I want to plot the following function
sum a*exp(-0.001*(x-b)**2)
where a and b values are listed in the 1st and 2nd columns of an input file respectively, like this
a1 b1
a2 b2
a3 b3
.....
an bn
now I am plotting it using the following command
plot a1*exp(-0.001*(x-b1)**2) + a2*exp(-0.001*(x-b2)**2) + a1*exp(-0.001*(x-b3)**2) ...etc
what I need is a short command to plot all data without writing all the data one by one.
the expected output should be one continuous line like this
The simplest is probably to use awk to generate the wanted plot command. For example,
f(a,b,x)=a*exp(-0.001*(x-b)**2)
sum(x) = `awk <data '{v = v sprintf("f(%s,%s,x)+",$1,$2)} END{print v "0"}'`
set xrange [250:650]
plot sum(x)
This uses backticks inside the gnuplot command file to run awk which reads from the data file and generates a string like:
f(1,2,x)+f(3,4,x)+...0
where 1,2 3,4 are the first 2 sets of values from the data.
The gnuplot user-defined function sum() is set to this, and you can plot it.
If I understood correctly you are looking for something like:
with gnuplot 5.0:
gnuplot> set title "sum columns"
gnuplot> set size square
gnuplot> plot 'inputfile' u 1:($1*exp(-0.001*(x-$2)**2)) w linespoints
The output:
