set key 100,100
+</code>
+  * Automatic legend.<code gnuplot>
+set key autotitle columnheader
 </code>
@@ Line 137: / Line 146: @@
   * **every** Specifying lines to use (every 2 lines from line 50 to line 1050).<code gnuplot>
 plot "data.dat" using 4:5 every 2::50::1050
+</code>
+  * **separator** Set the field separator:<code gnuplot>
+set datafile separator ","
 </code>
@@ Line 159: / Line 172: @@
 plot "data1.dat" using 4:5 lt rgb "red"
 plot "data1.dat" using 4:5 lt rgb "#FF0000"
+</code>
+  * **palette** Colors as value.<code gnuplot>
+set palette defined (0 "black", 1 "red")
+plot "data1.dat" using 1:2:0 w p palette
 </code>
@@ Line 190: / Line 208: @@
 </code>
-  * **($1)** Arithmetics on columns.<code gnuplot>
+  * **($1)** Arithmetics on columns data.<code gnuplot>
 plot "data1.dat" using 4:($5/2+14)
 # where $n means column n
+</code>
+  * **(column())** Arithmetics on columns indices.<code gnuplot>
+plot i=1, "data1.dat" using 1:(column(i+1))
 </code>
@@ Line 203: / Line 225: @@
 plot "gps.dat" using (rotation_x($3,$4)):(rotation_y($3,$4))
+</code>
+  * **word()** Define array variables.<code gnuplot>
+colors="red blue green"
+print word(colors,3)
 </code>
@@ Line 214: / Line 241: @@
 plot for [file in "run1.dat run2.dat run3.dat"] file using 1:2
 </code><code gnuplot>
-plot for [i=1:3] run.dat using i
+plot for [i=1:3] run.dat using i t sprintf("curve %s", columnheader(i))
 </code><code gnuplot>
 file(n) = sprintf("run_%d.dat",n)
@@ Line 250: / Line 277: @@
 plot "< awk 'NR==1 { prev=$2 } NR>1 { dt=$2-prev; prev=$2; print $1,dt; }' idSlamDala.dat" using 1:2
 </code>
-    * Sliding mean.<code gnuplot>
+    * Bins mean + eval.<code gnuplot>
+myplot(x,t) = sprintf("plot \"< awk '\
+    NR==1 { i=0; s=0; for(j=0;j<$ARGV_NMEAN;j++) tab[j]=0; } \
+    NR>=1 { s=s-tab[i]; tab[i]=\$%d; s=s+tab[i]; i=(i>=($ARGV_NMEAN-1)?0:i+1); } \
+    NR>$ARGV_NMEAN { if (i==0) print s/$ARGV_NMEAN; }' $ARGV_FILE\"\
+    using 1 t \"%s\"", x, t)
+eval myplot(2, "ax")
+</code>
+    * Sliding mean + continous angle + gunzip.<code gnuplot>
 plot "< gunzip -c $ARGV_FILE | awk '\
     NR==1 { k=0; prev_a=0; i=0; pi=3.14159265358979 } \
@@ Line 265: / Line 300: @@
 plot "< gunzip -c file.dat" using 1:($4-$2)
 plot "< zcat file.dat" using 1:($4-$2)
+plot "< tar -Oxjf file.dat.tar.bz2" using 1:($4-$2)
 </code>
   * or anything else with shell commands...
+  * **fit** a function to data:<code gnuplot>
+f(x) = a*x**2 + b*x + c
+fit f(x) "file.dat" u 1:2 via a,b,c
+plot "file.dat" u 1:2, f(x)
+</code>
   * **sh** Passing arguments to a gnuplot script.
