自动将反引号应用于数组[column] spark [英] Apply automatically backquotes to Array [column] spark

问题描述

大家好，我有一个Array [Column]列中包含带有."的名称. character.i知道使用反引号``解决了问题".".如何在select命令中的columnToKeep上自动添加反引号

hello guys i have an Array[Column] the column included name with "." character.i know that using backquotes `` solves the issue of having".".How to add automatically backquotes on columnToKeep in the select command

val df = spark.read.option("header",true).option("inferSchema","false").csv("C:/data.csv")
val columToKeep = df.columns.map(c => stddev(c).as(c))
val new_Data= df.select(columToKeep:_*)//issue here because name contains "."


  Row.Number,Poids,Age,Taille,0M.I,Hmean,Cooc.Param,Ldp.Param,Test.2,Classe.2
0,87,72,160,5,0.6993,2.9421,2.3745,3,4
1,54,70,163,5,0.6301,2.7273,2.2205,3,4
2,72,51,164,5,0.6551,2.9834,2.3993,3,4
3,75,74,170,5,0.6966,2.9654,2.3699,3,4
 column with constant variable 
 expected output
 OM.I,Test.2,Classe.2
5,3,4
5,3,4
5,3,4
5,3,4

谢谢

推荐答案

这可以解决问题

val columToKeep = df.columns.map(c => stddev(c).as(c)).map(x => s"`${x}`")
val new_Data= df.select(columToKeep.head, columToKeep.tail:_*)

尽管如此，我没有达到

stddev

stddev

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