hello friends, see I am executing a simple code . I want your little help in it.

close all;
clear all;
clc;
str=('ttttttPttttPPttt');

estring(str)
-----------------------------------------function estring--------------------------------

    function estring(str)
    len = numel(str);
    i = 0;
    count = zeros(1,len);
    while( i<len )
        j=0;
        count(i+1) = 1;
        while( true )
            j = j + 1;
            if( i+j+1 > len )
                break;
            end
            if( str(i+j+1)==str(i+1) )
                count(i+1) = count(i+1) + 1;

            else
                break;
            end
        end
        if( count(i+1)==1 )
            a=str(i+1);
            length(a);
            fprintf('%c',a); 

            i = i + 1;

        else
            a=str(i+1);
            b=count(i+1);
            fprintf('%c%d',a,b);

            i = i + b;

        end

    end

    fprintf('\n');

    end

this is giving output as t6Pt4P2t3. *I want estring to return the output to script. e.g

y=estring(str) in the script

function a=estring(str)

It is not working. Please suggest me how to do this.

Answer 1

[Geoff Hayes]

Tina - if you want your function to return a string (rather than writing it to the Command Window with fprintf) the first thing you have to do is change your function signature to return an output value

 function [estr] = estring(str)

 % initialize estr
 estr = '';

Now replace all of your fprintf calls with code that will concatenate the estr with the new data. For example,

 fprintf('%c',a);

becomes

 estr = [estr a];

and

 fprintf('%c%d',a,b);

becomes

 estr = [estr a num2str(b)];

Try implementing the above and see what happens!

Answer 2

[Radha Krishna Maddukuri]

Hello Tina,

In the function that you have written, you are printing out values, rather you have to assign it to a variable. I have changed your code a bit:

function  y = estring(str)
len = numel(str);
i = 0;
count = zeros(1,len);
y=[];
while( i<len )
  j=0;
  count(i+1) = 1;
  while( true )
      j = j + 1;
      if( i+j+1 > len )
          break;
      end
      if( str(i+j+1)==str(i+1) )
          count(i+1) = count(i+1) + 1;
      else
          break;
      end
  end

    if( count(i+1)==1 )
        a=str(i+1);
        length(a);
        y = [y a];
        i = i + 1;
    else
        a=str(i+1);
        b=count(i+1);
        y =[y a num2str(b)];
        i = i + b;
    end
end
end

From this function, when you execute the following command:

>> y = estring(str)

It will work.