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Diffstat (limited to 'docs/graphx-programming-guide.md')
| -rw-r--r-- | docs/graphx-programming-guide.md | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/docs/graphx-programming-guide.md b/docs/graphx-programming-guide.md index 07be8ba58e..42ab27bf55 100644 --- a/docs/graphx-programming-guide.md +++ b/docs/graphx-programming-guide.md @@ -86,6 +86,12 @@ support the [Bagel API](api/scala/index.html#org.apache.spark.bagel.package) and [Bagel programming guide](bagel-programming-guide.html). However, we encourage Bagel users to explore the new GraphX API and comment on issues that may complicate the transition from Bagel. +## Upgrade Guide from Spark 0.9.1 + +GraphX in Spark {{site.SPARK_VERSION}} contains one user-facing interface change from Spark 0.9.1. [`EdgeRDD`][EdgeRDD] may now store adjacent vertex attributes to construct the triplets, so it has gained a type parameter. The edges of a graph of type `Graph[VD, ED]` are of type `EdgeRDD[ED, VD]` rather than `EdgeRDD[ED]`. + +[EdgeRDD]: api/scala/index.html#org.apache.spark.graphx.EdgeRDD + # Getting Started To get started you first need to import Spark and GraphX into your project, as follows: @@ -145,12 +151,12 @@ the vertices and edges of the graph: {% highlight scala %} class Graph[VD, ED] { val vertices: VertexRDD[VD] - val edges: EdgeRDD[ED] + val edges: EdgeRDD[ED, VD] } {% endhighlight %} -The classes `VertexRDD[VD]` and `EdgeRDD[ED]` extend and are optimized versions of `RDD[(VertexID, -VD)]` and `RDD[Edge[ED]]` respectively. Both `VertexRDD[VD]` and `EdgeRDD[ED]` provide additional +The classes `VertexRDD[VD]` and `EdgeRDD[ED, VD]` extend and are optimized versions of `RDD[(VertexID, +VD)]` and `RDD[Edge[ED]]` respectively. Both `VertexRDD[VD]` and `EdgeRDD[ED, VD]` provide additional functionality built around graph computation and leverage internal optimizations. We discuss the `VertexRDD` and `EdgeRDD` API in greater detail in the section on [vertex and edge RDDs](#vertex_and_edge_rdds) but for now they can be thought of as simply RDDs of the form: @@ -302,7 +308,7 @@ class Graph[VD, ED] { val degrees: VertexRDD[Int] // Views of the graph as collections ============================================================= val vertices: VertexRDD[VD] - val edges: EdgeRDD[ED] + val edges: EdgeRDD[ED, VD] val triplets: RDD[EdgeTriplet[VD, ED]] // Functions for caching graphs ================================================================== def persist(newLevel: StorageLevel = StorageLevel.MEMORY_ONLY): Graph[VD, ED] @@ -908,7 +914,7 @@ val setC: VertexRDD[Double] = setA.innerJoin(setB)((id, a, b) => a + b) ## EdgeRDDs -The `EdgeRDD[ED]`, which extends `RDD[Edge[ED]]` organizes the edges in blocks partitioned using one +The `EdgeRDD[ED, VD]`, which extends `RDD[Edge[ED]]` organizes the edges in blocks partitioned using one of the various partitioning strategies defined in [`PartitionStrategy`][PartitionStrategy]. Within each partition, edge attributes and adjacency structure, are stored separately enabling maximum reuse when changing attribute values. @@ -918,11 +924,11 @@ reuse when changing attribute values. The three additional functions exposed by the `EdgeRDD` are: {% highlight scala %} // Transform the edge attributes while preserving the structure -def mapValues[ED2](f: Edge[ED] => ED2): EdgeRDD[ED2] +def mapValues[ED2](f: Edge[ED] => ED2): EdgeRDD[ED2, VD] // Revere the edges reusing both attributes and structure -def reverse: EdgeRDD[ED] +def reverse: EdgeRDD[ED, VD] // Join two `EdgeRDD`s partitioned using the same partitioning strategy. -def innerJoin[ED2, ED3](other: EdgeRDD[ED2])(f: (VertexId, VertexId, ED, ED2) => ED3): EdgeRDD[ED3] +def innerJoin[ED2, ED3](other: EdgeRDD[ED2, VD])(f: (VertexId, VertexId, ED, ED2) => ED3): EdgeRDD[ED3, VD] {% endhighlight %} In most applications we have found that operations on the `EdgeRDD` are accomplished through the |