extracting value in a string after checking value after colon ':'

t-rex has asked for the wisdom of the Perl Monks concerning the following question:

Hi guys, in this forum after a long time. I have this file which gives me info like below :

available: 8 nodes (0,8,250-255)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 2
+2 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 4
+5 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 6
+8 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
node 0 size: 129733 MB
node 0 free: 125997 MB
node 8 cpus: 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 1
+05 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 12
+2 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139
+ 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 
+157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 1
+74 175
node 8 size: 129826 MB
node 8 free: 126395 MB
node 250 cpus:
node 250 size: 16128 MB
node 250 free: 16127 MB
node 251 cpus:
node 251 size: 12032 MB
node 251 free: 12031 MB
node 252 cpus:
node 252 size: 16128 MB
node 252 free: 16127 MB
node 253 cpus:
[download]

i want to extract the node number where there is nothing after the cpu colon (cpus:), example this line

node 252 cpus:
[download]

since there is nothing after the "cpus:" , i want to extract 252 from this line. I have to do this for entire file.

I wrote a regex but is not working getting me the output, pls help

here is what i wrote :

my $str = "node 250 cpus:";
#my ($a) = $str =~ /:\s*(.+)$/;
if(($str =~ /:\s*(.+)$/) eq ""){
#extract node
}
[download]

2019-01-30 Athanasius added closing code tag

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Re: extracting value in a string after checking value after colon ':'
by Athanasius (Archbishop) on Jan 30, 2019 at 06:51 UTC

Hello t-rex and welcome back!

To match a line in which nothing follows the colon (other than the terminal newline, of course), simply match on :$:

use strict;
use warnings;

while (<DATA>)
{
    print "$1\n" if / ^ node \s+ (\d+) \s+ \w+ : $ /x;
}

__DATA__
available: 8 nodes (0,8,250-255)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 2
+2 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 4
+5 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 6
+8 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
node 0 size: 129733 MB
node 0 free: 125997 MB
node 8 cpus: 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 1
+05 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 12
+2 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139
+ 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 
+157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 1
+74 175
node 8 size: 129826 MB
node 8 free: 126395 MB
node 250 cpus:
node 250 size: 16128 MB
node 250 free: 16127 MB
node 251 cpus:
node 251 size: 12032 MB
node 251 free: 12031 MB
node 252 cpus:
node 252 size: 16128 MB
node 252 free: 16127 MB
node 253 cpus:
[download]

Output:

16:43 >perl 1971_SoPW.pl
250
251
252
253

16:44 >
[download]

But if whitespace is allowed after the colon, change to:

while (<DATA>)
{
    print "$1\n" if / ^ node \s+ (\d+) \s+ \w+ : \s* $ /x;
    #                                            ^^^
}
[download]

Update: Removed unnecessary chomp from the first code block.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

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Re^2: extracting value in a string after checking value after colon ':'

by t-rex (Scribe) on Jan 30, 2019 at 08:08 UTC

Thanks

but this is not working, i get error like

Use of uninitialized value $_ in pattern match (m//) at gpu.pl line 8
[download]

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Re^3: extracting value in a string after checking value after colon ':'

by hippo (Archbishop) on Jan 30, 2019 at 09:10 UTC

You will not get that if you run the code as written, so you have changed something. Post the full code you are running as an SSCCE if you would like assistance to debug further.

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Re^3: extracting value in a string after checking value after colon ':'

by Laurent_R (Canon) on Jan 30, 2019 at 09:36 UTC

Use of uninitialized value $_

Athanasius

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Re^3: extracting value in a string after checking value after colon ':'

by t-rex (Scribe) on Jan 30, 2019 at 08:33 UTC

secondly if you see the file, there are many lines, i only want to extract the node number (250,251..) only if string cpus: is empty after the colon.

Hope i made my question clear

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Re^4: extracting value in a string after checking value after colon ':'

by Laurent_R (Canon) on Jan 30, 2019 at 09:40 UTC

Re^4: extracting value in a string after checking value after colon ':'

by poj (Abbot) on Jan 30, 2019 at 09:30 UTC

Re: extracting value in a string after checking value after colon ':'
by johngg (Canon) on Jan 30, 2019 at 17:00 UTC

You could use a negative look-ahead, i.e. only print the number from the "cpus:" line if the colon is not followed by more space-separated digits.

johngg@shiraz:~/perl/Monks$ perl -Mstrict -Mwarnings -E '
open my $inFH, q{<}, \ <<__EOD__ or die $!;
available: 8 nodes (0,8,250-255)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 2
+2 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 4
+5 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 6
+8 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
node 0 size: 129733 MB
node 0 free: 125997 MB
node 8 cpus: 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 1
+05 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 12
+2 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139
+ 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 
+157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 1
+74 175
node 8 size: 129826 MB
node 8 free: 126395 MB
node 250 cpus:
node 250 size: 16128 MB
node 250 free: 16127 MB
node 251 cpus:
node 251 size: 12032 MB
node 251 free: 12031 MB
node 252 cpus:
node 252 size: 16128 MB
node 252 free: 16127 MB
node 253 cpus:
__EOD__

while ( <$inFH> )
{
    say $1 if m{(?x) ( \d+ ) \s+ cpus: (?! \s* \d) };
}

close $inFH or die $!;'
250
251
252
253
[download]

I hope this is helpful.

Cheers,

JohnGG

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Re: extracting value in a string after checking value after colon ':'
by thanos1983 (Parson) on Jan 30, 2019 at 09:58 UTC

Hello t-rex,

Welcome back to the Monastery :)

Fellow Monks have provided you with solution(s). Just for fun a way to load multiple files:

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %hash;
my @array;
while (<>) {
    chomp;
    next unless /^node*/;  # skip lines that do not start with string 
+node
    my @tmp = split / /;
    push @array, $tmp[1];
} continue {
    close ARGV if eof;
    $hash{$ARGV} = [ @array ];
}

print Dumper \%hash;

__END__

$ perl test.pl in.txt in2.txt 
$VAR1 = {
          'in2.txt' => [
                         '0',
                         '0',
                         '0',
                         '8',
                         '8',
                         '8',
                         '250',
                         '250',
                         '250',
                         '251',
                         '251',
                         '251',
                         '252',
                         '252',
                         '252',
                         '253',
                         '0',
                         '0',
                         '0',
                         '8',
                         '8',
                         '8',
                         '250',
                         '250',
                         '250',
                         '251',
                         '251',
                         '251',
                         '252',
                         '252',
                         '252',
                         '253'
                       ],
          'in.txt' => [
                        '0',
                        '0',
                        '0',
                        '8',
                        '8',
                        '8',
                        '250',
                        '250',
                        '250',
                        '251',
                        '251',
                        '251',
                        '252',
                        '252',
                        '252',
                        '253'
                      ]
        };
[download]

Hope this helps, BR.

Seeking for Perl wisdom...on the process of learning...not there...yet!

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Re: extracting value in a string after checking value after colon ':'
by shadowsong (Pilgrim) on Jan 31, 2019 at 00:13 UTC

Hi t-rex

While there’s not much more value to be added beyond Athanasius’ response; (assuming your data resides in "file.txt") here's the obligatory one-liner:

perl -lwne "print $1 if /(\d+)\s+cpus:\s*$/" file.txt
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Best of luck
Shadowsong

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