I have a string in Perl: 'CCCCCCCC^hC^iC^*C^"C^8A'.
I want to split this string using a regular expression: "^[any_character]C". In other words, I want to split it by the actual character ^, followed by any character, followed by a specific letter (in this case C, but it could be A, or any other character).
I have tried looking at other questions/posts and finally came up with my #split_str = split(/\^(\.)C/, $letters), but this seems not to be working.
I'm sure I'm doing something wrong, but I don't know what.
You were very close. There were just a couple of errors in your code. Before I explain them, here's the code I was using to test solutions.
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
$_ = 'CCCCCCCC^hC^iC^*C^"C^8A';
my #data = split /\^(\.)C/;
say Dumper #data;
Running this with your original regex, we get this output:
$VAR1 = 'CCCCCCCC^hC^iC^*C^"C^8A';
No splitting has taken place at all. That's because your regex includes \.. The dot matches any character in a string, but by escaping it with the backslash you have told Perl to treat it as an ordinary dot. There are no dots in your string, so the regex doesn't match and the string is not split.
If we remove the backslash, we get this output:
$VAR1 = 'CCCCCCCC';
$VAR2 = 'h';
$VAR3 = '';
$VAR4 = 'i';
$VAR5 = '';
$VAR6 = '*';
$VAR7 = '';
$VAR8 = '"';
$VAR9 = '^8A';
This is better. Some splitting has taken place. But because we have parentheses around the dot ((.)), Perl has "captured" the characters that the dot matches and added them to the list of values that split() returns.
If we remove those parentheses, we get only the values between the split markers.
$VAR1 = 'CCCCCCCC';
$VAR2 = '';
$VAR3 = '';
$VAR4 = '';
$VAR5 = '^8A';
Note that we get a few empty elements. That's because in places like "^hC^iC" in your string, there is no data between two adjacent split markers.
By moving the parentheses around the whole of the regex (split /(\^.C)/), we can get a list which includes all of the split markers together with the data between them.
$VAR1 = 'CCCCCCCC';
$VAR2 = '^hC';
$VAR3 = '';
$VAR4 = '^iC';
$VAR5 = '';
$VAR6 = '^*C';
$VAR7 = '';
$VAR8 = '^"C';
$VAR9 = '^8A';
Which of these options is most useful to you depends on exactly what you're trying to do.
When you say [any_character], you must mean . pattern, a dot matches any char but linebreaks symbols, and if you use an s modifier, it will match any char.
So, in your case, you just should not have escape the dot:
#split_str = split /\^.C/, $letters;
^
Or, with an s modifier:
#split_str = split /\^.C/s, $letters;
^
The caret should be escaped to denote a literal caret symbol in a regex pattern.
There was a question regarding Counting and not Spliting.
Could be done using the regex substitution and global s//g for counting, and scalar return (the $_ contains the modified text):
my $text = 'CCCCCCCC^hC^iC^*C^"C^8C^9A^!B'; #litte longer than yours
$_ = $text ;
my $countanychar = s/\^.C//g ;
print "counting any char and C:\t $countanychar in $text\n";
$_ = $text ;
my $countnormalchar = s/\^\wC//g ; # h and i and 8 in this example avoid the * and "
print "counting normal char and C:\t $countnormalchar in $text\n";
$_ = $text ;
my $countnumber = s/\^\dC//g ;# the 8 in this example
print "counting number and C:\t $countnumber in $text\n";
$_ = $text ;
my $countextended = s/\^.\w//g ;# the he C and the A
print "counting extended C and A and B:\t $countextended in $text\n";
try like this #split_str = split(/\^/, $letters)
I'm trying to capture named groups in an array.
use strict;
use warnings;
use Data::Dumper;
my $text = 'My aunt is on vacation and eating some apples and banana';
$text =~ m/(?<Letter>A.)/img ;
print Dumper(%-) ;
output is
$VAR1 = 'Letter';
$VAR2 = [
'au'
];
but I would expect or actually was hoping that any occurrence will appear in the array.
$VAR1 = 'Letter';
$VAR2 = [
'au',
'ac',
'at',
'an',
'at',
'an'
];
Any chance to get all groups in one array?
