Find the position of each desired value, i.e., x,
in a vector of strings.
Builds on match() by allowing x to be a combination of
strings to be matched and known positions.
find_position(x, table)A vector of strings and/or integers to be matched.
A vector of strings. If the character strings includes
values that can be coerced to integers, they must be in a matching position
in the vector. For example, table = c("3","4","1") will confuse the
function because x = 1 will produce a return value of 3 rather than 1.
An integer vector indicating the positions of x in table.
Same as match(), if x[i] is found to be equal to table[j], then
the value returned in the i-th position of the integer vector is j.
The smallest value of j, i.e., the first match, is always returned.
find_position() differs from match() in three ways.
First, values of x that are not found are removed. Thus, the length of
the integer vector has the potential to be shorter than the length of x.
Second, x can contain a mix of integer positions that are already known
and strings to be found.
Third, table cannot include integers that do not match their position.
See the specifications for table for more details.
See match() for a more formal version of find_position()
that returns an integer vector the same length as x.