RGB to Gray function with Matlab code

hi all , we all know the Matlab belt in rgb2gray ,

i am tring to do it myself ,, here's my function

function out=gray(x)
[p,q,n]=size(x);
%out=uint8(ones(m,n,p));

          R=x(:,:,1);
          G=x(:,:,2);
          B=x(:,:,3);
          out=((R+G+B)/3);

and i have this error whn calling gray()

??? Subscript indices must either be real positive integers or logicals.

i don't know what's wrong , if any one know the solution .. Thanx in advance ..

Answer 1

[Fangjun Jiang]

gray() is a MATLAB function too. Do the following to see if there are conflicts.

which gray -all

[jenny mat]

i changed the function name and it goes well but i have this error instead when viewing the resulted image..

g= rgbtogray2(x);

imshow(g)

//Error

??? Index exceeds matrix dimensions.

Error in ==> gray at 6

G=x(:,:,2);

Error in ==> imageDisplayParseInputs at 207

common_args.Map = gray(256);

Error in ==> imshow at 173

[common_args,specific_args] = ...

thanx in advance

[Fangjun Jiang]

You mean you change the name of your own gray() function? Why did the error message still say "Error in ==> gray at 6, G=x(:,:,2);"?

[jenny mat]

yes ,, i deleted the old one and it worked very well ..

thanx very much

Answer 2

[Walter Roberson]

Chances are you are trying to call gray() from within a routine in which you have a variable named "gray".