Class CompositionUtils

Utility functions for compositional data analysis

Index

Constructors

Methods

centre close geometricMean isValidTernary perturbe powerScale validateTernaryPoints

Constructors

constructor

new CompositionUtils(): CompositionUtils
Returns CompositionUtils

Methods

`Static`centre

centre(P: TernaryPoint[]): TernaryPoint
Calculate the center of a compositional dataset
Parameters
- P: TernaryPoint[]
  Array of ternary points
Returns TernaryPoint
The center point
- Defined in core/compositionUtils.ts:28

`Static`close

close(P: TernaryPoint[]): (null | TernaryPoint)[]
Close compositions to ensure they sum to 1
Parameters
- P: TernaryPoint[]
  Array of ternary points
Returns (null | TernaryPoint)[]
Closed compositions
- Defined in core/compositionUtils.ts:80

`Static`geometricMean

geometricMean(x: number[], removeZeros?: boolean): number
Calculate geometric mean of an array of numbers
Parameters
- x: number[]
  Array of numeric values
- removeZeros: boolean = true
  Whether to remove zeros before calculation
Returns number
The geometric mean
- Defined in core/compositionUtils.ts:14

`Static`isValidTernary

isValidTernary(point: TernaryPoint): boolean
Validate that a point is a valid ternary point (i.e., has three non-null components)
Parameters
- point: TernaryPoint
Returns boolean
- Defined in core/compositionUtils.ts:120

`Static`perturbe

perturbe(P: (null | TernaryPoint)[], c?: TernaryPoint): (null | TernaryPoint)[]
Perturbe a compositional dataset by a compositional vector
Parameters
- P: (null | TernaryPoint)[]
  Array of ternary points
- c: TernaryPoint = ...
  Perturbation vector
Returns (null | TernaryPoint)[]
Perturbated compositions
- Defined in core/compositionUtils.ts:46

`Static`powerScale

powerScale(P: (null | TernaryPoint)[], scale?: number): (null | TernaryPoint)[]
Power scaling of compositions
Parameters
- P: (null | TernaryPoint)[]
  Array of ternary points
- scale: number = 1
  Power scalar
Returns (null | TernaryPoint)[]
Scaled compositions
- Defined in core/compositionUtils.ts:65

`Static`validateTernaryPoints

validateTernaryPoints(P: (null | TernaryPoint)[]): void
Validate ternary points
Parameters
- P: (null | TernaryPoint)[]
  Array of ternary points to validate
Returns void
Throws
Error if any point has negative values or values don't sum to approximately 1
- Defined in core/compositionUtils.ts:96