如何撰写一个高效的bash脚本来修改一个csv档案-编程知识-白鹭情

我创建了一个脚本来修改 CSV 档案，但它无法正常作业：

在awk -F, 'NR==1|不打印头，但第二排。
即使其中只指定了一些列，while read V0 V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V14 V15 V16它也会打印出 csv 的所有列。

一些示例资料：

 COUNTRY NAME,YEAR,LIFE LADDER,LOG GDP PER CAPITA,SOCIAL SUPPORT,HEALTHY LIFE EXPECTANCY AT BIRTH,FREEDOM TO MAKE LIFE CHOICES,GENEROSITY,PERCEPTIONS OF CORRUPTION,POSITIVE AFFECT,NEGATIVE AFFECT,CONFIDENCE IN NATIONAL GOVERNMENT,DEMOCRATIC QUALITY,DELIVERY QUALITY,STANDARD DEVIATION OF LADDER BY COUNTRY-YEAR,STANDARD DEVIATION/MEAN OF LADDER BY COUNTRY-YEAR,GINI INDEX (WORLD BANK ESTIMATE),GINI INDEX (WORLD BANK ESTIMATE) AVERAGE 2000-16","GINI OF HOUSEHOLD INCOME REPORTED IN GALLUP BY WP5-YEAR","MOST PEOPLE CAN BE TRUSTED GALLUP","MOST PEOPLE CAN BE TRUSTED WVS ROUND 1981-1984","MOST PEOPLE CAN BE TRUSTED WVS ROUND 1989-1993","MOST PEOPLE CAN BE TRUSTED WVS ROUND 1994-1998","MOST PEOPLE CAN BE TRUSTED WVS ROUND 1999-2004","MOST PEOPLE CAN BE TRUSTED WVS ROUND 2005-2009","MOST PEOPLE CAN BE TRUSTED WVS ROUND 2010-2014"
AFGHANISTAN,2008,3.72,7.16,0.45,50.79,0.71,0.17,0.88,0.51,0.25,0.61,-1.92,-1.65,1.77,0.47,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2009,4.40,7.33,0.55,51.20,0.67,0.20,0.85,0.58,0.23,0.61,-2.04,-1.63,1.72,0.39,NULL,NULL,0.44,0.28,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2010,4.75,7.38,0.53,51.59,0.60,0.13,0.70,0.61,0.27,0.29,-1.99,-1.61,1.87,0.39,NULL,NULL,0.32,0.27,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2011,3.83,7.41,0.52,51.91,0.49,0.17,0.73,0.61,0.26,0.30,-1.91,-1.61,1.78,0.46,NULL,NULL,0.33,NULL,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2012,3.78,7.51,0.52,52.24,0.53,0.24,0.77,0.71,0.26,0.43,-1.84,-1.40,1.79,0.47,NULL,NULL,0.34,NULL,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2013,3.57,7.52,0.48,52.56,0.57,0.07,0.82,0.62,0.27,0.48,-1.87,-1.40,1.22,0.34,NULL,NULL,0.30,NULL,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2014,3.13,7.51,0.52,52.88,0.50,0.11,0.87,0.53,0.37,0.40,-1.77,-1.31,1.39,0.44,NULL,NULL,0.41,NULL,NULL,NULL,NULL,NULL,NULL,
AFGHANISTAN,2015,3.98,7.50,0.52,53.20,0.38,0.08,0.88,0.55,0.33,0.26,-1.84,-1.29,2.16,0.54,NULL,NULL,0.59,NULL,NULL,NULL,NULL,NULL,NULL,

这是我的脚本：

#!/usr/bin/env bash

INPUT=./happiness.csv.1
OLDIFS=$IFS
IFS=','
[ ! -f $INPUT ] && { echo "$INPUT file not found"; exit 99; }


while read V0 V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V14 V15 V16 

do
      awk -F, 'NR==1 || /^[A-Z,a-z]*,2018/' | 
      grep '^.*-.*$' 
                                                
