input field index.
used as feature name prefix.
pre-hashed namespace.
bit mask applied to final hash.
lambda to unify the cast/conversion to double.
Pre-hashed feature index.
Featurize a single row.
Featurize a single row.
input row.
output indices.
output values.
this interface isn't very Scala-esce, but it avoids lots of allocation. Also due to SparseVector limitations we don't support 64bit indices (e.g. indices are signed 32bit ints)
input field index.
input field index.
lambda to unify the cast/conversion to double.
Featurize numeric values into native VW structure. ((hash(column name):value)