Re: Substring comparison

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Re^2: Substring comparison by flaviodesousa (Initiate) on May 01, 2012 at 15:55 UTC
As trammell pointed out index() returns 0 if the sought for string is the beginning. Try this: `@Array1 = qw{XXX FFF ZZZ AAA BBB QQQ LLL JKK III CCC DDD DCD}; @Array2 = ("XXX BBB AAA CCC DDD EEE", "FFF NNN JKK III LLL QQQ"); foreach(@Array1) { $string1 = $_; foreach(@Array2) { my $string2 = $_; my $result = index($string2, $string1); print $string1, ($result >= 0 ? " IS " : " IS NOT", + " found in "), $string2, "\n"; } }` [download]	[reply] [d/l]
Re^2: Substring comparison by schtinkfist893 (Novice) on May 01, 2012 at 16:25 UTC
Excellent! flaviodesousa solution works for explicitly defined arrays my @Array1 = qw{XXX FFF ZZZ AAA BBB QQQ LLL JKK III CCC DDD DCD}; my @Array2 = ("XXX BBB AAA CCC DDD EEE", "FFF NNN JKK III LLL QQQ"); XXX IS found in XXX BBB AAA CCC DDD EEE XXX IS NOT found in FFF NNN JKK III LLL QQQ FFF IS NOT found in XXX BBB AAA CCC DDD EEE FFF IS found in FFF NNN JKK III LLL QQQ However my arrays are being read in from a text file `my $file1 = '/tmp/file1.txt'; my @Array1; open FILE, $file1 or die $!; while(<FILE>) { @Array1 = <FILE>; } my $file2 = '/tmp/file2.txt'; my @Array2; open FILE, $file2 or die$!; while(<FILE>) { @Array2 = <FILE>; } print @Array1; Print @Array2;` [download] /tmp/file1.txt is as stated above `XXX FFF ZZZ AAA BBB QQQ LLL JKK III CCC DDD DCD` [download] /tmp/file2.txt is `XXX BBB AAA CCC DDD EEE FFF NNN JKK III LLL QQQ` [download] This outputs `FFF ZZZ AAA BBB QQQ LLL JKK III CCC DDD DCD FFF NNN JKK III LLL QQQ` [download] So it looks the method I am reading in the Arrays is not as thorough as I expect it to be.	[reply] [d/l] [select]
Re^3: Substring comparison by johngg (Canon) on May 01, 2012 at 21:31 UTC
`while(<FILE>) { @Array1 = <FILE>; }` [download] That is not going to do quite what you'd hoped. The first time into the loop it will read the first line of the file into the `$_` variable, which you never use so that line will be lost. Then, inside the loop you read the file handle in list context as you have an array on the LHS. That will have the effect of reading the remaining lines of the file, one line per element, into the array; the the loop will exit on the next iteration as EOF has been reached. Your array will contain all lines but the first. As you've discovered in your subsequent post you will have to chomp to get rid of line terminators. The correct way to populate your array in a loop would be to use push. `my @arr; while ( <$fh> ) { chomp; push @arr, $_; }` [download] However, there is an easier way as chomp will also operate on arrays `my @arr = <$fh>; chomp @arr;` [download] or even `chomp( my @arr = <$fh> );` [download] I hope this is helpful. Cheers, JohnGG	[reply] [d/l] [select]