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

    https://github.com/apache/spark/pull/13796#discussion_r74678564
  
    --- Diff: 
mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
 ---
    @@ -945,13 +955,139 @@ class BinaryLogisticRegressionSummary 
private[classification] (
     private class LogisticAggregator(
         private val numFeatures: Int,
         numClasses: Int,
    -    fitIntercept: Boolean) extends Serializable {
    +    fitIntercept: Boolean,
    +    multinomial: Boolean,
    +    standardize: Boolean) extends Serializable {
     
       private var weightSum = 0.0
       private var lossSum = 0.0
     
    -  private val gradientSumArray =
    -    Array.ofDim[Double](if (fitIntercept) numFeatures + 1 else numFeatures)
    +  private val totalCoefficientLength = {
    +    val cols = if (fitIntercept) numFeatures + 1 else numFeatures
    +    val rows = if (multinomial) numClasses else 1
    +    rows * cols
    +  }
    +
    +  private val gradientSumArray = 
Array.ofDim[Double](totalCoefficientLength)
    +
    +  /** Update gradient and loss using binary loss function. */
    +  private def binaryUpdateInPlace(
    +      features: Vector,
    +      weight: Double,
    +      label: Double,
    +      coefficients: Array[Double],
    +      gradient: Array[Double],
    +      featuresStd: Array[Double],
    +      numFeaturesPlusIntercept: Int,
    +      standardize: Boolean): Unit = {
    +    val margin = - {
    +      var sum = 0.0
    +      features.foreachActive { (index, value) =>
    +        if (featuresStd(index) != 0.0 && value != 0.0) {
    +          val x = if (standardize) value / featuresStd(index) else value
    --- End diff --
    
    Based on your documentation on `Feature scaling`, you said that you're 
caching the `scaled features` to improve the performance, then why do you need 
to divide by  `featuresStd(index)` if `standardize == true`?


---
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