In my java code I am using a method, let's call foo()
, that returns a scala.Double[]
.
scala.Double[] arr = foo();
I want to sum up arr
into a scala.Double
, but am having trouble. I've found that doing any kind of math operation on scala.Double
s gets me an error message from my IDE:
arr[0] + arr[1];
arr[0] * arr[1];
//etc
get me messages like
Operator '+' cannot be applied to 'scala.Double', 'scala.Double'
How can I do math operations on scala.Double
s within java code? (alternatively, is there another way to sum up a scala.Double[]
within java code?)
It's not clear how you got scala.Double[]
in Java. If you have Array[Double]
in Scala, it's seen in Java as double[]
, not scala.Double[]
.
Anyway, if you have scala.Double[]
in Java
public class App {
public static scala.Double[] arr = foo();
}
then it's seen in Scala also as Array[scala.Double]
object App1 {
val arr1: Array[Double] = App.arr
}
and then the latter is seen back in Java as double[]
public class App {
public static scala.Double[] arr = foo();
public static double[] arr2 = App1.arr1();
}
Then you can do arr2[0] + arr2[1]
, arr2[0] * arr2[1]
...
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