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Convex hull Lambda > would it be impossible to build?
Hello everyone, Ever since visiting the site of Andy Pope, I saw a chart that fascinated me because it can be very useful for creating the bounding area of a set of points. It's known as Convex ...
I got some progress to connect the outer point.
=LET(xy,B3:C99,z,FILTER(xy,TAKE(xy,,1)<>""),r,SEQUENCE(ROWS(z)),st,XMATCH(0,DROP(z,,1),1),
RAD,LAMBDA(p,q,ATAN2(INDEX(q,1)-INDEX(p,1),INDEX(q,2)-INDEX(p,2))),
pl,REDUCE(HSTACK(st,0),r,LAMBDA(a,i,IF((ROWS(a)>1)*(INDEX(a,ROWS(a),1)=st),a,
LET(b,CHOOSEROWS(z,TAKE(a,-1,1)),
Nx,FILTER(r,ISNA(XMATCH(r,DROP(VSTACK(TAKE(a,,1),0),1)))),
Nr,XLOOKUP(0,MAP(Nx,LAMBDA(n,MOD(RAD(b,CHOOSEROWS(z,n))-TAKE(a,-1,-1),2*PI()))),Nx,,1),
VSTACK(a,HSTACK(Nr,RAD(b,CHOOSEROWS(z,Nr)))))))),
CHOOSEROWS(z,TAKE(pl,,1)))
https://1drv.ms/x/s!Ak8Fla2fCeo6gvFJ7YKoPlwaDwj23A?e=rU0dyn
