persistence has been
superseded by the scalednap
package — a strict superset that provides the same functions
(cluster_milano(), global_persistence(),
local_persistence()) and additional functionality — and is
being retired from CRAN. Please switch to scalednap
(install.packages("scalednap"); the same algorithm is also
available for Python via pip install scalednap). A startup
message now points users to the replacement. This is the final release
of persistence.