Database Reference
In-Depth Information
Fig. 12.9 Scheme of
dynamic transformations
(MiningFilterStream)
Mining
Transformer
MiningFilter
Stream
target
MiningInput
Stream
source
MiningInput
Stream
source
MiningOutput
Stream
target
MiningStream
Transformer
MiningOutput
Stream
target
Fig. 12.10 Scheme of static transformations (MiningStreamTransformer)
We have seen that
MiningTransformer
transforms one mining vector into
another. Hence, this transformation type transforms attribute values and represents
a vector transformation in the attribute space.
Transformations of Mining Input Streams
The transformations of mining input streams are the more general ones and
implement the
MiningStreamTransformer
interface. The
MiningStream-
Transformer
interface consists of one method
transform
which takes a
source
mining input stream as input and a
target
mining output stream as output of the
transformation. Obviously, this type of transformation covers almost any type of
transformations of mining input streams. We call this type of transformations
stream transformations
(Fig.
12.10
).
Regarding mining input streams, both types of transformations result in the
following transformation types:
•
Static transformations
: Here a stream transformation object (that hence imple-
ments the
MiningStreamTransformer
interface) converts the source stream into
the target stream only
once
, and then the transformed data is available in the
target mining input stream.
•
Dynamic transformations
: Here a vector transformation object (that hence
implements the
MiningTransformer
interface) is used in
MiningFilterStream
