// 微分幾何　56ページ　ポアンカレ単位円板

x0 = -4;
x80;
dx = 0.1;

y0 = 0;
y20;
dy = 0.2;

u1;

_U(x,y) {
　　RETURN((1-x^2-y^2)/(x^2+(1+y)^2));
};
_V(x,y) {
　　RETURN((2x/(x^2+(1+y)^2)));
};

∀(y,x,u) {
　　P(y,x,u:0) = _U(x(x),y(y));
　　P(y,x,u:1) = _V(x(x),y(y));
　　Q(x,y,u:0) = _U(x(x),y(y));
　　Q(x,y,u:1) = _V(x(x),y(y));
};
TITLE(x,"%s=%.1f","VAL");
TITLE(y,"\n%s=%.1f","VAL");
MPRT(P(y,x,u));
TITLE(x,"\n%s=%.1f","VAL");
TITLE(y,"%s=%.1f","VAL");
SKIPTITLE();
MPRT(Q(x,y,u));