regular expressions in bash

[cwl157]

I need to write a program that will take an x and y pair and extract out what x is equal to and what y is equal to. The pair can be entered in many different ways. A few ways include:

x=2.0 y=2.3
y=4.3 x=1.8
or
x = 2.0 y = 2.3
y = 4.3 x = 1.8
or
x = 20; y = -30
y = -5.3; x = 7.8
or
x -4.5 y -5.89
Basically any combo you can think of x first, y first, space seperating, comma seperating semi colon seperating, space in between the = sign, no space in between = sign, no equal sign, negative numbers, positive numbers, integers, floating point numbers, if both x and y are the same it can be written as
x=y=1.0
y=x=1.20
I think this can be done with regular expressions and grep, egrep, awk, sed, even though i don't understand any of those, nor do i understand any of the man pages for those either, but i think those are what i need to use. Anyone have any ideas of how to take the input entered like the above examples and get what the x is equal to and what the y is equal to from it?

[ghostdog74]

I think this can be done with regular expressions and grep, egrep, awk, sed, even though i don't understand any of those, nor do i understand any of the man pages for those either, but i think those are what i need to use.

why didn't you try to learn how to use them then? at least try to come up with something.

[sangoma23]

I guess something like this would work although I'm not the best perl scripter and there's probably lots to go wrong.

#!/usr/bin/perl

$i = 1;
while(<>){
print "Line: $i\n";
if(/x( ?= ?)?(-?[0-9]+(\.[0-9]+)?)/){
$x = $2; print "x = $x ";
if(/^y( ?= ?)x/){
$y = $x; print "y = $x";
}
}
if(/y( ?= ?)?(-?[0-9]+(\.[0-9]+)?)/){
$y = $2; print "y = $y ";
if(/^x( ?= ?)y/){
$x = $y; print "x = $y";
}
}
print "\n";
$i = $i + 1;
}