rename files from alpha to numeric

[jfix]

hello,

I have files whose names start with "parta...." which I'd like to
rename to "n0001..." where the "a" is transformed to 1, the "b" to 2
etc. I'm pretty sure there's an easy way where you take the
character's ascii value and substract the difference plus one (like
this: asc("a") - 96 = 1, right?)

sub renameFiles {
my %part = {'a' => 1, "b" => 2, "c" => 3,
"d" => 4, "e" => 5, "f" => 6};

foreach $f (@filelist) {
$f =~ s{ ### complains about Uninitialised
### value in this line
^part(.)
}{
sprintf("n%03d", $part{$1});
}xeg;
print "$f\n";
}
}

I guess this is way too much, and it is very slow (probably evaluating
the Perl code for each match), but this is my stab, and it doesn't even
work and I don't even know why.

thanks for any help,
Jakob.

 

[Jim Keenan]

hello,

I have files whose names start with "parta...." which I'd like to
rename to "n0001..." where the "a" is transformed to 1, the "b" to 2
etc. I'm pretty sure there's an easy way where you take the
character's ascii value and substract the difference plus one (like
this: asc("a") - 96 = 1, right?)

sub renameFiles {
my %part = {'a' => 1, "b" => 2, "c" => 3,
"d" => 4, "e" => 5, "f" => 6};

foreach $f (@filelist) {
$f =~ s{ ### complains about Uninitialised
### value in this line
^part(.)
}{
sprintf("n%03d", $part{$1});
}xeg;
print "$f\n";
}
}

I guess this is way too much, and it is very slow (probably evaluating
the Perl code for each match), but this is my stab, and it doesn't even
work and I don't even know why.

Assuming that by "it doesn't even work" you mean that no files are
renamed, I am not surprised. Nothing in the code excerpt you presented
renames a file; it merely prints something to STDOUT.

Check out the documentation: perldoc -f rename

Jim Keenan

 

[Gunnar Hjalmarsson]

I have files whose names start with "parta...." which I'd like to
rename to "n0001..." where the "a" is transformed to 1, the "b" to 2
etc. I'm pretty sure there's an easy way where you take the
character's ascii value and substract the difference plus one (like
this: asc("a") - 96 = 1, right?)

s/^part(\w)/sprintf 'n%03d', ord($1)-96/e for @filelist;

 

[A. Sinan Unur]

hello,

I have files whose names start with "parta...." which I'd like to
rename to "n0001..." where the "a" is transformed to 1, the "b" to 2
etc. I'm pretty sure there's an easy way where you take the
character's ascii value and substract the difference plus one (like
this: asc("a") - 96 = 1, right?)

#! /usr/bin/perl

use strict;
use warnings;

while(<DATA>) {
if(/^part([a-z])/) {
printf "n%4.4d\n", ord($1) - ord('a') + 1;
}
}

__END__
parta
partc
partd
parte
partb
partv
partz

D:\Home\asu1\UseNet\clpmisc> ttt
n0001
n0003
n0004
n0005
n0002
n0022
n0026

 

[jfix]

Thanks everybody who replied to me. That was exactly what I needed.

cheers,
Jakob.