@saehrimnir/druidjs / SAMMON

Class: SAMMON<T>

Defined in: dimred/SAMMON.js:30

Sammon's Mapping

A nonlinear dimensionality reduction technique that minimizes a stress function based on the ratio of pairwise distances in high and low dimensional spaces.

A given seed reproduces a layout exactly within one engine and library build, but not across browsers or Node versions: the gradient step is chaotic, so a last-bit difference grows into a visibly different — though equally valid — layout. See DR for why, and SMACOF for a stable alternative.

Template

T

Extends

• DR

Type Parameters

Type Parameter	Description
T extends InputType

Constructors

Constructor

new SAMMON<T>(X: T, parameters?: Partial<ParametersSAMMON<AvailableInit>>): SAMMON<T>;

Defined in: dimred/SAMMON.js:47

SAMMON's Mapping

Parameters

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

Returns

SAMMON<T>

See

https://arxiv.org/pdf/2009.01512.pdf

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	ParametersSAMMON<AvailableInit>	DR._parameters	dimred/DR.js:49
_randomizer	Randomizer	DR._randomizer	dimred/DR.js:32
_type	"array" | "matrix" | "typed"	DR._type	dimred/DR.js:54
distance_matrix	Matrix | undefined	-	dimred/SAMMON.js:37
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

_step()

_step(): Matrix;

Defined in: dimred/SAMMON.js:130

Returns

Matrix

---

[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, ParametersSAMMON<AvailableInit>>;

Defined in: dimred/DR.js:210

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

Returns

DR<T, ParametersSAMMON<AvailableInit>>

Inherited from

DR.check_init

---

generator()

generator(max_iter?: number): Generator<T, T, void>;

Defined in: dimred/SAMMON.js:114

Transforms the inputdata X to dimenionality 2.

Parameters

Parameter	Type	Default value	Description
max_iter?	number	200	Maximum number of iteration steps. Default is 200

Returns

Generator<T, T, void>

A generator yielding the intermediate steps of the projection of X.

Overrides

DR.generator

---

init()

init(D: Matrix | undefined): asserts D is Matrix;

Defined in: dimred/SAMMON.js:68

Initializes the projection.

Parameters

Parameter	Type	Description
D	Matrix | undefined	-

Returns

asserts D is Matrix

Overrides

DR.init

---

parameter()

Call Signature

parameter(): ParametersSAMMON;

Defined in: dimred/DR.js:82

Get all Parameters.

Returns

ParametersSAMMON

Inherited from

DR.parameter

Call Signature

parameter<K>(name: K): ParametersSAMMON<AvailableInit>[K];

Defined in: dimred/DR.js:88

Get value of given parameter.

Type Parameters

Type Parameter	Description
K extends keyof ParametersSAMMON<AvailableInit>

Parameters

Parameter	Type	Description
name	K	Name of the parameter.

Returns

ParametersSAMMON<AvailableInit>[K]

Inherited from

DR.parameter

Call Signature

parameter<K>(name: K, value: ParametersSAMMON<AvailableInit>[K]): SAMMON<T>;

Defined in: dimred/DR.js:95

Set value of given parameter.

Type Parameters

Type Parameter	Description
K extends keyof ParametersSAMMON<AvailableInit>

Parameters

Parameter	Type	Description
name	K	Name of the parameter.
value	ParametersSAMMON<AvailableInit>[K]	Value of the parameter to set.

Returns

SAMMON<T>

Inherited from

DR.parameter

---

release()

release(): SAMMON<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

SAMMON<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(max_iter?: number): T;

Defined in: dimred/SAMMON.js:94

Transforms the inputdata X to dimensionality 2.

Parameters

Parameter	Type	Default value	Description
max_iter?	number	200	Maximum number of iteration steps. Default is 200

Returns

T

The projection of X.

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<ParametersSAMMON<AvailableInit>>): Generator<T, T, void>;

Defined in: dimred/SAMMON.js:205

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters?	Partial<ParametersSAMMON<AvailableInit>>	-

Returns

Generator<T, T, void>

Overrides

DR.generator

---

transform()

static transform<T>(X: T, parameters?: Partial<ParametersSAMMON<AvailableInit>>): T;

Defined in: dimred/SAMMON.js:194

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters?	Partial<ParametersSAMMON<AvailableInit>>	-

Returns

T

Overrides

DR.transform

---

transform_async()

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

Defined in: dimred/SAMMON.js:217

Type Parameters

Type Parameter	Description
T extends InputType

Parameters

Parameter	Type	Description
X	T	-
parameters?	Partial<ParametersSAMMON<AvailableInit>>	-

Returns

Promise<T>

Overrides

DR.transform_async