function I=gaussint(mu,sigma,x_1,x_2)
% GAUSSINT  Integral of Gaussian PDF
%	I=gaussint(mu,sigma,x_1,x_2) performs the integration of a Gaussian
%	PDF p(x) with mean mu and variance sigma^2 with lower integration
%	limit x_1 and higher integration limit x_2.

I=0.5*erf((x_2-mu)./(sqrt(2)*sigma)) - 0.5*erf((x_1-mu)./(sqrt(2)*sigma));

