Question

我正在尝试将该awkscript转换为python，而这是我不熟悉的语法。我知道else语句之后的那一部分正在设置用于输出到文件的空格填充，但是if / else使我感到困惑。

if (substr($36,1,1) ~ /^[0-9]+$/) {
   C = $36;
   CLen = length($36);
 } 
 else {
   C = substr($36,2);
   CLen = length(C);
 }
 CPad  = 6 - CLen;
 for (i = 1; i <= CPad; ++i) {
     C = C " "
 }

Answer 1

请参见代码中的#解释。

if (substr($36,1,1) ~ /^[0-9]+$/) {
   # substr($36,1,1) => first char in input field #36
   # ~ => is RegExp match to
   # /^[0-9]+$/ => RegExp of : string consisting of 1 or more digits
   C = $36; # Copy whole input field #36 to variable C
   CLen = length($36); # Assign lenght of input field #36 to variable CLen
 } 
 else { 
   C = substr($36,2); # Copy input field #36 from second char to end, into to variable C
   CLen = length(C); # Assign length of variable C to variable CLen
 }
 CPad  = 6 - CLen; # Compute CPad
 for (i = 1; i <= CPad; ++i) {
     C = C " " # pad CPad spaces to C right side. 
 }

祝你好运。

Answer 2

请注意，这是substr和regex匹配的无用组合

substr($36,1,1) ~ /^[0-9]+$/

相当于$36 ~ /^[0-9]/

也可以用右填充6个字符

c=sprintf("%-6s",c)

总而言之，如果第一个字符为数字，则将其删除，右填充至6个字符长。也许这样更容易...

sub(/^[0-9]/,"",$36); c=sprintf("%-6s",$36)

这一段awk脚本在做什么？

2 个答案: