Bash 填充csv的列

我有一个csv文件，其中包含大量csv分离的数据行。我想找到行的最大长度，然后需要在新列中打印NO

file.csv

1,2,3,4,
1,4,7,8,9,10,11,13
1,2,
1,1,2,4,5,6,7,8,9,10,11
abc,def,ghi,jkl

预期结果

1,2,3,4,,,,,,,,,,,,,,,,N0
1,4,7,8,9,10,11,13,,,,,NO
1,2,,,,,,,,,,,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,1,NO
abc,def,ghi,jkl,,,,,,,,NO

获得的产出

1,2,3,4,NO
1,4,7,8,9,10,11,13,NO
1,2,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,NO

如果行必须具有相同的大小：

awk -F, 'BEGIN{m=0}
{if(length($0)>m)m=length($0);ar[NR]=$0;ars[NR]=length($0);}
END{for(i=1;i<=NR;i++)
       {for(j=ars[i];j<m;j++)
           {ar[i]=ar[i]","}ar[i]=ar[i]"NO";
                           print ar[i]}}' <<<'1,2,3,4,
1,4,7,8,9,10,11,13
1,2,
1,1,2,4,5,6,7,8,9,10,11,12
abc,def,ghi,jkl
a,b'

---

如果要在最大长度线后加逗号，则循环运行到m+1

您需要读取文件两次，一次获取最大列数，一次打印输出：

awk -F, 'NR==FNR{if(m<=NF)m=NF;next} # Runs only on first iteration
         {printf "%s",$0;for(i=0;i<=(m-NF);i++)printf ",";print "NO"}' file file

                                                      filename twice -----^

---

很难想象为什么要用逗号填充行，因此我认为您真正想要的是使每行具有相同数量的字段：

$ awk 'BEGIN{FS=OFS=","} NR==FNR{m=(m>NF?m:NF);next} {$(m+1)="NO"} 1' file file
1,2,3,4,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,NO
1,2,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,,,,,,,,NO

下面是你说的你想要的：

$ awk '{n=length()} NR==FNR{m=(m>n?m:n);next} {p=sprintf("%*s",m-n+1,""); gsub(/ /,",",p); $0=$0 p "NO"} 1' file file
1,2,3,4,,,,,,,,,,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,,,NO
1,2,,,,,,,,,,,,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,,,,,,,,,NO

---

每一行是用

，

填充还是每一行的列数相同？您声称从

cat file | cat>file.csv；echo NO>>file.csv

令人惊讶。你必须有魔法版的

cat

和

echo

，可以猜出你的愿望。

1,2,3,4,,,,,,,,,,,,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,,,,,NO
1,2,,,,,,,,,,,,,,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,12NO
abc,def,ghi,jkl,,,,,,,,,,,NO
a,b,,,,,,,,,,,,,,,,,,,,,,,NO

awk -F, 'NR==FNR{if(m<=NF)m=NF;next} # Runs only on first iteration
         {printf "%s",$0;for(i=0;i<=(m-NF);i++)printf ",";print "NO"}' file file

                                                      filename twice -----^

1,2,3,4,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,NO
1,2,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,,,,,,,,NO

$ awk 'BEGIN{FS=OFS=","} NR==FNR{m=(m>NF?m:NF);next} {$(m+1)="NO"} 1' file file
1,2,3,4,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,NO
1,2,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,,,,,,,,NO

$ awk '{n=length()} NR==FNR{m=(m>n?m:n);next} {p=sprintf("%*s",m-n+1,""); gsub(/ /,",",p); $0=$0 p "NO"} 1' file file
1,2,3,4,,,,,,,,,,,,,,,,,NO
1,4,7,8,9,10,11,13,,,,,,NO
1,2,,,,,,,,,,,,,,,,,,,,,NO
1,1,2,4,5,6,7,8,9,10,11,NO
abc,def,ghi,jkl,,,,,,,,,NO