Differences

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--- software:gnuplot [2013/05/28 15:52]
cyril [File outputs]
+++ 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 277: / Line 304: @@
   * 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=$1
@@ Line 287: / Line 320: @@
 </code><code sh>
 ./plot.gp run.dat
+</code>You can also build a more complicated plot file with multiple steps (for multiplot or multiple curves):<code gnuplot>
+#!/bin/sh
+######
+script_header=`cat<<EOF
+set term wxt size 1024,768
+set grid
+plot \
+EOF
+`
+script=$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 356: / 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>