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in reply to Re: How can I get the results in a text file from counting in a string?
in thread How can I get the results in a text file from counting in a string?

Good advice, definitely cleaner; ++.

But why require a second time thru each letter? Print to screen and immediately to file. For some, at least, this may rate as a minor improvement.

#!/usr/bin/perl use 5.014; # 986041 my $str="BATCATDATEFEAT"; my $A=0; my $T=0; my $output = 'D:/_Perl_/PMonks/986041.txt'; open(RESULT,">>$output") or die "Can't open $output, $!"; while ($str=~ /A/ig) { $A++; # OP's Line 4 print "\n A=$A ends at ",pos $str,"\n"; print RESULT "\n A=$A ends at ",pos $str,"\n"; } while ($str=~ /T/ig) { $T++; print "\n T=$T ends at ",pos $str,"\n"; print RESULT "\n T=$T ends at ",pos $str,"\n"; } close(RESULT); # originally, Line 17 exit; =head execution: C:\>type d:\_Perl_\PMonks\986041.txt A=1 ends at 2 A=2 ends at 5 A=3 ends at 8 A=4 ends at 13 T=1 ends at 3 T=2 ends at 6 T=3 ends at 9 T=4 ends at 14 =cut

(Perhaps obviously) console gets identical output.

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Re^3: How can I get the results in a text file from counting in a string?
by kennethk (Abbot) on Aug 07, 2012 at 20:34 UTC
    While I certainly think the code could use dramatic algorithmic improvement, I was attempting to keep the logic as consistent as possible, given the OP's apparent level of familiarity. My actual inclination would be to write it as a single pass, stashing results in a hash, so you could separate the processing and the output. Also reduces duplication of code. But to each their own, premature optimization, and all that jazz.
    #!/usr/bin/perl use 5.014; # 986041 my $str="BATCATDATEFEAT"; my $output = 'Results.txt'; open(my $fh, '>', $output) or die "Can't open $output, $!"; my %spots; while ($str =~ /([AT])/ig) { push @{$spots{uc $1}}, pos $str; } for my $key (keys %spots) { my $i = 0; for my $pos (@{$spots{$key}}) { $i++; my $text = "\n $key=$i ends at $pos\n"; print $text; print $fh $text; } } =head execution: C:\>type Results.txt A=1 ends at 2 A=2 ends at 5 A=3 ends at 8 A=4 ends at 13 T=1 ends at 3 T=2 ends at 6 T=3 ends at 9 T=4 ends at 14 =cut

    #11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.