Github user srowen commented on a diff in the pull request:

    https://github.com/apache/spark/pull/16344#discussion_r93613064
  
    --- Diff: 
mllib/src/main/scala/org/apache/spark/ml/regression/GeneralizedLinearRegression.scala
 ---
    @@ -397,49 +436,132 @@ object GeneralizedLinearRegression extends 
DefaultParamsReadable[GeneralizedLine
     
         /** Trim the fitted value so that it will be in valid range. */
         def project(mu: Double): Double = mu
    +
       }
     
       private[regression] object Family {
     
         /**
    -     * Gets the [[Family]] object from its name.
    +     * Gets the [[Family]] object based on family and variancePower.
    +     * 1) retrieve object based on family name
    +     * 2) if family name is tweedie, retrieve object based on variancePower
          *
    -     * @param name family name: "gaussian", "binomial", "poisson" or 
"gamma".
    +     * @param model a GenerealizedLinearRegressionBase object
          */
    -    def fromName(name: String): Family = {
    -      name match {
    -        case Gaussian.name => Gaussian
    -        case Binomial.name => Binomial
    -        case Poisson.name => Poisson
    -        case Gamma.name => Gamma
    +    def fromModel(model: GeneralizedLinearRegressionBase): Family = {
    +      model.getFamily match {
    +        case "gaussian" => Gaussian
    +        case "binomial" => Binomial
    +        case "poisson" => Poisson
    +        case "gamma" => Gamma
    +        case "tweedie" =>
    +          model.getVariancePower match {
    +            case 0.0 => Gaussian
    +            case 1.0 => Poisson
    +            case 2.0 => Gamma
    +            case default => new TweedieFamily(default)
    +          }
           }
         }
       }
     
       /**
    -   * Gaussian exponential family distribution.
    -   * The default link for the Gaussian family is the identity link.
    -   */
    -  private[regression] object Gaussian extends Family("gaussian") {
    +    * Tweedie exponential family distribution.
    +    * This includes the special cases of Gaussian, Poisson and Gamma.
    +    */
    +  private[regression] class TweedieFamily(private val variancePower: 
Double)
    +    extends Family{
    +
    +    val name: String = variancePower match {
    --- End diff --
    
    Why remove the name and switch like this? you can instead adjust this so 
that subclasses override a `name` method.


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org

Reply via email to