ElementwiseProduct multiplies each input vector by a provided “weight” vector, using element-wise multiplication. In other words, it scales each column of the dataset by a scalar multiplier. This represents the Hadamard product between the input vector, v and transforming vector, w, to yield a result vector.
import org.apache.spark.ml.feature.ElementwiseProduct
import org.apache.spark.ml.linalg.Vectors
// Create some vector data; also works for sparse vectors
val dataFrame = spark.createDataFrame(Seq(
("a", Vectors.dense(1.0, 2.0, 3.0)),
("b", Vectors.dense(4.0, 5.0, 6.0)))).toDF("id", "vector")
val transformingVector = Vectors.dense(0.0, 1.0, 2.0)
val transformer = new ElementwiseProduct()
// Batch transform the vectors to create new column:
| id| vector|transformedVector|
| a|[1.0,2.0,3.0]| [0.0,2.0,6.0]|
| b|[4.0,5.0,6.0]| [0.0,5.0,12.0]|