Determine whether a set of age labels refer to one-year, five-year, or life-table age groups.
Details
The valid types of age labels are:
"single"
. One-year age groups, eg"0"
or"55"
, and possibly an open age group, eg"90+"
."five"
. Five-year age groups, eg"0-4"
or"55-59"
, and possibly an open age group, eg"100+"
."lt"
. Life table age groups, eg"0"
,"1-4"
,"5-9"
,"55-59"
, or"80+"
.
If x
does not fit any of these
descriptions, then age_group_type()
throws
an error.
If x
could belong to
more than one type, then age_group_type()
prefers "single"
to "five"
and "lt"
,
and prefers "five"
to "lt"
.