Removing multiple blanks for a string

suppose I have a string mystr='Tom and Jerry' I want to write a function that removes all the spaces and leaves just one space in between each word. So I would want the outcome to be 'Tom and Jerry' I used mystr=mystr(~isspace(mystr)) and got TomandJerry but how would I include one space in bettween each word? Thank you

Answer 1

[the cyclist]

txt_old = 'Tom    and    Jerry';
txt_new = regexprep(txt_old,' +',' ')

See

doc regexprep

for details.

Answer 2

[Walter Roberson]

regexprep() can do that.

Hint: diff()

Answer 3

[Craig Szymanski]

A more direct andswer for anyone looking is:

function [strOut]=removeExtraSpaces(strIn);
temp2=strIn;
temp1='';

%Replaces double spaces with single spaces until the string doesn't change for an iteration.
while ~strcmp(temp1,temp2)
  temp1=temp2;
  temp2=regexprep(temp1,'  ',' ');
end

strOut=temp2;

[Ilham Hardy]

I failed to understand why is this more direct than regexprep. could explain a bit more?

[Stephen23]

Question: How are eight lines of code and a while-loop (containing strcmp and regexprep) more "direct" than one single call to regexprep?

Answer: they are not.

What this answer shows is a misunderstanding of how to use regular expressions effectively. The code uses

regexprep(temp1,'  ',' ')

to replace any doubled space characters, but this ignores the ability of regular expressions to detect any number of space characters using the regular expression ' +', as per the cyclist's solution above and also the regular expression documentation.

[Stephen23]

"Actually ...isn't working for some combination of strings. May be its a bug..."

If you upload some example strings that show this behavior then we can check this, and most likely also suggest how to deal with it efficiently (i.e. without a while loop).

"regexprep... in a loop is good workaround"

Identifying and fixing the root cause is even better.

[Tushar Walse]

Sorry my mistake. I realized the problem was when displaying strings in multiline edit box ghost spaces get displayed which I thought are coming from the output of regexprep. I may sound completely stupid sorry again. Also I deleted the comment (seems I committed another stupid mistake).