You can also replace column values from thepython dictionary (map). In the below example, we replace the string value of thestatecolumn with the full abbreviated name from a dictionarykey-value pair, in order to do so I usePySpark map() transformation to loop through each row of DataFrame....
format(column_name)) -- Example with the column types for column_name, column_type in dataset.dtypes: -- Replace all columns values by "Test" dataset = dataset.withColumn(column_name, F.lit("Test")) 12. Iteration Dictionaries # Define a dictionary my_dictionary = { "dog": "Alice",...
1、 agg(expers:column*) 返回dataframe类型 ,同数学计算求值 df.agg(max("age"), avg("salary")) df.groupBy().agg(max("age"), avg("salary")) 2、 agg(exprs: Map[String, String]) 返回dataframe类型 ,同数学计算求值 map类型的 df.agg(Map("age" -> "max", "salary" -> "avg")) df....
when(condition, value1).otherwise(value2)联合使用:那么:当满足条件condition的指赋值为values1,不满足条件的则赋值为values2.otherwise表示,不满足条件的情况下,应该赋值为啥。 demo1: 1 2 3 4 5 6 7 8 >>> from pyspark.sql import functions as F >>> df.select(df.name, F.when(df.age > 4, ...
when(condition, value1).otherwise(value2),意为:当满足条件condition的值时赋值为values1,不满足条件的则赋值为values2,otherwise表示,不满足条件的情况下,应该赋值何值。 例: from pyspark.sql import functions as F df.select(df.customerID,F.when(df.gender=="Male","1").when(df.gender=="Female",...
笔者最近需要使用pyspark进行数据整理,于是乎给自己整理一份使用指南。pyspark.dataframe跟pandas的差别还是挺大的。 文章目录 1、--- 查 --- --- 1.1 行元素查询操作 --- **像SQL那样打印列表前20元素** **以树的形式打印概要** **获取头几行到...
@column_condition_partial(engine=SparkDFExecutionEngine) def _spark(cls, column, ts_formats, **kwargs): return column.isin([3]) # need to replace the abov 浏览4提问于2021-11-19得票数 0 回答已采纳 7回答 如何将星火流数据转换为星火DataFrame 、、 到目前为止,Spark还没有为流数据创建Da...
dfs.createOrReplaceTempView("df_sql") dfs=spark.sql("SELECT DISTINCT Name FROM df_sql") print("The distinct values in the column are:") dfs.show() spark.sparkContext.stop() Output: The input dataframe is: +---+---+---+---+ | Name|Maths|Physics|Chemistry...
df_renamed = df.withColumnRenamed(“name to update”, “new_column”) Conclusion Here, I have covered updating a PySpark DataFrame Column values, updating values based on condition, changing the data type, and updating using SQL expression. ...
Fill NULL values in specific columns Fill NULL values with column average Fill NULL values with group average Unpack a DataFrame's JSON column to a new DataFrame Query a JSON column Sorting and Searching Filter a column using a condition Filter based on a specific column value Filter based on...