I've just started to learning perl and decided to write up a script to add vectors for my silly Physics class. I've gotten maybe halfway through it, and I am confounded by errors.

My program opens a file 'vectors' which contains 4 numbers, which are then assigned to variables using split(); The errors I am getting involve the use of unitialized variables so I think my use of split() is to blame.

Here's the script:

#!/usr/bin/perl -w

$foo = 0;

open (VECTORS, "vectors") or die print "Cannot open 'vectors' file: $!
+\n";

while ($line = <VECTORS>) {
    if ($line =~ /\d/) {
    chomp $line;
    ($vectorA[$foo], $angleA[$foo], $vectorB[$foo], $angleB[$foo]) = s
+plit " ", $line, 4;
    ++$foo;
    }
}


$max_vectors = $foo;

for ($foo = 0; $foo <= $max_vectors; ++$foo) { 
    $X[$foo] += ($vectorA[$foo] * cos($angleA[$foo]));
    $X[$foo] += ($vectorB[$foo] * cos($angleB[$foo]));
}

for ($foo = 0; $foo <= $max_vectors; ++$foo) { 
    $Y[$foo] += ($vectorA[$foo] * sin($angleA[$foo]));
    $Y[$foo] += ($vectorB[$foo] * sin($angleB[$foo]));
}

# Must do more stuff here, ie. finish and convert to degrees after sin
+() and cos()

foreach $X (@X) {
    print "$X\n";
}

print "\nblah\n\n";

foreach $Y (@Y) {
    print "$Y\n";
}
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Vector Addition File
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