little algorithm help

Creamy Goodness · 04-07-2008 07:48AM #1

i have a text file that's comma delimited that i need to process.

the structure of the file is like so...

feature | label | date |number of people | preptime | majorfaults | minorfaults
feature1,label1,,13/06/2008,5,5,2,4
feature1,label3,,...................,5,4,6

and so on

what i want to be able to do is to sum up the majorfaults and minor faults for each feature.

so in this case i want the sumMajors to be 6 and the sumMinors to be 10.

there are hundreads of features in this text file.

i'm using perl for this by the way here's what i have so far.

[php]
//open the file
open ("FILE", "file.txt");
my @file = <FILE>;

my $prevFeature = "";
my $sumMajors;
my $sumMinors;

foreach my $line(@file)
{
($feature,$label,$date,$people,$prepTime, $majors, $minors) = split(",",$line);

//check to see if the feature is equal to previous feature.
if($prevFeature eq $feature)
{
//sum them up
$sumMajors += $majors ;
$sumMinors += $minors ;
}
else
{
//reset the sum values
$sumMajors = 0 ;
$sumMinors = 0 ;
}

//i print out the results here.
print "sumMajors: " . $sumMajors . "\n" ;
print "sumMinors: " . $sumMinors . "\n" ;

//make the prevFeature equal to the current feature for the next check.
$prevFeature = $feature;

[/php]

but what i get is the total being +1 of what it should be.

i think the algorithm is correct but then again it can't be

sham08 · 04-07-2008 08:09AM

Cremo wrote: »

($feature,$label,$date,$people,$prepTime, $majors, $minors) = split(",",$line);

are you missing $product? Sorry haven't done perl so I'm not sure of the convention

Creamy Goodness · 04-07-2008 08:13AM

sham08 wrote: »

are you missing $product? Sorry haven't done perl so I'm not sure of the convention

whoops sorry product isn't contained in the file, i had to type that bit out as for some reason my copy and paste isn't working atm

i've edited the OP.

dazberry · 04-07-2008 08:17AM

Not sure, but what I did notice was that I think you'll need to change the "summing" code as follows:

      if($prevFeature eq $feature)
      {
             //sum them up
             $sumMajors += $majors ; 
             $sumMinors += $minors ;
      }
      else
      {
             //reset to current line values
             $sumMajors = $majors ; 
             $sumMinors = $minors ;
      }

as it looks to me that you'll drop the major and minor fault values of the current line if the feature changes. I don't know if you'll need to specifically set the sum*** variable to 0 prior to the loop or if they're already initiated to 0 in Perl by default.

D.

Creamy Goodness · 04-07-2008 01:12PM

Perfect Daz,

that worked. I knew it had to of been something simple. I was writing that last night still in work at 8:30 last night

little algorithm help

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