-    * Putting the gnuplot commands in a shell script (be careful, if you forget a backslash in front of a gnuplot dollar the error message can seem mysterious):<code gnuplot|plot.gp>
+    * (preferred method) Putting the gnuplot commands in a shell script (be careful, if you forget a backslash in front of a gnuplot dollar the error message can seem mysterious):<code gnuplot|plot.gp>
 #!/bin/sh
 ARGV1=$1
@@ Line 278: / Line 320: @@
 </code><code sh>
 ./plot.gp run.dat
+</code>You can also build a more complicated plot file with multiple steps (for multiplot or multiple curves):<code gnuplot>
+#!/bin/sh
+######
+script_header=`cat<<EOF
+set term wxt size 1024,768
+set grid
+plot \
+EOF
+`
+script=$script_header
+######
+for host in $*; do
+script_loop=`cat<<EOF
+    "file_$host.log" u 4:5 w l lt rgb "blue" t "Position $host", \
+EOF
+`
+script="$script$script_loop"
+done
+######
+script_footer=`cat<<EOF
+pause -1
+EOF
+`
+script="$script$script_footer"
+gnuplot<<EOF
+$(echo "$script")
+EOF
 </code>
     * Writing a generic launcher script with environment variables (but difficulty to deal with relative paths):<code sh|gplaunch>
@@ Line 316: / Line 387: @@
 !epstopdf --outfile=plot.pdf plot.eps
 quit
-</code>By default, when exporting to ps or pdf, gnuplot changes the lines style with dashes so that they can be recognized when printed in black and white. If you want to keep your lines plain, you can add the "linestyle 1" command:<code gnuplot>
+</code>By default, when exporting to ps or pdf, gnuplot changes the lines style with dashes so that they can be recognized when printed in black and white. If you want to keep your lines plain, you can either add the "solid" option to the terminal command, or add the "ls 1" command:<code gnuplot>
-plot [...] with lines linestyle 1 lt rgb "red"
+plot [...] with lines ls 1 lw 2 lt rgb "red"
+</code>Also the grid is black by default, if you want to set it to grey:<code gnuplot>
+set grid lc rgb "grey"
 </code>
@@ Line 345: / Line 418: @@
 !gzip -S z plot.svg
 quit
+</code>
+  * Conditional output:<code gnuplot>
+#!/bin/sh
+TITLE=plot
+if [[ $1 == "pdf" ]]; then
+    GTERM='set terminal postscript eps color "Times-Roman" 16 solid size 5,2.9 ; set output "$TITLE.eps"'
+    OUTPUT='!epstopdf --outfile=$TITLE.pdf $TITLE.eps'
+    GRIDCOLOR='lc rgb "grey"'
+    shift
+elif [[ $1 == "png" ]]; then
+    GTERM='set terminal pngcairo font "Times,32" size 1830,1780 ; set output "$TITLE.png"'
+    OUTPUT=''
+    GRIDCOLOR=''
+    shift
+else
+    GTERM='set term wxt size 1024,768'
+    OUTPUT=''
+    GRIDCOLOR=''
+fi
+gnuplot -persist << EOF
+$GTERM
+set grid $GRIDCOLOR
+# your plotting code (can be included using the load command)
+set output
+    $OUTPUT
+EOF
+</code>
+===== Interactivity =====
+  * Keyboard bindings<code gnuplot>
+bind "a" "plot x*x"
+</code>
+  * Progressive display (but the plot is not interactive anymore)<code gnuplot>
+plot "file.dat" u 1
+while(1) { replot ; pause 0.2 }
+</code>
+  * Pausing and resuming the progressive display for interactivity (only works with x11 terminal if started in interactive gnuplot shell... for wxt terminal the event processing loop -- wxt_gui.cpp:wxt_waitforinput function -- is not called during the update loop, but ctrl-c in the shell stops the update loop and allows plot interactivity afterwards, contrary to x11 term...).<code gnuplot>
+set terminal x11
+bind "c" "update=1-update ; while(update) { replot ; pause 0.1 }"
+plot "file.dat" u 1
+update=1
+while(update) { replot ; pause 0.2 }
 </code>