TRIADIC
"space centre radiuses (radiuses as a complex, quaternion... number)" 
	DECAPSULATE DUP MULTIPLY "(a^2 b^2)"
	@.r2 ASSIGN SHAPE @.sh SET
	SWAP INTERVAL SWAP SUBTRACT "Define the centre"
	"Elipse: "
	MONADIC
		DECAPSULATE "(x y)" (0 0 0 0 0 0 0) CATENATE .sh RESHAPE
		DUP MULTIPLY "(x^2 y^2)"
		.r2 DIVIDE "(x^2/a^2 y^2/b^2)"
		SUM 1 NOTGREATER;
	EACH
	'*' MULTIPLY "Convert for output";
OPERATOR @elipsoid SET
'<space centre radiuses> elipsoid.' PRINT.