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RandomProjections

Generate features from random linear projections of the input data.

This node will essentially generate a random matrix, and transform the data by that matrix. Typically, this is used either to reduce the dimensionality of the data, or to generate novel combinations of features when used with subsequent non-linear transformations. By default this node will auto-determine the number of components (and thus the number of output features) from the data. Like most other feature extraction nodes, this node can compute features between elements of an axis of your choice while treating elements of another axis as the observations, trials, or samples. It can also optionally compute multiple separate models on different slices of the data along some axis of choice. It is also possible to pool multiple axes for any of these roles. More Info... Version 1.0.0

Ports/Properties

domain_axes

Axes which form the input domain of the transformation. Features are computed between elements along these axes (or in other words, elements along these axes will be combined with each other to yield features). This is a comma-separated list of axis names (for example: "space, frequency"), possibly empty, or the special string "(all others)", which stands for all axes that are not listed in the other two lists of axes. For time-series data, this is usually the space axis, and if features have already been extracted from the data through some other method, it would be the features axis. In rare cases it can also include other axes, such as frequency, lag, and time. This axis drops out of the data and is replaced by a feature axis that has a number of elements that corresponds to the output feature dimension of the model.

verbose name
Compute Features Between Axes
default value
(all others)
port type
ComboPort
value type
str (can be None)

aggregate_axes

Axes that have the statistical observations in them. The elements along these axes are treated as the "trials", "samples", or, equivalently, "observations". Adaptive feature extractors will aggregate statistics along the elements of these axes during training. When the transformer applies to data, this axis remains in the data (if multiple, they will be flattened into one axis, however). This is a comma-separated list of axis names (for example: "time, instance"), possibly empty, or the special string "(all others)", which stands for all axes that are not listed in the other two lists of axes. This is almost always the instance axis (especially if the data has already been segmented, i.e., if the Segmentation node was used), but in some cases it may also be the time axis, or occasionally other axes.

verbose name
Treat Elements As Trials/samples Along Axes
default value
instance
port type
ComboPort
value type
str (can be None)

separate_axes

Axes along which to learn separate models. It is possible to use multiple separate feature-extraction models, each of which operates on a different slice of the data. This node does not combine data between elements along these axes in any way (although features between these elements may of course be combined in later stages, for instance in a classifier node). This is a comma-separated list of axis names (for example: "time, frequency"), possibly empty, or the special string "(all others)", which stands for all axes that are not listed in the other two lists of axes. This axis, if any, will also persist in the data.

verbose name
Compute Separate Models Along Axes
default value
port type
ComboPort
value type
str (can be None)

data

Data to process.

verbose name
Data
default value
None
port type
DataPort
value type
Packet (can be None)
data direction
INOUT

num_components

Number of components to generate. If left to the default, the number of components will be determined based on the input data. This can be fairly conservative, i.e., the number of output components may be larger than strictly necessary to represent the input well enough.

verbose name
Number Of Components
default value
None
port type
IntPort
value type
int (can be None)

epsilon

Embedding quality. Only used when the number of components is auto-deduced. Smaller values yield higher-quality embeddings and higher-dimensional results.

verbose name
Epsilon
default value
0.1
port type
FloatPort
value type
float (can be None)

random_seed

Random seed. Different values yield different projections.

verbose name
Random Seed
default value
12345
port type
IntPort
value type
int (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

verbose name
Set Breakpoint (Debug Only)
default value
False
port type
BoolPort
value type
bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

verbose name
Metadata
default value
{}
port type
DictPort
value type
dict (can be None)