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Diffstat (limited to 'docs/streaming-programming-guide.md')
| -rw-r--r-- | docs/streaming-programming-guide.md | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/docs/streaming-programming-guide.md b/docs/streaming-programming-guide.md index 677f5ff7be..4d1932bc8c 100644 --- a/docs/streaming-programming-guide.md +++ b/docs/streaming-programming-guide.md @@ -798,7 +798,7 @@ Some of the common ones are as follows. <td> <b>reduce</b>(<i>func</i>) </td> <td> Return a new DStream of single-element RDDs by aggregating the elements in each RDD of the source DStream using a function <i>func</i> (which takes two arguments and returns one). - The function should be associative so that it can be computed in parallel. </td> + The function should be associative and commutative so that it can be computed in parallel. </td> </tr> <tr> <td> <b>countByValue</b>() </td> @@ -1072,7 +1072,7 @@ said two parameters - <i>windowLength</i> and <i>slideInterval</i>. <tr> <td> <b>reduceByWindow</b>(<i>func</i>, <i>windowLength</i>, <i>slideInterval</i>) </td> <td> Return a new single-element stream, created by aggregating elements in the stream over a - sliding interval using <i>func</i>. The function should be associative so that it can be computed + sliding interval using <i>func</i>. The function should be associative and commutative so that it can be computed correctly in parallel. </td> </tr> |