Determine element-wise equality, treating NaNs as equal
out = eqn (A, B)
eqn is just like
eq (the function that implements the
== operator), except
that it considers NaN and NaN-like values to be equal. This is the element-wise
isnanny to test for NaN and NaN-like values,
which means that NaNs and NaTs are considered to be NaN-like, and
string arrays’ “missing” and categorical objects’ “undefined” values
are considered equal, because they are NaN-ish.
Developer’s note: the name “
eqn” is a little unfortunate,
because “eqn” could also be an abbreviation for “equation”. But this
name follows the
isequaln pattern of appending an “n” to the
corresponding non-NaN-equivocating function.