Apache Spark - A unified analytics engine for large-scale data processing
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Felix Cheung f4767bcc7a [SPARK-16310][SPARKR] R na.string-like default for csv source
## What changes were proposed in this pull request?

Apply default "NA" as null string for R, like R read.csv na.string parameter.

https://stat.ethz.ch/R-manual/R-devel/library/utils/html/read.table.html
na.strings = "NA"

An user passing a csv file with NA value should get the same behavior with SparkR read.df(... source = "csv")

(couldn't open JIRA, will do that later)

## How was this patch tested?

unit tests

shivaram

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #13984 from felixcheung/rcsvnastring.
2016-07-07 15:21:57 -07:00
.github [MINOR][MAINTENANCE] Fix typo for the pull request template. 2016-02-24 00:45:31 -08:00
assembly [SPARK-14925][BUILD] Re-introduce 'unused' dependency so that published POMs are flattened 2016-04-26 15:14:17 -07:00
bin [SPARK-16399][PYSPARK] Force PYSPARK_PYTHON to python 2016-07-07 11:31:10 +01:00
build [SPARK-14279][BUILD] Pick the spark version from pom 2016-06-06 09:42:50 -07:00
common [SPARK-16021] Fill freed memory in test to help catch correctness bugs 2016-07-06 16:30:25 -07:00
conf [SPARK-15806][DOCUMENTATION] update doc for SPARK_MASTER_IP 2016-06-12 14:25:48 +01:00
core [SPARK-15885][WEB UI] Provide links to executor logs from stage details page in UI 2016-07-07 00:02:39 -07:00
data [GRAPHX][EXAMPLES] move graphx test data directory and update graphx document 2016-07-02 08:40:23 +01:00
dev [SPARK-15975] Fix improper Popen retcode code handling in dev/run-tests 2016-06-16 14:18:58 -07:00
docs [MESOS] expand coarse-grained mode docs 2016-07-06 15:02:45 -07:00
examples [SPARK-16260][ML][EXAMPLE] PySpark ML Example Improvements and Cleanup 2016-07-03 23:23:02 -07:00
external [SPARK-16212][STREAMING][KAFKA] apply test tweaks from 0-10 to 0-8 as well 2016-07-06 16:21:41 -07:00
graphx [GRAPHX][EXAMPLES] move graphx test data directory and update graphx document 2016-07-02 08:40:23 +01:00
launcher [MINOR] Fix Java Lint errors introduced by #13286 and #13280 2016-06-08 14:51:00 +01:00
licenses [MINOR][BUILD] Add modernizr MIT license; specify "2014 and onwards" in license copyright 2016-06-04 21:41:27 +01:00
mllib [SPARK-16372][MLLIB] Retag RDD to tallSkinnyQR of RowMatrix 2016-07-07 11:28:04 +01:00
mllib-local [MINOR] Fix Typos 'an -> a' 2016-06-06 09:35:47 +01:00
project [SPARK-16021] Fill freed memory in test to help catch correctness bugs 2016-07-06 16:30:25 -07:00
python [MINOR][PYSPARK][DOC] Fix wrongly formatted examples in PySpark documentation 2016-07-06 10:45:51 -07:00
R [SPARK-16310][SPARKR] R na.string-like default for csv source 2016-07-07 15:21:57 -07:00
repl [SPARK-16125][YARN] Fix not test yarn cluster mode correctly in YarnClusterSuite 2016-06-24 08:28:32 +01:00
sbin [SPARK-15806][DOCUMENTATION] update doc for SPARK_MASTER_IP 2016-06-12 14:25:48 +01:00
sql [SPARK-16415][SQL] fix catalog string error 2016-07-07 11:08:06 -07:00
streaming [SPARK-16129][CORE][SQL] Eliminate direct use of commons-lang classes in favor of commons-lang3 2016-06-24 10:35:54 +01:00
tools [MINOR][DOCS] Use multi-line JavaDoc comments in Scala code. 2016-04-02 17:50:40 -07:00
yarn [SPARK-16095][YARN] Yarn cluster mode should report correct state to SparkLauncher 2016-07-01 15:51:21 -07:00
.gitattributes [SPARK-3870] EOL character enforcement 2014-10-31 12:39:52 -07:00
.gitignore [SPARK-16128][SQL] Allow setting length of characters to be truncated to, in Dataset.show function. 2016-06-28 17:11:06 +05:30
.travis.yml [SPARK-15207][BUILD] Use Travis CI for Java Linter and JDK7/8 compilation test 2016-05-10 21:04:22 +01:00
CONTRIBUTING.md [SPARK-6889] [DOCS] CONTRIBUTING.md updates to accompany contribution doc updates 2015-04-21 22:34:31 -07:00
LICENSE [MINOR][BUILD] Add modernizr MIT license; specify "2014 and onwards" in license copyright 2016-06-04 21:41:27 +01:00
NOTICE [MINOR][BUILD] Add modernizr MIT license; specify "2014 and onwards" in license copyright 2016-06-04 21:41:27 +01:00
pom.xml [SPARK-16021][TEST-MAVEN] Fix the maven build 2016-07-06 22:48:05 -07:00
README.md [SPARK-15821][DOCS] Include parallel build info 2016-06-14 13:59:01 +01:00
scalastyle-config.xml [SPARK-16129][CORE][SQL] Eliminate direct use of commons-lang classes in favor of commons-lang3 2016-06-24 10:35:54 +01:00

