Re: Re3: Regex: get first N characters but break at whitespace

Sorry if I was misleading, I was timing using a regexp vs substr to get the first 200 characters of a string.

The thing is, it doesn't matter how fast you are if you are giving the incorrect result. I was taking into account that a paragraph would have a newline on the end of each line.

original: [241] 'I need to extract the first several words from a para
+graph of text 
contained in a $var, so as to get the longest extract that's less than
+ or 
equal to 200 characters. My brute-force-and-ignorance method is: blah 
some more text here etc etc'

japhy: [66] 'I need to extract the first several words from a paragrap
+h of text'

george: [241] 'I need to extract the first several words from a paragr
+aph of text 
contained in a $var, so as to get the longest extract that's less than
+ or 
equal to 200 characters. My brute-force-and-ignorance method is: blah 
some more text here etc etc'

gav^: [194] 'I need to extract the first several words from a paragrap
+h of text contained in a $var, so as to get the longest extract that'
+s less than or equal to 200 characters. My brute-force-and-ignorance'

Hofmator: [53] 'equal to 200 characters. My brute-force-and-ignorance'
[download]

But as it turns out my code is 30 times slower than japhy's :)

gav^

Comment on Re: Re3: Regex: get first N characters but break at whitespace Download Code

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Re5: Regex: get first N characters but break at whitespace by Hofmator (Curate) on Jan 16, 2002 at 16:55 UTC
The thing is, it doesn't matter how fast you are if you are giving the incorrect result. I was taking into account that a paragraph would have a newline on the end of each line. This can be easily incorporated into the regex approaches. The problem so far is that .* doesn't match a newline. If you want that just add the /s modifier: `timethese(-3, { Hofmator => '($chunk) = substr($string,0,201) =~ /(.*\S)\s/s', japhy => '($chunk) = $string =~ /^(.{1,200})(?<!\s)(?!\w)/s;', tye => '($chunk) = $string =~ /^(.{0,199}\S)\s/s', });` [download] -- Hofmator	[reply] [d/l]

Replies are listed 'Best First'.

Re5: Regex: get first N characters but break at whitespace
by Hofmator (Curate) on Jan 16, 2002 at 16:55 UTC

The thing is, it doesn't matter how fast you are if you are giving the incorrect result. I was taking into account that a paragraph would have a newline on the end of each line.

This can be easily incorporated into the regex approaches. The problem so far is that .* doesn't match a newline. If you want that just add the /s modifier:

timethese(-3, {
    Hofmator  => '($chunk) = substr($string,0,201) =~ /(.*\S)\s/s',
    japhy     => '($chunk) = $string =~ /^(.{1,200})(?<!\s)(?!\w)/s;',
    tye       => '($chunk) = $string =~ /^(.{0,199}\S)\s/s',
});
[download]

-- Hofmator

[reply]
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