SpaceTest.dist

SpaceTest.dist(self)

Verify LinearSpace.dist.

The distance metric is checked for the following properties:

• positive definiteness:

  d(x, y) >= 0

  d(x, y) = 0 iff x = y

• symmetry:

  d(x, y) = d(y, x)

• sub-transitivity:

  d(x, z) <= d(x, y) + d(y, z)

• compatibility with the norm (if available):

  d(x, y) = ||x - y||

References

Wikipedia article on metric