function entropy( out, x ) {
	var len = x.length,
		i;
	if ( out.length !== len ) {
		throw new Error( 'entropy()::invalid input arguments. Input and output matrices must be the same length.' );
	}
	for ( i = 0; i < len; i++ ) {
		out.data[ i ] = ENTROPY( x.data[ i ] );
	}
	return out;
}
function entropy( out, x ) {
	var len = x.length,
		i;
	if ( out.length !== len ) {
		throw new Error( 'entropy()::invalid input arguments. Input and output matrices must be the same length.' );
	}
	for ( i = 0; i < len; i++ ) {
		out.data[ i ] = ENTROPY( x.data[ i ] );
	}
	return out;
}
function entropy ( out , x ) { var len = x . length , i ; if ( out . length !== len ) { throw new Error ( 'entropy()::invalid input arguments. Input and output matrices must be the same length.' ) ; } for ( i = 0 ; i < len ; i ++ ) { out . data [ i ] = ENTROPY ( x . data [ i ] ) ; } return out ; }
ENTROPY // 
FUNCTION: entropy( out, x )
Computes the distribution entropy for each parameter stored in a matrix.

@param {Matrix} out - output matrix
@param {Matrix} x - input matrix
@returns {Matrix} output matrix
ENTROPY // FUNCTION : entropy ( out x ) Computes the distribution entropy for each parameter stored in a matrix .