马上就要用awk来分析一些日志，所以今天继续恶补。书上的例子看了就懂，有些飘飘然。然而真正动手却发现不是那么回事。看来好记性不如烂笔头，有些东西记下来比较好。
举个最简单的例子吧，用awk求一列的最大值和最小值。按照书中的要求来写出内容。其中最让人恶心的大概就是这个字符串转数字了。
BEGIN { FS= "[:]"; print " ***CAMPAIGN 1998 CONTRIBUTIONS*** /n"; print "---------------------------------------------------------------------------/n"; printf "%-20s/t"s/t%8s/t%8s/t%8s/t%8s/t/n", "NAME", "PHONE", "Jan |", " Feb|", "Mar |", "TotalDonated"; print "---------------------------------------------------------------------------/n"; } { if ( NR == 1 ) { min = $3+ 0; max = $5+ 0; } else { if ( ( $3+ 0 ) < min ) { min = $3+ 0 } if ( ( $5+ 0 ) > max ) { max = $5+ 0 } } $6 = $3+ $4+ $5; total += $6; printf "%-25s/t"s/t%8s/t%6.2f/t%6.2f/t%6.2f/t/n", $1, $2, $3, $4, $5, $6; } END { avg = total /NR; print "--------------------------------------------/n"; print " SUMMARY /n"; printf "The campaign received a total of $%6.2 for this quarter./n",total; printf "The everage donation for the "NR " contribuors was $%6.2f/n",avg; printf "The highest contribution was $%6.2f/n",max; printf "The lowest contribution was $%6.2f/n",min; }如果min = $3+0; max = $5+0;这里不写上这个+0的话，得出的最大值最小值是按字符串方式比较的。(这个我现在也不敢肯定了，不过至少在我的服务器环境下面是这样的，我怀疑和我拷贝过去的原数据文件格式有关，可能在最后一列后面多出空格之类的东西）
现结果如下：
awk_min_max
