Need help with string counting

Hello. I have problem with counting string.

First of all, I need to count how many i have letters in word (using this):

prompt='Iveskite raide/zodi-';
str=input(prompt,'s');

gauto_zodio_ilgis=length(str);

Second, I write to command window LABAS

My all arrays:

My code:

dydis=0;

prompt='Iveskite raide/zodi-';
str=input(prompt,'s');

gauto_zodio_ilgis=length(str);

  
% for sk=1:gauto_zodio_ilgis

    if strfind(str,'A') 
        
        dydis = dydis + length(A);
    end

    if strfind(str,'B') 
        
        dydis = dydis + length(B);
    end
    if strfind(str,'C') 
        
        dydis = dydis + length(C);
    end
    if strfind(str,'D') 
        
        dydis = dydis + length(D);
    end
    if strfind(str,'E') 
        
        dydis = dydis + length(E);
    end
    if strfind(str,'F') 
        
        dydis = dydis + length(F);
    end
    if strfind(str,'G') 
        
        dydis = dydis + length(G);
    end
    if strfind(str,'H') 
        
        dydis = dydis + length(H);
    end
    if strfind(str,'I') 
        
        dydis = dydis + length(I);
    end
    if strfind(str,'J') 
        
        dydis = dydis + length(J);
    end
    if strfind(str,'K') 
        
        dydis = dydis + length(K);
    end
    if strfind(str,'L') 
        
        dydis = dydis + length(L);
    end
    if strfind(str,'M') 
        
        dydis = dydis + length(M);
    end
    if strfind(str,'N') 
        
        dydis = dydis + length(N);
    end
    if strfind(str,'O') 
        
        dydis = dydis + length(O);
    end
    if strfind(str,'P') 
        
        dydis = dydis + length(P);
    end
    if strfind(str,'Q') 
        
        dydis = dydis + length(Q);
    end
    if strfind(str,'R') 
        
        dydis = dydis + length(R);
    end
    if strfind(str,'S') 
        
        dydis = dydis + length(S);
    end
    if strfind(str,'T') 
        
        dydis = dydis + length(T);
    end
    if strfind(str,'U') 
        
        dydis = dydis + length(U);
    end
    if strfind(str,'V') 
        
        dydis = dydis + length(V);
    end
    if strfind(str,'W') 
        
        dydis = dydis + length(W);
    end
    if strfind(str,'X') 
        
        dydis = dydis + length(X);
    end
    if strfind(str,'Y') 
        
        dydis = dydis + length(Y);
    end
    if strfind(str,'Z') 
        
        dydis = dydis + length(Z);
    end

I get answer dydis = 140000, but by my counting I have to get 165000

HOW TO I NEED TO CHANGE MY CODE???

Thanks for any help

[Stephen23]

You should read this:

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

and then follow KSSV's advice.

Or use a table.

Or a structure.

Whatever you do, do NOT write slow, complex, buggy code using evil eval.

Answer 1

[Jamuna]

update your code of if statements with

for ii=1:26

if strfind(str,char(ii+64))

dydis = dydis + length(eval(char(ii+64)))*numel(strfind(str,char(ii+64)));

end

end

this should give you right answer

[Stephen23]

Or write simpler and more efficient code which avoids evil eval entirely, such as that shown by KSSV here:

https://www.mathworks.com/matlabcentral/answers/508933-need-help-with-string-counting#answer_418444

[Ricardas Gudonavicius]

THANKS

Answer 2

[KSSV]

You have made your code very lengthy......you should follow like this.

S = {'A','B',.....'Z'} ;  % write all the letters 
dydis=0;
for i = 1:length(S)
    W = strfind(str,S{i}) ;
    dydis = dydis + length(W);
end

[Ricardas Gudonavicius]

THANKS

Answer 3

[Constantino Carlos Reyes-Aldasoro]

Perhaps the error is here:

    if strfind(str,'A') 
        
        dydis = dydis + length(A);
    end

You are detecting the character 'A' but then you are finding the length of a variable called 'A'. Try like this

    A_inString = strfind(str,'A');
    if  ~isempty(A_inString)       
        dydis = dydis + length(A_inString);
    end

You save the output of the find in a variable, and then if it is not empty, then you add the length of the strfind.

Hope this helps. If this solves the problem, please accept the answer. If not, let me know.

[Ricardas Gudonavicius]

THANKS