You can either run the m//g in list context to get all the matching substrings (but without the capture names), or you need to match in a loop:
my #matches = $text =~ m/(?<Letter>A.)/img ;
print Dumper(\#matches) ;
or
while ($text =~ m/(?<Letter>A.)/img) {
print Dumper(\%+) ;
}
I am trying to match a word that starts with a letter and is followed by at .
I use this regex for it
use strict;
use warnings;
use Data::Dumper;
my $str = "fat 123 cat sat on the mat";
my #a = $str =~ /(\s?[a-z]{1,2}(at)\s?)/g;
print Dumper( #a );
the out put I am getting is:
$ perl ~/playground/regex.pl
$VAR1 = 'fat ';
$VAR2 = 'at';
$VAR3 = ' cat ';
$VAR4 = 'at';
$VAR5 = 'sat ';
$VAR6 = 'at';
$VAR7 = ' mat';
$VAR8 = 'at';
why does it match "at" as well when I clearly say match just 1 character before at.
Your optional spaces aren't a good way to delimit words: they are optional
Use the word boundary construct \b for a rough match to the ends of words
use strict;
use warnings;
use Data::Dumper;
my $str = "fat 123 cat sat on the mat";
my #aa = $str =~ /\b[a-z]+at\b/gi;
print Dumper \#aa;
output
$VAR1 = [
'fat',
'cat',
'sat',
'mat'
];
If you want to be more clever and be certain that the word found isn't preceded or followed by a non-space character then you can write this instead
my #aa = $str =~ /(?<!\S)[a-z]+at(?!\S)/gi;
which produces the same result for the data you show
I have a string in Perl: 'CCCCCCCC^hC^iC^*C^"C^8A'.
I want to split this string using a regular expression: "^[any_character]C". In other words, I want to split it by the actual character ^, followed by any character, followed by a specific letter (in this case C, but it could be A, or any other character).
I have tried looking at other questions/posts and finally came up with my #split_str = split(/\^(\.)C/, $letters), but this seems not to be working.
I'm sure I'm doing something wrong, but I don't know what.
You were very close. There were just a couple of errors in your code. Before I explain them, here's the code I was using to test solutions.
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
$_ = 'CCCCCCCC^hC^iC^*C^"C^8A';
my #data = split /\^(\.)C/;
say Dumper #data;
Running this with your original regex, we get this output:
$VAR1 = 'CCCCCCCC^hC^iC^*C^"C^8A';
No splitting has taken place at all. That's because your regex includes \.. The dot matches any character in a string, but by escaping it with the backslash you have told Perl to treat it as an ordinary dot. There are no dots in your string, so the regex doesn't match and the string is not split.
If we remove the backslash, we get this output:
$VAR1 = 'CCCCCCCC';
$VAR2 = 'h';
$VAR3 = '';
$VAR4 = 'i';
$VAR5 = '';
$VAR6 = '*';
$VAR7 = '';
$VAR8 = '"';
$VAR9 = '^8A';
This is better. Some splitting has taken place. But because we have parentheses around the dot ((.)), Perl has "captured" the characters that the dot matches and added them to the list of values that split() returns.
If we remove those parentheses, we get only the values between the split markers.
$VAR1 = 'CCCCCCCC';
$VAR2 = '';
$VAR3 = '';
$VAR4 = '';
$VAR5 = '^8A';
Note that we get a few empty elements. That's because in places like "^hC^iC" in your string, there is no data between two adjacent split markers.
By moving the parentheses around the whole of the regex (split /(\^.C)/), we can get a list which includes all of the split markers together with the data between them.
$VAR1 = 'CCCCCCCC';
$VAR2 = '^hC';
$VAR3 = '';
$VAR4 = '^iC';
$VAR5 = '';
$VAR6 = '^*C';
$VAR7 = '';
$VAR8 = '^"C';
$VAR9 = '^8A';
Which of these options is most useful to you depends on exactly what you're trying to do.
When you say [any_character], you must mean . pattern, a dot matches any char but linebreaks symbols, and if you use an s modifier, it will match any char.
So, in your case, you just should not have escape the dot:
#split_str = split /\^.C/, $letters;
^
Or, with an s modifier:
#split_str = split /\^.C/s, $letters;
^
The caret should be escaped to denote a literal caret symbol in a regex pattern.
There was a question regarding Counting and not Spliting.
