math function for a vector

I'm working with Matlab R2012a. I have a simple question and I know there must be a simple answer, but searching and playing around with the syntax hasn't worked.

function sig = sigmoid( x)
  sig = 1/(1+exp(-x));
end

This function works in Octave as is, but in Matlab it only works with scalars. What is the syntax for this function when x is a vector or matrix and I need this applied element wise? I tried the "." notation to no avail. I know I can loop through all the elements of x, but is there a more elegant way?

Answer 1

[Azzi Abdelmalek]

function sig = sigmoid( x)
sig = 1./(1+exp(-x));

[Eugene]

Perfect, thank you! Not sure how I missed this.