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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