## Sphere through four Points

Four non-coplanar points determine exactly one sphere. Given the coordinates of four
points the program computes the equation of the sphere and a cube symmetric to the axes
is plotted.

### Example:

Sphere through the points:
A(1|0|0), B(0|2|0), C(0|0|3), D(1|0|1)
Normal form:
| -> |-2,5 | |2
K : | x - |-0,5 | | = 12,75
| | 0,5 | |
Center and radius:
M(-2,5|-0,5|0,5)
r = 3,5707142