replace multiple "1" with only one "1"

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Andy
Andy on 20 Apr 2014
Commented: Jan on 21 Apr 2014
first, I have a strig array with all kinds of symbols, for example:
FF1 = ('eE_?@ wwqy W');
then, I want to first turn FF2 into ASCII: FF2 =abs(FF1) . replace all the symbols with 32 ( the corresponding number for empty space). then I wanto to delete every continuous 32s into one 32. After replacement,
FF3 = ' 101 69 95 32 32 32 32 32 119 119 113 121 32 32 32 87'
the result i got should be
FF3 = ' 101 69 95 32 119 119 113 121 32 87'
this question is similar to " replace multiple space with one space", which could be done by
txt_new = regexprep(text,' +',' '). Instead, I use FF2 = regexprep(FF2, ' 32+',' 32'). But I failed.so how should I do?I attached the codes
another problem, it is only to use regexprep for str, can any function directly deal with number array?
FF2 = abs('eE_?@ wwqy W');
FF3 = num2str(FF2);
lol = regexprep(FF3, '\w*32+', ' 32');
  2 Comments
Jos (10584)
Jos (10584) on 20 Apr 2014
Your title is not matching your question ...
John D'Errico
John D'Errico on 21 Apr 2014
Andy - why flag an answer? Just add a comment if all you wanted to do was to thank a responder. Flags serve a different purpose.

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Answers (4)

Jos (10584)
Jos (10584) on 20 Apr 2014
Why not operate on the string array and then convert it to ascii? Like this:
FF1 = 'eE_?@ wwqy W'
FF3 = double(regexprep(FF1,'[^a-zA-Z0-9_]+',' '))
  3 Comments
dpb
dpb on 20 Apr 2014
Edited: dpb on 20 Apr 2014
If speed is an issue, regexp is a bottleneck, for sure...I don't believe there's any basis at all for the assumption that character substitution isn't just as fast as conversion first--after all, in Matlab they're simply an array of char() internally, anyway.
What is the problem that requires solving that the means by which one gets from FF1 to FF3 matters?
Jos (10584)
Jos (10584) on 21 Apr 2014
Apparently, you have a different problem than the one you posted here. What is it exactly you want to accomplish?

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Azzi Abdelmalek
Azzi Abdelmalek on 20 Apr 2014
FF1 = 'eE_?@ wwqy W'
FF2=abs(FF1)
FF3=FF2
a=[0 FF2==32 0];
ii1=strfind(a,[0 1])
ii2=strfind(a,[1 0])-1
FF3(cell2mat(arrayfun(@(x,y) x+1:y,ii1,ii2,'un',0)))=[]

dpb
dpb on 20 Apr 2014
I'd go at it differently, for sure...no real need for regexp() altho it'll work
>> ff3=FF1;
>> ff3(~isletter(ff3))=' ';
>> ff3=double(unique(ff3,'stable'))
ff3 =
101 69 32 119 113 121 87
>>
Looks to me like your solution missed replacing the underscore unless it's to be special-cased?
As for the question asked about dealing with it as numeric I don't see why you'd want to until the end, but unique will do the same thing there as did above.
  2 Comments
Azzi Abdelmalek
Azzi Abdelmalek on 20 Apr 2014
The expected result is
FF3 = ' 101 69 95 32 119 119 113 121 32 87'
dpb
dpb on 20 Apr 2014
Actually, though unique probably isn't the answer as it'll do the reduction globally rather than just for the blanks unless you restrict to the subset of FF3(FF3==' ')

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Azzi Abdelmalek
Azzi Abdelmalek on 20 Apr 2014
Try this
FF1 = 'eE_?@ wwqy W'
FF3=strjoin(strsplit(FF1))
  2 Comments
Azzi Abdelmalek
Azzi Abdelmalek on 21 Apr 2014
Andy, why have you flagged this answer?
Jan
Jan on 21 Apr 2014
I've removed the flag. There is obviously no reason for a flag.

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