Could be done using the regex substitution and global s//g for counting, and scalar return (the $_ contains the modified text):
my $text = 'CCCCCCCC^hC^iC^*C^"C^8C^9A^!B'; #litte longer than yours
$_ = $text ;
my $countanychar = s/\^.C//g ;
print "counting any char and C:\t $countanychar in $text\n";
$_ = $text ;
my $countnormalchar = s/\^\wC//g ; # h and i and 8 in this example avoid the * and "
print "counting normal char and C:\t $countnormalchar in $text\n";
$_ = $text ;
my $countnumber = s/\^\dC//g ;# the 8 in this example
print "counting number and C:\t $countnumber in $text\n";
$_ = $text ;
my $countextended = s/\^.\w//g ;# the he C and the A
print "counting extended C and A and B:\t $countextended in $text\n";
try like this #split_str = split(/\^/, $letters)
Have this string:
ABC,-0.5,10Y,10Y,['TEST'],ABC.1000145721ABC,-0.5,20Y,10Y,['TEST'],ABC.1000145722
The data is repeated.
I need to remove the []' characters from the data so it looks like this:
ABC,-0.5,10Y,10Y,TEST,ABC.1000145721ABC,-0.5,20Y,10Y,TEST,ABC.1000145722
I'm also trying to split the data to assign it to variables as seen below:
my($currency, $strike, $tenor, $tenor2,$ado_symbol) = split /,/, $_;
This works for everything but the ['TEST'] section. Should I remove the []' characters first then keep my split the same or is there an easier way to do this?
Thanks
Something that's useful to know is this - that split takes a regex. (It'll even let you capture, but that'll insert into the returned list, which is why I've got (?: for non capturing groups)
I observe your data only has [' right next to the delimiter - so how about:
#!/usr/bin/env perl
use strict;
use warnings;
use Data::Dumper;
while ( <DATA> ) {
chomp;
my #fields = split /(?:\'])?,(?:\[\')?/;
print Dumper \#fields;
}
__DATA__
ABC,-0.5,10Y,10Y,['TEST'],ABC.1000145721ABC,-0.5,20Y,10Y,['TEST'],ABC.1000145722
Output:
$VAR1 = [
'ABC',
'-0.5',
'10Y',
'10Y',
'TEST',
'ABC.1000145721ABC',
'-0.5',
'20Y',
'10Y',
'TEST',
'ABC.1000145722'
];
my $str = "ABC,-0.5,10Y,10Y,['TEST'],ABC.1000145721ABC,-0.5,20Y,10Y,['TEST'],ABC.1000145722";
$str =~ s/\['|'\]//g;
print $str;
output is
ABC,-0.5,10Y,10Y,TEST,ABC.1000145721ABC,-0.5,20Y,10Y,TEST,ABC.1000145722
Now you can split.
Clean up $ado_symbol after split:
$ado_symbol =~ s/^\['//;
$ado_symbol =~ s/'\]$//;
You can use a global regex match to find all substrings that are not a comma, a single quote, or a square bracket
Like this
use strict;
use warnings 'all';
my $s = q{ABC,-0.5,10Y,10Y,['TEST'],ABC.1000145721ABC,-0.5,20Y,10Y,['TEST'],ABC.1000145722};
my #data = $s =~ /[^,'\[\]]+/g;
my ( $currency, $strike, $tenor, $tenor2, $ado_symbol ) = #data;
print "\$currency = $currency\n";
print "\$strike = $strike\n";
print "\$tenor = $tenor\n";
print "\$tenor2 = $tenor2\n";
print "\$ado_symbol = $ado_symbol\n";
output
$currency = ABC
$strike = -0.5
$tenor = 10Y
$tenor2 = 10Y
$ado_symbol = TEST
Another alternative
my $str = "ABC,-0.5,10Y,10Y,['TEST'],ABC.1000145721ABC,-0.5,20Y,10Y,['TEST'],ABC.1000145722";
my ($currency, $strike, $tenor, $tenor2,$ado_symbol) = map{ s/[^A-Z0-9\.-]//g; $_} split ',',$str;
print "$currency, $strike, $tenor, $tenor2, $ado_symbol",$/;
Output is:
ABC, -0.5, 10Y, 10Y, TEST