Document term frequency

[torvald_helmer]

I want to count the number of documents that contains a specified term (word)?

This is known as document frequency (DF).

 

I have an array that contains a list of txt-files. Foreach of these files I read one, and foreach of the files I read each term (word).

Inside these two loops I count how many times a term exist in one file, and I also remove multiple occurances of a term, so my result is an array of terms from a file (one occurance of each term), and an array with the number of times the word occur in the file.

 

I also want to know in how many of the total number of files each of these terms exist? Can I do this inside the loop somehow?

Or is there another smart way to solve this?

[Barand]

this may be useful

 

http://www.pgp.net/substr_count

[torvald_helmer]

It didn't work quite as I want to.

 

I have tried this, but it doesn't seem to work either:

foreach($terms as $term) { /*array of terms from one file */
	foreach($files as $file) { /*array of all files */
		if(in_array($term, $file)) {
			$DF = 'increase variable by one for each time';
		}
	}
}

[Barand]

Does the $files array contain filenames or the contents of the files?

[torvald_helmer]

$files is the list of files, I use this to make sure I go through all files.

 

$terms contain the all the words from one file