Counting lines when reading a file

[kiffab]

Hi

I'm trying to address an issue with slow performance on an app I'm creating.

I'm reading a file and writing to another file. I want to keep track of the number of entries by counting. I think my counts may be what's slowing things down here. The count may only be 100 or so but it still takes quite a while.

Any tips on optimising to speed things up? (I just output my counts by updating a label on a GUI).

I'm not much of a coder, just trying to cobble something together for work!

Thanks

$exists = 0
$notexists = 0
$total = 0

While 1
    $line_read = FileReadLine($handle_read)

    If @error Then ExitLoop

    If Not FileExists($line_read) Then

        FileWriteLine($handle_write, $line_read & ' does not exist!' @CRLF)

        $notexists = $notexists + 1 

    ElseIf FileExists($line_read) Then

        FileWriteLine($handle_write, $line_read & ' exists!' @CRLF)

        $exists = $exists+1

    EndIf
WEnd

$total = $exists + $notexists

Edited August 4, 2011 by kiffab

[guinness]

Why not read the file to an Array using _FileReadToArray(), see the Help file for more details.

[kiffab]

Thanks

[guinness]

You're welcome.

[Mobius]

Hi kiffab,

In your original source every file that does exist would be checked on the disk for twice, which might slow it up a little.

how about something like this:

$exists = 0
$notexists = 0
$total = 0

While 1
    $line_read = FileReadLine($handle_read)

    If @error Then ExitLoop

    If FileExists($line_read) Then

        FileWriteLine($handle_write, $line_read & ' exists!' @CRLF)

        $exists += 1

    Else

        FileWriteLine($handle_write, $line_read & ' does not exist!' @CRLF)

        $notexists += 1

    EndIf
WEnd

$total = $exists + $notexists

Edited August 4, 2011 by Mobius

[Tvern]

Mobius beat me to it. The second FileExists is unneeded and takes allot more time that a simple counter.

Another thing that might take some extra time are all the single line writes for each file, so you could instead write all lines at once when you are done like this:

Global $sFilePath, $handle_write

Global $aFile, $sOutFile
_FileReadToArray($sFilePath,$aFile)
Global $iExists = 0, $iNoExist = 0, $iTotal = $aFile[0]
For $i = 1 To $aFile
    If FileExists($aFile[$i]) Then
        $sOutFile &= $aFile[$i] & ' exists!' & @CRLF
        $iExists += 1
    Else
        $sOutFile &= $aFile[$i] & ' does not exist!' & @CRLF
        $iNoExist += 1
    EndIf
Next
FileWrite($handle_write, $sOutFile) ;You could at this point strip the last @CRLF if it bothers you.