done < $INPUT

这是输出：

> AFGHANISTAN,2008,3.72,7.16,0.45,50.79,0.71,0.17,0.88,0.51,0.25,0.61,-1.92,-1.65,1.77,0.47,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,
> AFGHANISTAN,2018,2.69,7.49,0.50,52.59,0.37,-0.08,0.92,0.42,0.40,0.36,NULL,NULL,1.40,0.52,NULL,NULL,0.29,NULL,NULL,NULL,NULL,NULL,NULL,
> ALGERIA,2018,5.04,9.55,0.79,65.90,0.58,-0.17,0.75,0.59,0.29,NULL,NULL,NULL,1.97,0.39,NULL,0.27,0.66,NULL,NULL,NULL,NULL,0.10,NULL,0.17
> ARGENTINA,2018,5.79,9.80,0.89,68.80,0.84,-0.20,0.85,0.82,0.32,0.26,NULL,NULL,2.47,0.42,NULL,0.46,0.40,NULL,0.27,0.22,0.17,0.15,0.17,0.19
> ARMENIA,2018,5.06,9.11,0.81,66.90,0.80,-0.14,0.67,0.58,0.45,0.67,NULL,NULL,2.10,0.41,NULL,0.31,0.40,NULL,NULL,NULL,0.23,NULL,NULL,0.10
> AZERBAIJAN,2018,5.16,9.67,0.78,65.5,0.77,-0.25,0.56,0.59,0.19,0.83,NULL,NULL,1.86,0.36,NULL,0.21,0.26,NULL,NULL,NULL,0.19,NULL,NULL,0.14
> BANGLADESH,2018,4.49,8.22,0.70,64.30,0.90,-0.03,0.70,0.54,0.36,0.83,NULL,NULL,2.15,0.47,NULL,0.32,0.36,NULL,NULL,NULL,0.20,0.23,NULL,
> BELARUS,2018,5.23,9.77,0.90,66.09,0.64,-0.18,0.71,0.45,0.23,0.42,NULL,NULL,1.69,0.32,NULL,0.28,0.29,NULL,NULL,0.25,0.22,NULL,NULL,0.32
> BELGIUM,2018,6.89,10.67,0.92,72,0.80,-0.12,0.63,0.74,0.25,0.44,NULL,NULL,1.54,0.22,NULL,0.28,0.29,NULL,NULL,NULL,NULL,NULL,NULL,
> BOLIVIA,2018,5.91,8.86,0.82,63.59,0.86,-0.08,0.78,0.74,0.38,0.39,NULL,NULL,2.20,0.37,NULL,0.52,0.45,NULL,NULL,NULL,NULL,NULL,NULL,
> BOTSWANA,2018,3.46,9.68,0.79,58.90,0.81,-0.25,0.80,0.72,0.26,0.71,NULL,NULL,2.63,0.76,NULL,0.62,0.61,NULL,NULL,NULL,NULL,NULL,NULL,
> BRAZIL,2018,6.19,9.55,0.88,66.40,0.75,-0.12,0.76,0.74,0.34,0.16,NULL,NULL,2.63,0.42,NULL,0.54,0.42,NULL,NULL,0.06,NULL,NULL,0.09,0.07
> BULGARIA,2018,5.09,9.87,0.92,66.80,0.72,-0.17,0.95,0.63,0.18,0.21,NULL,NULL,2.03,0.39,NULL,0.35,0.34,NULL,NULL,NULL,0.23,NULL,0.19,
> BURUNDI,2018,3.77,6.54,0.48,53.40,0.64,-0.01,0.59,0.66,0.36,NULL,NULL,NULL,2.81,0.74,NULL,0.36,0.68,NULL,NULL,NULL,NULL,NULL,NULL,
> CHILE,2018,6.43,10.06,0.89,69.90,0.78,-0.07,0.81,0.83,0.27,0.33,NULL,NULL,2.15,0.33,NULL,0.49,0.43,NULL,NULL,0.22,0.21,0.22,0.12,0.12
> CHINA,2018,5.13,9.69,0.78,69.30,0.89,-0.17,NULL,0.85,0.18,NULL,NULL,NULL,2.26,0.44,NULL,0.42,0.53,NULL,NULL,0.59,0.50,0.54,0.49,0.61

谁能看到我做错了什么？

我可以将 awk 陈述句交换为：

while read V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 ....

do
      if [[ "$V2" = "2018" ]];then

uj5u.com热心网友回复：

根据您代码的当前意图，这是我可以建议的修改：

#!/usr/bin/env bash

INPUT=./happiness.csv.1
[[ -f $INPUT ]] || { echo "$INPUT file not found"; exit 99; }
awk -F, 'NR == 1 || $2 == "2018" && /-/' "$INPUT"