Ensuring that system is realized to velocity before asking for velocity of point on the model.
Ensuring that system is realized to velocity before asking for velocity of point on the model.

git-svn-id: 9e047e1e624cce0a2485e750063112e834f85522@5642 fc29be9c-2cb0-420d-b520-73dbd18add6e

opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core,opensim-org/opensim-core