Multiplying elements of a vector

I'm creating a function to find areas of shapes. It takes two inputs, the first is a vector and the second is a variable number.

function area = area_calculator(A, num)

switch num
    case 1   % Circle
        r = norm(A);
        A = pi*r^2   % Area
    case 2     % Rectangle
        A = b*h % Area; I want to multiply vector element 1 by vector element 2
end

So if I give it

>> area_calculator([2,4], 2)

I'm wanting b*h to be 2*4

I'm unsure how to instruct matlab to perform multiplication within the vector

Thank you very much

Answer 1

[madhan ravi]

Use prod() to perform multiplication within a vector.

function area = area_calculator(vector, num)

switch num
    case 1   % Circle
        r = norm(vector);
        area = pi*r^2   % Area
    case 2     % Rectangle
        area = prod(vector);% or you can use vector(1)*vector(2) % Area; I want to multiply vector element 1 by vector element 2
end

Answer 2

[per isakson]

Replace

case num == 1 

by

case 1 

[Stephen Warren]

Thanks, that makes it cleaner.

How do I perform multiplication of elements from within one vector