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From Eyal Sharon <e...@scene53.com>
Subject Re: Help with type check
Date Tue, 01 Dec 2015 08:34:31 GMT
Great, That works perfect !!
Also tnx for the links - very helpful

On Tue, Dec 1, 2015 at 12:13 AM, Jakob Odersky <jodersky@gmail.com> wrote:

> Hi Eyal,
>
> what you're seeing is not a Spark issue, it is related to boxed types.
>
> I assume 'b' in your code is some kind of java buffer, where b.getDouble()
> returns an instance of java.lang.Double and not a scala.Double. Hence
> muCouch is an Array[java.lang.Double], an array containing boxed doubles.
>
> To fix your problem, change 'yield b.getDouble(i)' to 'yield
> b.getDouble(i).doubleValue'
>
> You might want to have a look at these too:
> -
> http://stackoverflow.com/questions/23821576/efficient-conversion-of-java-util-listjava-lang-double-to-scala-listdouble
> - https://docs.oracle.com/javase/7/docs/api/java/lang/Double.html
> - http://www.scala-lang.org/api/current/index.html#scala.Double
>
> On 30 November 2015 at 10:13, Eyal Sharon <eyal@scene53.com> wrote:
>
>> Hi ,
>>
>> I have problem with inferring what are the types bug here
>>
>> I have this code fragment . it parse Json to Array[Double]
>>
>>
>>
>>
>>
>>
>> *val muCouch = {  val e = input.filter( _.id=="mu")(0).content()  val b  = e.getArray("feature_mean")
 for (i <- 0 to e.getInt("features") ) yield b.getDouble(i)}.toArray*
>>
>> Now the problem is when I want to create a dense vector  :
>>
>> *new DenseVector(muCouch)*
>>
>>
>> I get the following error :
>>
>>
>> *Error:(111, 21) type mismatch;
>>  found   : Array[java.lang.Double]
>>  required: Array[scala.Double] *
>>
>>
>> Now , I probably get a workaround for that , but I want to get a deeper understanding
 on why it occurs
>>
>> p.s - I do use collection.JavaConversions._
>>
>> Thanks !
>>
>>
>>
>>
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>
>

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