Convert an S4 SpatialStreamNetwork object
created in the SSN package to an S3 SSN object used in the
SSN2 package.
SSN_to_SSN2(object)A SpatialStreamNetwork object
An S3 SSN class object.
SSN_to_SSN2() has been made available to help users
migrate from the SSN package to the updated SSN2
package. It is used to convert existing S4 SpatialStreamNetwork
objects stored in saved workspaces to the S3 SSN class object
used in the SSN2 package. Note that ssn_import is
used to create an S3 SSN object from data stored locally in a .ssn
directory.