Help with awk regular expression for RS record separator

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# 8  
Old 08-08-2017
why dont you just change Mr. to Mr# using sed command then pass the file to awk command. later.. change Mr# to Mr.

can you give the sample input file and expected output file

sed 's/Mr\./Mr#/g' input | awk -F"[.!?;:]" '{do whatever...}'   | sed 's/Mr#/Mr./g'

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# 9  
Old 08-08-2017
Yes, I think that's a great idea, the input file is in my control, I could even just replace "Mr." with "Mr". Thanks for this suggestion, at least I can move on now!

The input is for a neural network, so retaining the period after the Mr is not even important and it can be discarded.

Continuing this just for academic discussion, is it not possible to do a regular expression for what I want?

thank you
# 10  
Old 08-08-2017
It's not just Mr.. It's also Mrs., Ms., Dr., Sr., Jr., and hundreds of other abbreviations. And these abbreviations don't always appear at the start of a sentence. (Or maybe you thought that the caret in (^Mr. | [?!]) means "not". It doesn't; it anchors that part of the ERE to the start of a string. And the <space> before the bracket expression is a literal <space> that must be matched exactly (and that <space> would never appear before a sentence terminating character in English text).

If your sentences all end at the end of a line, anchoring (i.e. [.!?]$ as I suggested in post #6 in this thread) should work for you. If you have multiple sentences that take multiple lines or multiple sentences on a line AND sentences that do not end at the end of a line have a sentence terminating character immediately followed by two <space> characters, then the RS value I suggested i post #6 (i.e.
RS="[.?!](  |$)"

with exactly two spaces before the vertical bar in that ERE) should give you records that are sentences (without the character that terminates the sentence).

But if you have abbreviations followed by a single space and sentence terminating characters followed by a single space (not a double space) and not appearing at the end of a line, you are going to find it very difficult to guess which periods terminate abbreviations and which periods terminate sentences. (Note that it is also possible for an abbrevition to appear at the end of a sentence.

And, semicolons and colons do not end English sentences. I don't understand why you're including them in your EREs.

Last edited by Don Cragun; 08-08-2017 at 03:53 PM.. Reason: Fix typo: s/[.!?]?/[.!?]$/
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# 11  
Old 08-08-2017
Hi Don,

Thank you for your detailed reply and examples of RS expressions.
You are correct, I would need to consider all the other abbreviations as well.

I'm using these sentences for training a neural net.

The training corpus would be classic books like Pride and Prejudice from project Gutenberg for example : Pride and Prejudice by Jane Austen - Free Ebook

Looking at this example above:

-Not all sentences end on a newline.
-There aren't two spaces after the end of a sentence
-The reason I'm considering : and ; because even though they are not complete sentences, they are in "general" complete "thoughts" and as such I can approximate them as complete sentences and reduce the complexity of the neural net.

I think the simplest solution for me seems to be to do massage the input file and do a search and replace all of the exceptions as itkamaraj suggested.

If by looking at this text example you might have another suggestion please let me know.

thank you all !
# 12  
Old 08-08-2017

If you can use perl instead of awk, see thread post 6.

Best wishes ... cheers, drl
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# 13  
Old 08-08-2017
thanks drl I will take a look
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