SPARK_HOME=_find_spark_home()#LaunchthePy4jgatewayusingSpark'sruncommandsothatwepickupthe#properclasspathandsettingsfromspark-env.shon_windows=platform.system()=="Windows"script="./bin/spark-submit.cmd"ifon_windowselse"./bin/spark-submit"command=[os.path.join(SPARK_HOME,script)] 然后创建 Java...
import pyspark.sql.functions as Ffrom pyspark.sql.types import * defsomefunc(value):if value < 3:return 'low'else:return 'high' #convert to a UDF Function by passing in the function and return type of functionudfsomefunc = F.udf(somefunc, StringType())ratings_with_high_low = ratings....
if value < 3: return 'low' else: return 'high' #convert to a UDF Function by passing in the function and return type of function udfsomefunc = F.udf(somefunc, StringType()) ratings_with_high_low = ratings.withColumn("high_low", udfsomefunc("rating")) ratings_with_high_low.show()...
我们创建了一个简单的 Python 函数,它根据移动品牌返回价格范围的类别: [In]:defprice_range(brand):ifbrandin['Samsung','Apple']:return'High Price'elifbrand =='MI':return'Mid Price'else:return'Low Price' 在下一步中,我们创建一个 UDF (brand_udf),它使用这个函数并捕获它的数据类型,以便将这个转换...
本书的代码包也托管在 GitHub 上,网址为github.com/PacktPublishing/Hands-On-Big-Data-Analytics-with-PySpark。如果代码有更新,将在现有的 GitHub 存储库上进行更新。 我们还有其他代码包,来自我们丰富的书籍和视频目录,可在github.com/PacktPublishing/上找到。请查看!
(day): if day==None: return datetime.datetime.now() else: return datetime.datetime.strptime(day,"%y-%m-%d") # 返回类型为字符串类型 udfday = udf(today, DateType()) df.withColumn('date', udfday(df.date)) # 对每行的指定列进行变换 print(df.show(3)) # 填充缺失值 df=df.fillna('...
随机抽样有两种方式,一种是在HIVE里面查数随机;另一种是在pyspark之中。 HIVE里面查数随机 代码语言:javascript 代码运行次数:0 运行 AI代码解释 sql="select * from data order by rand() limit 2000" pyspark之中 代码语言:javascript 代码运行次数:0 ...
if(), else() 第7个问题 What will be the output of the following statement? ceil(2.33, 4.6, 1.09, 10.9) (2, 4, 1, 0) (3, 5, 2, 11) (2.5, 4.5, 1.5, 10.5) (0,0,0,10) 第8 个问题 Which of the following is the suggested way to visualize big data that has been loaded ...
# proper classpath and settings from spark-env.sh on_windows=platform.system()=="Windows"script="./bin/spark-submit.cmd"ifon_windowselse"./bin/spark-submit"command=[os.path.join(SPARK_HOME,script)] 然后创建 JavaGateway 并 import 一些关键的 class: 代码语言:javascript 代码运行次数:0 运行 A...
SPARK_HOME = _find_spark_home()# Launch the Py4j gateway using Spark's run command so that we pick up the# proper classpath and settings from spark-env.shon_windows = platform.system() =="Windows"script ="./bin/spark-submit.cmd"ifon_windowselse"./bin/spark-submit"command = [os.pat...