how to define the occurance of a word in a text?

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Hi all,I need that code badly,I have a text'.txt'.I have chosen two words"are" and "the" which are repeated along the text so I need a code to read the text and if the word "are" comes put "1" and if the word "the" comes put "0" sequentially so a series of binary digits"x" is formed. for example x=1 0 0 1 1 1 1 0 that means "are" occurs first then "the"occurs twice then"are" four times then"the" and so on until the text ends.thanks
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Walter Roberson
Walter Roberson on 30 Jul 2017
So not counted if there is a comma, period, exclamation mark, colon, semi-colon, apostrophe or double quote or other quote marks?
jojototo
jojototo on 31 Jul 2017
Oh my god,I didn't think about all these possibilities .You're absolutely right all these are counted of course.

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Accepted Answer

Walter Roberson
Walter Roberson on 30 Jul 2017
whichone = strcmp('and', lower(regexp(str, '(?<=^| )(([tT]he)|([aA]nd))(?=$| )', 'match')));
whichone is 1 for each occurrence of 'and' and 0 for each occurrence of 'the'
  4 Comments
Walter Roberson
Walter Roberson on 9 Aug 2017
Break it up into pieces.
thes = regexp(str, '(?<=^|["'' ])([tT]he ?)(?=$|[,.!:;"'' ])');
this finds "the" or "The" that are preceded by beginning of line or by a space or double quote or apostrophe, and which might be followed by a space, and after that followed by a comma, period, exclamation mark, colon, semi-colon, double-quote, apostrophe, or space. The "the" or "The" and the possible space are extracted, but not what follows that.
Once you have these, you can tell the cases apart by various ways, including comparing the last character to a space, or just looking at the length:
cellfun(@length, thes)
length 3 has no space after it, length 4 had a space after it.
Unfortunately, though, you have an ambiguous situation. At the end of the line, you cannot tell whether "the" followed by space followed by end of line is the "normal" case or the "extra space" case. This code will detect it as if it is the "extra space" case, but that is arguably wrong: it could instead be a "normal space" that happens to be followed by nothing.
As I wrote before, "Rules! We need rules!" -- and those rules need to define what the "correct" outcome is in each potentially ambiguous situation.

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