Change decimal point temporarily

lima1 has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,

I have some trouble changing the decimal point from "." to "," temporarily for parsing a CSV file. It works with:

setlocale LC_NUMERIC, "fr_FR";
#parse
....
#revert
setlocale LC_NUMERIC, "";
[download]

But this requires that "fr_FR" is installed. The localconf() function returns a nice hash, but there seems to be no counterpart for setting the locale with such a hash.

What do you recommend?

Update: Sorry, I was very unclear. Please assume I want to load a CSV (tab or semicolon separated) file and I know that the decimal point is comma. Such files are unfortunately quite common in European countries. The above code seems to work in the way that numerical columns are numeric in Perl after parsing. But it seems like a hack to hard code a temporary locale which uses a comma as decimal point.

Update 2: Problem seems to be solved Re^7: Change decimal point temporarily. There seems to be no way to avoid a regex on all fields. But can anybody explain what's happening internally here Re^6: Change decimal point temporarily? I don't quite get it... Seems more like a bug than a feature to me.

Comment on Change decimal point temporarily Download Code

Replies are listed 'Best First'.
Re: Change decimal point temporarily by ikegami (Patriarch) on Aug 02, 2010 at 20:52 UTC
`my $s = 123.45; $s =~ s/\./,/;` [download]	[reply] [d/l]
Re^2: Change decimal point temporarily by lima1 (Curate) on Aug 02, 2010 at 21:01 UTC
I was unclear. It should work automatically. With a regex, I first have to test whether it is a numeric field. Obviously, I don't want to replace points in text columns.	[reply]
Re^3: Change decimal point temporarily by ikegami (Patriarch) on Aug 02, 2010 at 22:35 UTC
`use Scalar::Util qw( looks_like_number ); my $s = 123.45; $s =~ s/\./,/ if looks_like_number($s);` [download] Works even better than setlocale because you are surely starting with the number in string form if you don't know whether a column contains a number or not.	[reply] [d/l]
Re^4: Change decimal point temporarily by Jenda (Abbot) on Aug 02, 2010 at 23:05 UTC
Re^5: Change decimal point temporarily by ikegami (Patriarch) on Aug 02, 2010 at 23:35 UTC
Some notes below your chosen depth have not been shown here
Re^3: Change decimal point temporarily by fod (Friar) on Aug 02, 2010 at 22:53 UTC
Or... I suppose if we have a digit either size of a '.' then it's probably a number with a decimal point: `$s = "123.45"; $s =~ s/(?<=\d)\.(?=\d)/,/;` [download] ALthough... I don't quite understand what you're trying to do - surely if you're parsing a CSV file containing numbers with decimal points you'd rather they weren't commas?	[reply] [d/l]
Re^4: Change decimal point temporarily by lima1 (Curate) on Aug 02, 2010 at 23:06 UTC
Re^5: Change decimal point temporarily by jeffa (Bishop) on Aug 02, 2010 at 23:30 UTC
Re: Change decimal point temporarily by nvivek (Vicar) on Aug 03, 2010 at 04:51 UTC
You can use the substitute command to do this.If you want to replace the . for only numerals.Before replacing,you can check whether that variable has numerals or not by using regular expression in substitute command as follows. `$no=123.45; $no=~s/^(\d+)\.(\d+)/$1,$2/;` [download]	[reply] [d/l]


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