To convert a fraction to decimal equivalent (or approximation, if the fraction doesn't divide out cleanly): 
if ($fraction =~ /^((-) ?)?((\d+) )?(\d+) ?\/ ?(\d+)$/) {
    $fraction = ($2 ? -1 : 1) * ($4 + $5 / $6); 
}

[download]
To test for a negative: 
if ($fraction =~ /^((-) ?)?((\d+) )?(\d+) ?\/ ?(\d+)$/ && $2) {
    #run if negative...
}

[download]

In reply to Re: How do I detect if a number has a minus sign? by TedPride
in thread How do I detect if a number has a minus sign? by algonquin

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