All Questions
123
questions
1
vote
0
answers
46
views
Get compiler to notice exhaustive match on Vector
The following code defines an exhaustive match over a Vector, v.
def testExhaustiveness(v: Vector[Int]) = {
v match {
case Vector() => println("v is empty")
case ns :+ n => ...
- 959
0
votes
0
answers
19
views
VectorAssembler gives struct type output instead of vector type
I'm converting two columns of double type to a vector using VectorAssembler but I'm getting a struct with all the vector parameters as the output. This is the code for the vector transform
val ...
- 17
0
votes
1
answer
49
views
Scala - How to keep multiple values only once and remove other redundant values from a map
Given an input map as below:
val inputVal = Map(
0 -> Vector(("a", (0,1)),("b",(0,2)),("a",(2,3)),("c",(1,1))),
1 -> Vector(("a", (0,1)),(&...
- 51
1
vote
1
answer
50
views
Does Scala's Vector add any new methods on top of those provided by Seq and other superclasses?
Are there any methods in Scala's Vector that are not declared by its superclasses like AbstractSeq?
I am working on providing language localization (translation) for a learning environment/IDE built ...
0
votes
1
answer
68
views
Unable to "explode" spark vector from PCA
I am trying to scatter plot the 2 features resulting from the PCA in spark ml library.
To be more precise I am trying to convert result into something like this:
_________
id | X | Y
__________
1 |0....
0
votes
1
answer
247
views
Functional way to build a matrix from the list in scala
I've asked this question on https://users.scala-lang.org/ but haven't got a concrete answer yet. I am given a vector v and I would like to construct a matrix m based on this vector according to the ...
- 367
0
votes
1
answer
178
views
How to convert a DataFrame to an Array of dense vectors?
How would I convert the following DataFrame
val df = Seq(
(5.0, 1.0, 1.0, 3.0, 7.0),
(2.0, 0.0, 3.0, 4.0, 5.0),
(4.0, 0.0, 0.0, 6.0, 7.0)).toDF("m1", "m2", "m3", &...
- 455
1
vote
2
answers
113
views
How do I use the forall loop to check if all rows have the same number of columns in a Vector in Scala?
So I have a generic vector: 1:vec: Vector[Vector[T]]
Now I wanna use the require and forall to check if the length of each row is the same.
This is how far I've gotten:
2:require(vec.forall(row => ...
- 852
0
votes
1
answer
560
views
row to vector in scala spark
I have a row that is obtained in the following way:
val row_name = df.collect()(i)
how can I convert this row to a type vector so that it can be passed to fromML() as follows ?
val vector_name=org....
- 309
0
votes
0
answers
40
views
Data structure that allows efficient equality checks for closely related sequences (common subsequences)
I'm looking for a data structure that I can use for Snapshot (a sequence) in the following example:
val oldSnapshot = Snapshot(3, 2, 1)
val newSnapshot = 4 +: (oldSnapshot dropRight 1) // basically a ...
- 11.2k
1
vote
2
answers
1k
views
Performance : Vector vs ArrayBuffer vs Array
Scala 2.11.4 -
While trying to solve this problem "Sliding Window Maximum", I wrote this code :
def slidingMaximum(A: Array[Int], B: Int): Array[Int] = {
var ans = Vector[Int]()
...
- 13.7k
0
votes
1
answer
90
views
Operation on normalVectorRDD
I want to create an RDD[Vector] with my own mean and my own sigma, i have done this :
val mean = Random.nextInt(100)
val sigma = 2
val data: RDD[Vector] = RandomRDDs.normalVectorRDD(sc, numRows = 180, ...
- 101
1
vote
2
answers
278
views
Scala append value to multiple vector
I create a multiple vector like this:
val a = Vector.fill(3,0)(0)
It outputs:
Vector(Vector(), Vector(), Vector(), Vector(), Vector(), Vector())
I want to append an integer value into the first ...
- 11
0
votes
1
answer
334
views
How to map over a Spark Vector?
I have a mllib.linalg.Vector in Scala containing Double values in range of (-1; 1). I would like to multiply all of the values by, let's say, 100.
For example I'd like to convert [0.5, 0.3, -0.1] to [...
- 6,849
0
votes
1
answer
188
views
Concrete and abstract Vector classes
I went trough scaladoc and found something that I find strange and I cannot explain.
There is the
sealed abstract class Vector
with its companion object Vector.
Looking through Vector.scala it ...
