MATLAB loop with different value

Question

I have two different function that send a value to another. My problem is that the random value that is given is same too all parameter.

This is my test_main function

function[] = test_main(x)

for i = 1:x %loop for time

w=rand; %random error generator. 
    if w<0.5 
        status=1;
    else
        status=99; 
    end

fprintf('\n Time is %d hour after count start .  \n', i);

test_sub(status);


end
end

This is my test_sub function

function[a] = test_sub(z)

for variable = 1:4
    fprintf('\nPARAMETER %d ', variable)


fprintf('\n Value is %d \n', z);

if (z==1) %if input equal to 0
   j=1; %store temporary value to j
   a=j; 
   disp('new value is 1')

elseif (z==99)
   j=1;
   a=j;
   disp('new value is 100')

else
   disp('unidentified error')
end

end
end

The code has no error only the looping part is not working. The output from both function is above:

Time is 1 hour after count start .  

PARAMETER 1 
 Value is 99 
new value is 100

PARAMETER 2 
 Value is 99 
new value is 100

PARAMETER 3 
 Value is 99 
new value is 100

PARAMETER 4 
 Value is 99 
new value is 100

The integer that was assigned to "value" is the same on all four parameter. I was hoping that each parameter will have different value and it will come out sort of like this:

Time is 1 hour after count start .  

PARAMETER 1 
 Value is 1 
new value is 1

PARAMETER 2 
 Value is 1 
new value is 1

PARAMETER 3 
 Value is 99 
new value is 100

PARAMETER 4 
 Value is 1 
new value is 1

Answer 1

Do you realize you are doing the same thing 4 times? That is why you dont get new values, there are not.

You code does:

• test_main(1) I assume 1, or else you are not showing all the outputs.
• create random w
• if w<0.5 ...

• call test_sub(status)

  • Here, the first thing is for variable = 1:4 , or "repeat everything 4 times"
  • repeats disp 4 times for the same status
  • out.

Why do you have the for loop inside the test_sub function? The function is supposed to test the result, and should only do that. It should look like:

function[a] = test_sub(z,count)

   fprintf('\nPARAMETER %d ', count)
   fprintf('\n Value is %d \n', z);

   if (z==1) %if input equal to 0
      j=1; %store temporary value to j
      a=j; 
      disp('new value is 1')

   elseif (z==99)
      j=1;
      a=j;
      disp('new value is 100')
   else
      disp('unidentified error')
   end

   end
end

And the one that is responsible of repeating the thing is the one that should! if you want new parameters, change the amount of times it loops, not the amount of times it tests!

test_main(4) % will repeat the test 4 times

also change the call to test_sub() to test_sub(status,ii); adn the name i to ii (as i is the imaginary unit in matlab)