awk统计

[guodongxiaren]

求和

cat data|awk '{sum+=$1} END {print "Sum = ", sum}'

求平均

cat data|awk '{sum+=$1} END {print "Average = ", sum/NR}'

求最大值

cat data|awk 'BEGIN {max = 0} {if ($1>max) max=$1 } END {print "Max=", max}'

求最小值（min的初始值设置一个超大数即可）

awk 'BEGIN {min = 1999999} {if ($1<min) min=$1} END {print "Min=", min}'

百分位值

降文件b的低5列，求50分位、60分位、80分位、90分位、99分位的值

sort -nk5 b|awk '{all[NR] = $5} END{print all[int(NR*0.5-0.5)] "\t" all[int(NR*0.6-0.5)] "\t"all[int(NR*0.8-0.5)] "\t"all[int(NR*0.9-0.5)] "\t"all[int(NR*0.959-0.5)]}' 

减去0.5是为了向下去整