Good catch, Daniel. Looks like this is a scala bug, not a spark one. Yet,
spark users got to be careful not using NumericRange.


On Fri, Apr 18, 2014 at 9:05 PM, Daniel Darabos <
daniel.dara...@lynxanalytics.com> wrote:

> To make up for mocking Scala, I've filed a bug (
> https://issues.scala-lang.org/browse/SI-8518) and will try to patch this.
>
>
> On Fri, Apr 18, 2014 at 9:24 PM, Daniel Darabos <
> daniel.dara...@lynxanalytics.com> wrote:
>
>> Looks like NumericRange in Scala is just a joke.
>>
>> scala> val x = 0.0 to 1.0 by 0.1
>> x: scala.collection.immutable.NumericRange[Double] = NumericRange(0.0,
>> 0.1, 0.2, 0.30000000000000004, 0.4, 0.5, 0.6, 0.7, 0.7999999999999999,
>> 0.8999999999999999, 0.9999999999999999)
>>
>> scala> x.take(3)
>> res1: scala.collection.immutable.NumericRange[Double] = NumericRange(0.0,
>> 0.1, 0.2)
>>
>> scala> x.drop(3)
>> res2: scala.collection.immutable.NumericRange[Double] =
>> NumericRange(0.30000000000000004, 0.4, 0.5, 0.6, 0.7, 0.7999999999999999,
>> 0.8999999999999999, 0.9999999999999999)
>>
>> So far so good.
>>
>> scala> x.drop(3).take(3)
>> res3: scala.collection.immutable.NumericRange[Double] =
>> NumericRange(0.30000000000000004, 0.4)
>>
>> Why only two values? Where's 0.5?
>>
>> scala> x.drop(6)
>> res4: scala.collection.immutable.NumericRange[Double] =
>> NumericRange(0.6000000000000001, 0.7000000000000001, 0.8, 0.9)
>>
>> And where did the last value disappear now?
>>
>> You have to approach Scala with a healthy amount of distrust. You're on
>> the right track with toArray.
>>
>>
>> On Fri, Apr 18, 2014 at 8:01 PM, Mark Hamstra <m...@clearstorydata.com>wrote:
>>
>>> Please file an issue: Spark Project 
>>> JIRA<https://issues.apache.org/jira/browse/SPARK>
>>>
>>>
>>>
>>> On Fri, Apr 18, 2014 at 10:25 AM, Aureliano Buendia <
>>> buendia...@gmail.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> I just notices that sc.makeRDD() does not make all values given with
>>>> input type of NumericRange, try this in spark shell:
>>>>
>>>>
>>>> $ MASTER=local[4] bin/spark-shell
>>>>
>>>> scala> sc.makeRDD(0.0 to 1 by 0.1).collect().length
>>>>
>>>> *8*
>>>>
>>>>
>>>> The expected length is 11. This works correctly when lanching spark
>>>> with only one core:
>>>>
>>>>
>>>> $ MASTER=local[1] bin/spark-shell
>>>>
>>>> scala> sc.makeRDD(0.0 to 1 by 0.1).collect().length
>>>>
>>>> *11*
>>>>
>>>>
>>>> This also works correctly when using toArray():
>>>>
>>>> $ MASTER=local[4] bin/spark-shell
>>>>
>>>> scala> sc.makeRDD((0.0 to 1 by 0.1).*toArray*).collect().length
>>>>
>>>> *8*
>>>>
>>>
>>>
>>
>

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