pyspark UDF 输出空白

Question

我对我的 UDF 函数有疑问：我有一个数据：raw data

我正在编写代码以将名称列大写:(输入 john doe->putout: John Doe)

@F.udf
def coverCase(Str):
    resStr=""
    arr=str.split(" ")
    for x in arr:
        resStr=resStr+ x[0:1].upper()+x[1:len(x)]+" "
    
    return resStr
df.select(coverCase("name")).show()

我没有输出 output screen shot

Answer 1

from pyspark.sql import functions as F
from pyspark.sql.functions import col

df = spark.createDataFrame([(1,"john doe", 21)], ("id", "name", "age"))

@F.udf
def convertCase(str):
    resStr=""
    arr = str.split(" ")
    for x in arr:
       resStr= resStr + x[0:1].upper() + x[1:len(x)] + " "
    return resStr

df.select(convertCase(col("name"))).show()

+-----------------+
|convertCase(name)|
+-----------------+
|        John Doe |
+-----------------+

pyspark UDF 输出空白

pyspark UDF output blank

user-defined-functions

pyspark