The CQL command Boundary describes constraints within an ordered sequence (see cql_sequence()). Groups of events between two boundaries are assumed to be sampled from the same prior distribution. Boundary alone models a uniform prior. Other types of boundary, i.e. Sigma_Boundary, Tau_Boundary, and Zero_Boundary are not yet implemented in stratigraphr.

Boundaries can contain a Transition command, in which case they describe a non-instantaneous transition or 'trapezium' prior.

cql_boundary(name, ..., prior = NULL)

cql_sigma_boundary()

cql_tau_boundary()

cql_zero_boundary()

cql_transition(name, prior = NULL)

## Arguments

name Character. Label for a boundary or transition. cql objects contained within a boundary. cql object. Expression describing the prior likelihood of a boundary or transition.

A cql object.

## References

https://c14.arch.ox.ac.uk/oxcalhelp/hlp_analysis_oper.html#group

https://c14.arch.ox.ac.uk/oxcalhelp/hlp_commands.html