Shell Programming and Scripting

Hi everyone,

I need very simple sed command to change a parameter in a text file.

I have a line in this text which is like

Code:

set xx 0.5

A program reads this file and does some algebraic calculations. So to make a parameter scan I need to change the value of xx. I thought I can do this with a simple sed command in a shell loop. so the shell simply will look like

Code:

#!/bin/sh
xx=0.0
for ((i=0; i<=10; i++))
do xx = xx + i*0.5

% here comes the sed command which substitutes the existing value of xx with the one set above, and afterwards runs the program which reads that text file

done

thanks for all the help