@saehrimnir/druidjs / PCA

Class: PCA<T>

Defined in: dimred/PCA.js:29

Principal Component Analysis (PCA)

A linear dimensionality reduction technique that identifies the axes (principal components) along which the variance of the data is maximized.

Template

T

See

MDS for another linear alternative

Example

import * as druid from "@saehrimnir/druidjs";

const X = [[1, 2], [3, 4], [5, 6]];
const pca = new druid.PCA(X, { d: 2 });
const Y = pca.transform();
// [[x1, y1], [x2, y2], [x3, y3]]

Extends

• DR

Type Parameters

Type Parameter	Description
T extends InputType

Constructors

Constructor

new PCA<T>(X: T, parameters?: Partial<ParametersPCA>): PCA<T>;

Defined in: dimred/PCA.js:34

Parameters

Parameter	Type	Description
X	T	The high-dimensional data.
parameters?	Partial<ParametersPCA>	Object containing parameterization of the DR method.

Returns

PCA<T>

Overrides

DR.constructor

Properties

Property	Type	Inherited from	Defined in
__input	T	DR.__input	dimred/DR.js:46
_D	number	DR._D	dimred/DR.js:28
_is_initialized	boolean	DR._is_initialized	dimred/DR.js:34
_N	number	DR._N	dimred/DR.js:30
_parameters	ParametersPCA	DR._parameters	dimred/DR.js:49
_randomizer	Randomizer	DR._randomizer	dimred/DR.js:32
_type	"array" | "matrix" | "typed"	DR._type	dimred/DR.js:54
V	Matrix | undefined	-	dimred/PCA.js:93
X	Matrix	DR.X	dimred/DR.js:56
Y	Matrix	DR.Y	dimred/DR.js:58

Accessors

projection

Get Signature

get projection(): T;

Defined in: dimred/DR.js:219

Returns

T

The projection in the type of input X.

Inherited from

DR.projection

Methods

[dispose]()

dispose: void;

Defined in: dimred/DR.js:320

Alias of release for the using declaration, so a hand-driven run frees its buffers when the block exits. Note that transform and a completed or break-ed generator() already release on their own — this only matters for a generator abandoned part way.

using tsne = new TSNE(X, { d: 2 });
const steps = tsne.generator(500);
steps.next(); // buffers released when the enclosing block exits

Returns

void

Inherited from

DR.[dispose]

---

check_init()

check_init(): DR<T, ParametersPCA>;

Defined in: dimred/DR.js:210

If the respective DR method has an init function, call it before transform.

Returns

DR<T, ParametersPCA>

Inherited from

DR.check_init

---

generator()

generator(): Generator<T, T, void>;

Defined in: dimred/PCA.js:47

Transforms the inputdata X to dimensionality d.

Returns

Generator<T, T, void>

A generator yielding the intermediate steps of the projection.

Overrides

DR.generator

---

init()

abstract init(...args: unknown[]): void;

Defined in: dimred/DR.js:201

Parameters

Parameter	Type	Description
...args	unknown[]	-

Returns

void

Inherited from

DR.init

---

parameter()

Call Signature

parameter(): ParametersPCA;

Defined in: dimred/DR.js:82

Get all Parameters.

Returns

ParametersPCA

Inherited from

DR.parameter

Call Signature

parameter<K>(name: K): ParametersPCA[K];

Defined in: dimred/DR.js:88

Get value of given parameter.

Type Parameters

Type Parameter	Description
K extends keyof ParametersPCA

Parameters

Parameter	Type	Description
name	K	Name of the parameter.

Returns

ParametersPCA[K]

Inherited from

DR.parameter

Call Signature

parameter<K>(name: K, value: ParametersPCA[K]): PCA<T>;

Defined in: dimred/DR.js:95

Set value of given parameter.

Type Parameters

Type Parameter	Description
K extends keyof ParametersPCA

Parameters

Parameter	Type	Description
name	K	Name of the parameter.
value	ParametersPCA[K]	Value of the parameter to set.

Returns

PCA<T>

Inherited from

DR.parameter

---

principal_components()

principal_components(): Matrix;

Defined in: dimred/PCA.js:80

Computes the d principal components of Matrix X.

Returns

Matrix

---

release()

release(): PCA<T>;

Defined in: dimred/DR.js:302

Hands back the WASM buffers this instance is holding.

Only needed after driving generator() by hand and stopping early — a plain transform(), or a for…of over generator() (including one you break), already releases when it ends. It frees only this method's buffers, never another running instance's, and the next run simply reallocates, so it is safe to call at any time, more than once, and while other instances are mid-run.

Returns

PCA<T>

Example

const tsne = new TSNE(X, { d: 2 });
const steps = tsne.generator(500);
steps.next();
tsne.release(); // stop early and give the buffers back

Inherited from

DR.release

---

transform()

transform(): T;

Defined in: dimred/PCA.js:57

Transforms the inputdata X to dimensionality d.

Returns

T

• The projected data.

Overrides

DR.transform

---

transform_async()

transform_async(...args: unknown[]): Promise<T>;

Defined in: dimred/DR.js:241

Computes the projection.

Parameters

Parameter	Type	Description
...args	unknown[]	Arguments the transform method of the respective DR method takes.

Returns

Promise<T>

The dimensionality reduced dataset.

Inherited from

DR.transform_async

---

generator()

static generator<T>(X: T, parameters?: Partial<ParametersPCA>): Generator<T, T, void>;

Defined in: dimred/PCA.js:116

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters?	Partial<ParametersPCA>	-

Returns

Generator<T, T, void>

Overrides

DR.generator

---

principal_components()

static principal_components<T>(X: T, parameters: Partial<ParametersPCA>): Matrix;

Defined in: dimred/PCA.js:105

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters	Partial<ParametersPCA>	-

Returns

Matrix

---

transform()

static transform<T>(X: T, parameters: Partial<ParametersPCA>): T;

Defined in: dimred/PCA.js:70

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters	Partial<ParametersPCA>	-

Returns

T

Overrides

DR.transform

---

transform_async()

static transform_async<T>(X: T, parameters?: Partial<ParametersPCA>): Promise<T>;

Defined in: dimred/PCA.js:128

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters?	Partial<ParametersPCA>	-

Returns

Promise<T>

Overrides

DR.transform_async