问题
In gnuplot i can draw a rectangle via
set object rect from x0,y0 to x1,y1
How to read the coordinates x0,x1,y0,y1 from a file?
回答1:
One way would be to put the line of code that sets the rectangle into a separate file and call that file from within the gnuplot script. So you have a file called "coord.txt" that contains the one line
set object rect from 2,2 to 4,40
and you have a gnuplot script called "rect.gp" that says
set title "call rectangle coordinates"
load "coord.txt"
plot x**2
If you now from within gnuplot type load "rect.gp" you get your graph with the rectangle.
That may not be exactly what you are looking for but maybe a first step.
回答2:
You probably need to store the data from the file into variables, then use these variables to define the locations of objects. The way to do this is not straight as far as I know. Please refer to here. Good luck!
来源：https://stackoverflow.com/questions/8521824/how-to-draw-objects-rect-from-a-file