what is wrong in this code in matlab?

hi can you tell me what is wrong in this code becouse o got wrong message which is (??? Undefined function or method 'sqr' for input arguments of type 'double')

          for (c1=sqr(features1(:,j)- mean_of_column1); and 
  p1=0;
  p2=0;
  for j=1:c
      c1=sqr(features1(:,j)- mean_of_column1);
      c2=sqr(features2(:,j)- mean_of_column2);
          p1=p1+c1;
          p2=p2+c2;
  end;
        denominator=sqrt(p1)* sqrt(p2);

[Walter Roberson]

'and' is not valid at that position in the code.

Answer 1

[Matt Fig]

You probably mean to use the SQRT function to find the square root.

In response to your clarifying comment,

sqr = @(x) x.^2; % Define this first, before you use it!
sqr(5)

[Matt Fig]

Another example of the poor search capabilities on TMW website. Searching for sqrt in "latest documentation" doesn't turn up the non-symbolic form of this function in the first three pages!

[Taleb Almajrbi]

no, i want to use example if x=5

sqr(x)must = 25 how can i use it in matlab

[Matt Fig]

In that case:

sqr = @(x) x.^2; % Define this first.

sqr(5)

[Taleb Almajrbi]

hi Matt

so how can i use this in my code

many thanks

[Matt Fig]

Just like I showed you! First define the function, then use the function. Put the function definition line

sqr = @(x) x.^2; % Define this first.

anywhere in the code BEFORE you use it.

[Taleb Almajrbi]

hi matt

i got another wrong message which is (??? Error using ==> mtimes

Inner matrix dimensions must agree.) for denominator=sqrt(p1)* sqrt(p2); in the same code.

can you solve it to me?

thanks

[Matt Fig]

Yes, whenever you are working with arrays and need to do element by element multiplication, use this instead:

sqrt(p1).* sqrt(p2); % Notice the .* instead of * only.

The same goes for / and ^.