collocation
points
20
v
0
.
5
D
0
.
2
t
0
.
5
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
0
2
4
6
8
10
0
.
0
0
.
2
0
.
4
0
.
6
0
.
8
1
.
0
x
c
