title: Error initializing SparkContext: A master URL must be set in your configuration
body: <p>I used <a href="https://github.com/prashantprakash/KDDDataResearch/blob/master/Code/approach1Plus2/src/main/scala/PCA.scala" rel="noreferrer">this code</a></p>
  
  <p>My error is:</p>
  
  <pre><code>Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
  
  17/02/03 20:39:24 INFO SparkContext: Running Spark version 2.1.0
  
  17/02/03 20:39:25 WARN NativeCodeLoader: Unable to load native-hadoop 
  library for your platform... using builtin-java classes where applicable
  
  17/02/03 20:39:25 WARN SparkConf: Detected deprecated memory fraction 
  settings: [spark.storage.memoryFraction]. As of Spark 1.6, execution and  
  storage memory management are unified. All memory fractions used in the old 
  model are now deprecated and no longer read. If you wish to use the old 
  memory management, you may explicitly enable `spark.memory.useLegacyMode` 
  (not recommended).
  
  17/02/03 20:39:25 ERROR SparkContext: Error initializing SparkContext.
  
  org.apache.spark.SparkException: A master URL must be set in your 
  configuration
  at org.apache.spark.SparkContext.&lt;init&gt;(SparkContext.scala:379)
  at PCA$.main(PCA.scala:26)
  at PCA.main(PCA.scala)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:498)
  at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)
  
  17/02/03 20:39:25 INFO SparkContext: Successfully stopped SparkContext
  Exception in thread "main" org.apache.spark.SparkException: A master URL must be set in your configuration
  at org.apache.spark.SparkContext.&lt;init&gt;(SparkContext.scala:379)
  at PCA$.main(PCA.scala:26)
  at PCA.main(PCA.scala)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at 
     sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  at   
      sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  
  at java.lang.reflect.Method.invoke(Method.java:498)
  at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)
  
  Process finished with exit code 1
  </code></pre>