passing a function to another function

Hi

I am trying to pass the following function "haar" to the function integral. I am getting the following error. plz suggest. thanks

function val = haar(x)

if ((0<=x) && (x<0.5))
    val=1;
elseif ((0.5<= x) && (x < 1))
    val =-1;
else
    val =0;
end
end
EDU>> fhnadle=@haar;
EDU>> integral(fhnadle,0,1)
Operands to the || and && operators must be convertible to logical scalar values

Answer 1

[Sean de Wolski]

integral calls the function with a vector x, you're expecting x to be a scalar in your haar function. E.g:

>> [1 2 3] && 1

The easiest thing for you to do is to modify haar to use logical indexing on val:

function val = haar(x)

val = zeros(size(x)); % assume zero
val(0<=x & x<0.5) = 1; % set ones
val(0.5<=x & x<1) = -1; % set -1s

end

[R yan]

thank you. it works fine.

Can I write the same using symbolic?? I tried using symfun but dont know how to write the IF-else part.

thanks