linux - 如何替换 csv 所有列中的特定值？

Question

我有这个数据:

111,24,1,\N,\N,[],aa
222,25,2,\N,\N,[],bb
333,26,3,\N,\N,[],\N

我想使用 awk 替换第 4 和第 5 列中的所有 \N 值。

我写了这个，但不确定我的方法是否正确:

awk -F "," '{print $1 "," $2 "," $3 "," $4/ "," $5/ "," $6 "," $7}'

这个解决方案不灵活。如果我有 100 列怎么办？

更新

预期输出:

111,24,1,4.3,2.1,[],aa
222,25,2,4.3,2.1,[],bb
333,26,3,4.3,2.1,[],\N

Answer 1

我会写:

awk '
    BEGIN {FS = OFS = ","}
    $4 == "\\N" {$4 = 4.3}
    $5 == "\\N" {$5 = 2.1}
    {print}
' file

或者，如果你的实际情况更复杂，比如

awk '
    BEGIN {
        FS = OFS = ","
        repl[4] = 4.3
        repl[5] = 2.1
        repl[7] = "hello"
    }
    {for (i in repl) if ($i == "\\N") $i = repl[i]}
    {print}
' file