In this short "How to" article, we will learn how to change the data type of a column in Pandas and PySpark DataFrames.
In this code snippet, we create a DataFramedfwith two columns: “name” of type StringType and “age” of type StringType. Let’s say we want to change the data type of the “age” column from StringType to IntegerType. We can do this using thecast()function: df=df.withColumn("age...
# Don't change this query query = "SELECT origin, dest, COUNT(*) as N FROM flights GROUP BY origin, dest" # Run the query flight_counts = spark.sql(query) # Convert the results to a pandas DataFrame pd_counts = flight_counts.toPandas() # Print the head of pd_counts print(pd_co...
(1)列操作 # add a new column data = data.withColumn("newCol",df.oldCol+1) # replace the old column data = data.withColumn("oldCol",newCol) # rename the column data.withColumnRenamed("oldName","newName") # change column data type data.withColumn("oldColumn", data.oldColumn.cast("in...
# Don't change this queryquery="SELECT origin, dest, COUNT(*) as N FROM flights GROUP BY origin, dest"# Run the queryflight_counts=spark.sql(query)# Convert the results to a pandas DataFramepd_counts=flight_counts.toPandas()# Print the head of pd_countsprint(pd_counts.head()) ...
These arguments can either be the column name as a string (one for each column) or a column object (using the df.colName syntax). When you pass a column object, you can perform operations like addition or subtraction on the column to change the data contained in it, much like inside ...
This question is also being asked as: Python combining two columns. People have also asked for: Selecting multiple columns in a DataFrame. Change column type in Pandas. Creating an empty DataFrame, then filling it. Rate this article No votes so far! Be the first to rate this post. ...
In some cases you may want to change the data type for one or more of the columns in your DataFrame. To do this, use the cast method to convert between column data types. The following example shows how to convert a column from an integer to string type, using the col method to ...
sqlContext.sql("insert into bi.bike_changes_2days_a_d partition(dt='%s') select citycode,biketype,detain_bike_flag,bike_tag_onday,bike_tag_yesterday,bike_num from bike_change_2days"%(date)) 写入集群非分区表 1 df_spark.write.mode("append").insertInto('bi.pesudo_bike_white_list') ...
selects.append(from_json(column, schema).getItem('root').alias(column)) else: selects.append(column) return df.select(*selects) 函数complex_dtypes_to_json将一个给定的Spark数据帧转换为一个新的数据帧,其中所有具有复杂类型的列都被JSON字符串替换。除了转换后的数据帧外,它还返回一个带有列名及其转...