Question about the power law

[Lancerchiang]

% apply powerlaw
function x = powerlaw (x, a)
if a == 1, return; end
x = sign (x) .* abs(x)  .^ a;

Regarding to the powerlaw function above, "x" is the extracted feature vector and "a" is the original feature map of a different size, how is it possible to do abs(x) .^ a (element-wise power)?

Thanks!