The following node is available in the Open Source KNIME predictive analytics and data mining platform version 2.7.1. Discover over 1000 other nodes, as well as enterprise functionality at
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MDS Projection (DistMatrix)
This node maps data of a high dimensional space onto a lower (usually
2 or 3) dimensional space with respect to a set of fixed data points.
Therefore modified Sammons mapping is applied, which iteratively
decreases the difference of the distances of high and low dimensional
data. When adjusting the position of a low dimensional data point by
default not its neighbors (or all other data points) are taken into
account but a specified set of fixed data points which are not modified.
Additionally all the other data points (and not only the fixed points)
can be taken into account when adjusting its positions, therefore the
setting "Project only" has to be unchecked. If the setting is checked
the data points will be mapped only with respect to the fixed data.
The distances of the data points to project in high dimensional space
as well as the distances of the fixed data (to the data to project)
must be provided by distance matrix columns.
Dialog Options
- Number of rows to use
-
Specifies the number of rows to apply the MDS on.
- Project only
-
If checked the input data is mapped only with respect to the specified
fixed data points (see tab 'Fixed data'). If unchecked, the other
(not fixed) data points are taken into account too, when adjusting
the position of each single data point.
- Epochs
-
Specifies the number of epochs to train.
- Learn rate
-
Specifies the learning rate to use. The learning rate
is decreased automatically over the trained epochs.
- Random seed
-
Specifies the random seed to use, which allows to reproduce a mapping
even if the initialization is done randomly.
- Output dimension
-
Specifies the dimension of the mapped output data.
- Distance matrix column of data to project
-
The column (of data table at port 1) containing the distances of the
data points to project (to itself and the data points to project).
- MDS columns
-
Specifies the columns to use as fixed (mds column) data. Be aware that
the chosen columns represent the lower dimensional data which is used
to project the input data to.
The number of columns to choose has to be equal to the output dimension.
- Distance matrix column of fixed data
-
The column (of data table at port 0) containing the distances of the
fixed data points (to itself and the data points to project).
Ports
Input Ports
0 |
Data table containing the fixed data points.
|
1 |
Data table containing the data to map.
|
Output Ports
0 |
The input data and the mapped data.
|
This node is contained in KNIME Distance Matrix Extension
provided by KNIME GmbH, Konstanz, Germany.