logical value, value at indices not specified by positions.
Defaults to FALSE. Cannot be NA.
Details
values and positions are expected to be the same length, and are allowed
to both have zero length.
Allowed values for value are logical values. Missing values such as NA
and NA_real_ are allowed. Everything else is disallowed, The values are
also not allowed to take the same value as default.
positions should be integers or integer-like doubles. Everything else is
not allowed. Positions should furthermore be positive (0 not allowed),
unique, and in increasing order. Lastly they should all be smaller that
length.
For developers:
setting options("sparsevctrs.verbose_materialize" = TRUE) will print a
message each time a sparse vector has been forced to materialize.