Undefined function or variable 'a'.

My current problem refers to the below script and function.

clear;
  for x=100:145
  assfunct1(x);
  fprintf('x: %d, a: %d, b: %d, c: %d\n', x, a, b, c);
  end;

&

function [a,b,c] = assfunct1(x)
if x<0 || fix(x) ~=x;
   disp('error, input is not a non negative integer')
return
end
for a=1:x
    b=sqrt(5*a^3);
    c=sqrt((a+b)^2);
end
    [a,b,c]
end

>> Assignment1

ans =

     1.0e+03 *

      0.1000    2.2361    2.3361

Undefined function or variable 'a'.

Error in Assignment1 (line 4)
fprintf('x: %d, a: %d, b: %d, c: %d\n', x, a, b, c);

Been trying for hours to work where I have erred, ty for any help you can offer.

[Image Analyst]

You forgot to give the code for assfunct3(). You only gave it for assfunct1().

And can we assume that the code starting with "clear" is in a separate m-file, and not below assfunct1() definition in the same file?

[Scott]

yes that's a typo, the code is for assfunct1 in the script

[CS Researcher]

I answered this a few days back and as John correctly pointed out you should do this:

clear;
for x=100:145
  [a,b,c] = assfunct1(x);
  fprintf('x: %d, a: %d, b: %d, c: %d\n', x, a, b, c);
end;

Answer 1

[John BG]

You have to collect the output of your custom function assfunct3() with a variable that then you have to feed in the fprintf.

Since you call assfunct3 but do not collect the result with anything, then fprintf does not really know what variable 'a' is because the 'a' you use in the header of the assfunct3 remains local to that function.

If you find this answer of any help solving your question,

please click on the thumbs-up vote link,

thanks in advance

John

[e-mail]

Answer 2

[Jan]

You have to catch the outputs of the function:

for x = 100:145
  [a, b, c] = assfunct3(x);
  fprintf('x: %d, a: %d, b: %d, c: %d\n', x, a, b, c);
end

Note that the values of b and c are overwritten in each iteration:

for a = 1:x
  b = sqrt(5*a^3);
  c = sqrt((a+b)^2);
end
[a,b,c]

What is your intention?