procedure vball(var r,s: scalar; var v: vector);
var
  i: integer;
  sf: scalar;
begin { vball }
  squot(sone,s,sf);
  sf.l.si:=0;
  sabs0(r,v[0]);
  for i:=1 to vdim do begin
    sprod(sf,v[i-1],v[i]);
    isdiv(i,v[i]);
  end;
  for i:=0 to vdim do with v[i] do begin
    l:=u;
    l.si:=-1;
  end;
  v[vdim].l.si:=0;
end { vball };