21.forEach.ipynb

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    "# foreach():\n",
    "\n",
    "                        Syntax:    RDD.foreach(<function>)\n",
    "\n",
    "The foreach() action applies a function specified in the function argument, anonymous\n",
    "or named, to all elements of an RDD. Because foreach() is an action rather than a transformation, you can perform functions otherwise not possible or intended in transformations, such as\n",
    "\n",
    "a print() function. Although Python lambda functions don’t allow you to execute a print()\n",
    "statement directly, you can use a named function that executes print() instead. Listing 4.25\n",
    "shows an example of this."
   ]
  },
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   "source": [
    "from pyspark.context import SparkContext\n",
    "from pyspark.sql import SparkSession\n",
    "sc = SparkContext('local')\n",
    "spark = SparkSession(sc)"
   ]
  },
  {
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   "source": [
    "def printfunc(x):\n",
    "    print(x)\n",
    "    \n",
    "licenses = sc.textFile('file:///opt/Spark/licenses')\n",
    "longwords = licenses.flatMap(lambda x: x.split(' ')).filter(lambda x: len(x) > 12)\n",
    "longwords.foreach(lambda x: printfunc(x))\n"
   ]
  }
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