How can I convert a string to a number in Perl?

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I have a string which holds a decimal value in it and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string to an integer.

9 Answers

You don't need to convert it at all:

% perl -e 'print "5.45" + 0.1;'
5.55

Perl is a context-based language. It doesn't do its work according to the data you give it. Instead, it figures out how to treat the data based on the operators you use and the context in which you use them. If you do numbers sorts of things, you get numbers:

# numeric addition with strings:
my $sum = '5.45' + '0.01'; # 5.46

If you do strings sorts of things, you get strings:

# string replication with numbers:
my $string = ( 45/2 ) x 4; # "22.522.522.522.5"

Perl mostly figures out what to do and it's mostly right. Another way of saying the same thing is that Perl cares more about the verbs than it does the nouns.

Are you trying to do something and it isn't working?

Perl really only has three types: scalars, arrays, and hashes. And even that distinction is arguable. ;) The way each variable is treated depends on what you do with it:

% perl -e "print 5.4 . 3.4;"
5.43.4


% perl -e "print '5.4' + '3.4';"
8.8
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