> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fincept.in/llms.txt
> Use this file to discover all available pages before exploring further.

# Power Transformations (Box-Cox, Yeo-Johnson)

> Applies power transformations to make data more Gaussian-like. Box-Cox for positive data, Yeo-Johnson for any data. Improves linear model assumptions and reduces skewness. [Tier: ENTERPRISE, Credits: 10]



## OpenAPI

````yaml api-specs/ml.json post /quantlib/ml/preprocessing/transform
openapi: 3.1.0
info:
  title: FinceptQuantLib API - ML
  description: >-
    Machine Learning and Credit Risk module endpoints for FinceptQuantLib API.
    Pro Tier access required (5 credits per request). Covers credit scoring,
    model validation, regression models, clustering, anomaly detection, feature
    engineering, and preprocessing.
  version: 3.0.0
  contact:
    name: Fincept API Support
    url: https://fincept.in
servers:
  - url: https://api.fincept.in
    description: Fincept API Production Server
security:
  - APIKeyHeader: []
tags:
  - name: quantlib-ml
    description: Machine Learning and Credit Risk Analytics
    x-displayName: ML
paths:
  /quantlib/ml/preprocessing/transform:
    post:
      tags:
        - quantlib-ml
      summary: Power Transformations (Box-Cox, Yeo-Johnson)
      description: >-
        Applies power transformations to make data more Gaussian-like. Box-Cox
        for positive data, Yeo-Johnson for any data. Improves linear model
        assumptions and reduces skewness. [Tier: ENTERPRISE, Credits: 10]
      operationId: power_transform
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - X
              properties:
                X:
                  type: array
                  description: Feature matrix
                  items:
                    type: array
                    items:
                      type: number
                  example:
                    - - 100
                      - 0.5
                    - - 200
                      - 1.3
                    - - 150
                      - 0.9
                method:
                  type: string
                  description: Transformation method
                  enum:
                    - power
                    - box_cox
                  default: power
                  example: box_cox
      responses:
        '200':
          description: Transformed data
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                    example: true
                  data:
                    type: object
                    properties:
                      transformed:
                        type: array
                        items:
                          type: array
                          items:
                            type: number
                        description: Power-transformed data
                        example:
                          - - 4.605
                            - -0.693
                          - - 5.298
                            - 0.262
                          - - 5.011
                            - -0.105
                      method:
                        type: string
                        example: box_cox
        '401':
          $ref: '#/components/responses/UnauthorizedError'
        '402':
          $ref: '#/components/responses/InsufficientCreditsError'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  responses:
    UnauthorizedError:
      description: Authentication information is missing or invalid
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: string
                example: Invalid API key
    InsufficientCreditsError:
      description: Insufficient credits for this operation
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: string
                example: Insufficient credits. This endpoint requires 5 credits.
    ValidationError:
      description: Request validation error
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: array
                items:
                  type: object
                  properties:
                    loc:
                      type: array
                      items:
                        type: string
                    msg:
                      type: string
                    type:
                      type: string
  securitySchemes:
    APIKeyHeader:
      type: apiKey
      in: header
      name: X-API-Key
      description: >-
        API key for authentication. Get your key at
        https://api.fincept.in/auth/register

````