function out=gauss(ampl,sigma,wave,wave0)

% Syntax: out=gauss(ampl,sigma,wave,wave0)
% where wave is a vector,
% ampl is a scalar denoting the 'amplitude' of the Gaussian,
% sigma is a scalar denoting the FWHM of the Gaussian, and
% wave0 is the centre position of the Gaussian.
% out is a output vector of the same dimension as wave.
% 
% This function returns a Gaussian vector with the parameters
% given by the input.

 out=ampl/sigma * exp(-((wave-wave0)/sigma).^2/2);