function mgf( t, mu ) {
	if ( isnan( t ) || isnan( mu ) ) {
		return NaN;
	}
	return exp( mu*t );
}
Evaluates the moment-generating function (MGF) for a degenerate distribution centered at `mu`.

@param {number} t - input value
@param {number} mu - value at which to center the distribution
@returns {number} evaluated MGF

@example
var y = mgf( 1.0, 1.0 );
// returns ~2.718

@example
var y = mgf( 2.0, 3.0 );
// returns ~403.429

@example
var y = mgf( NaN, 0.0 );
// returns NaN

@example
var y = mgf( 0.0, NaN );
// returns NaN