shell - replacing matching columns using sed/awk/

Question

How can I achieve this using awk/sed or any other scripting commands.

1) Read a file with many rows containing 26 digits in each line 2)Using shell scripting replace 07 with 08 only in 25th and 26th column of each row if 07 is found

Thankyou.

Answer 1

和awk

awk  'BEGIN{FS=""; OFS=""}{if ($25$26 == "07") {$25="0"; $26="8"}{print}}'

Answer 2

如果您确定文件中的每一行都有 26 位数字。（长度 26），您可以：

sed 's/07$/08/' file

Answer 3

这可能对您有用（GNU sed）：

sed -r 's/^(.{24})07/\108/' file