function Degenerate() {
	var mu;
	if ( !(this instanceof Degenerate) ) {
		if ( arguments.length === 0 ) {
			return new Degenerate();
		}
		return new Degenerate( arguments[ 0 ] );
	}
	if ( arguments.length ) {
		mu = arguments[ 0 ];
		if ( !isNumber( mu ) || isnan( mu ) ) {
			throw new TypeError( format( 'invalid argument. Mean parameter `%s` must be a number. Value: `%s`.', 'mu', mu ) );
		}
	} else {
		mu = 0.0;
	}
	defineProperty( this, 'mu', {
		'configurable': false,
		'enumerable': true,
		'get': function get() {
			return mu;
		},
		'set': function set( value ) {
			if ( !isNumber( value ) || isnan( value ) ) {
				throw new TypeError( format( 'invalid assignment. Must be a number. Value: `%s`.', value ) );
			}
			mu = value;
		}
	});
	return this;
}
Degenerate distribution constructor.

@constructor
@param {number} [mu=0.0] - constant value of distribution
@throws {TypeError} `mu` must be a number
@returns {Degenerate} distribution instance

@example
var degenerate = new Degenerate();

var y = degenerate.cdf( 1.8 );
// returns 1.0

var v = degenerate.median;
// returns 0.0