How can i remove a previous character present before the underscore including the underscore also.

I need to make my_john_sam as mjohsam. I need to remove underscore along with the character present just before underscore.

thanks

Answer 1

[per isakson]

Replace any one character followed by one underscore with empty string

    >> regexprep( 'my_john_sam', '._', '' )
    ans =
    mjohsam

[Sam Johnson]

Thank you...

i was doing like this

c='my_john_sam';

for i=1:length(c)

     if (strfind(c,'_'))
      x=strfind(c,'_');
           for j=1:x

               z=c(x-1:x);
               d=strrep(c,z,'');

           end

      end
  end

but i was remove only the 1st instance of underscore but not the second one.

[per isakson]

See Debug a MATLAB Program and try this

>> cssm('my_john_sam')
ans =
mjohsam
>> cssm('a string without underscore')
ans =
a string without underscore

where

function  str = cssm( str )
    ixs = strfind(str,'_');
    for jj = fliplr( ixs )
        z   = str(jj-1:jj);
        str = strrep(str,z,'');
    end
end

Answer 2

[Walter Roberson]

c='my_john_sam';
idx = c == '_';
c( idx|[idx(2:end), false]) = [];

or

c='my_john_sam';
idx = find(c == '_');
c([idx, idx-1]) = [];