Apache Spark

Spark is a fast and general cluster computing system for Big Data. It provides high-level APIs in Scala, Java, Python, and R, and an optimized engine that supports general computation graphs for data analysis. It also supports a rich set of higher-level tools including Spark SQL for SQL and DataFrames, MLlib for machine learning, GraphX for graph processing, and Spark Streaming for stream processing.

http://spark.apache.org/

Online Documentation

You can find the latest Spark documentation, including a programming guide, on the project web page and project wiki. This README file only contains basic setup instructions.

Building Spark

Spark is built using Apache Maven. To build Spark and its example programs, run:

build/mvn -DskipTests clean package

(You do not need to do this if you downloaded a pre-built package.)

You can build Spark using more than one thread by using the -T option with Maven, see "Parallel builds in Maven 3". More detailed documentation is available from the project site, at "Building Spark". For developing Spark using an IDE, see Eclipse and IntelliJ.

Interactive Scala Shell

The easiest way to start using Spark is through the Scala shell:

./bin/spark-shell

Try the following command, which should return 1000:

scala> sc.parallelize(1 to 1000).count()

Interactive Python Shell

Alternatively, if you prefer Python, you can use the Python shell:

./bin/pyspark

And run the following command, which should also return 1000:

>>> sc.parallelize(range(1000)).count()

Example Programs

Spark also comes with several sample programs in the examples directory. To run one of them, use ./bin/run-example <class> [params]. For example:

./bin/run-example SparkPi

will run the Pi example locally.

You can set the MASTER environment variable when running examples to submit examples to a cluster. This can be a mesos:// or spark:// URL, "yarn" to run on YARN, and "local" to run locally with one thread, or "local[N]" to run locally with N threads. You can also use an abbreviated class name if the class is in the examples package. For instance:

MASTER=spark://host:7077 ./bin/run-example SparkPi

Many of the example programs print usage help if no params are given.

Running Tests

Testing first requires building Spark. Once Spark is built, tests can be run using:

./dev/run-tests

Please see the guidance on how to run tests for a module, or individual tests.

A Note About Hadoop Versions

Spark uses the Hadoop core library to talk to HDFS and other Hadoop-supported storage systems. Because the protocols have changed in different versions of Hadoop, you must build Spark against the same version that your cluster runs.

Please refer to the build documentation at "Specifying the Hadoop Version" for detailed guidance on building for a particular distribution of Hadoop, including building for particular Hive and Hive Thriftserver distributions.

Configuration

Please refer to the Configuration Guide in the online documentation for an overview on how to configure Spark.