强悍的awk

之前同事用perl写了个脚本来分析 数据

数据格式如下，文件有数百M

zhangsan 80

lisi 81.5

wangwu 93

zhangsan 85

lisi 88

wangwu 97

zhangsan 90

lisi 92

wangwu 88

计算每人的平均分和总分

cat test.pl

#!/usr/bin/perl -w

use strict;

BEGIN {

eval{ require List::Util; };

import List::Util qw/sum/ unless $@;

}

my %name;

open my $file,'<','score2.txt' or die "$!\n";

while ( <$file> ) {

chomp;

my @array = split /\s+/;

$name{$array[0]} = [] unless exists $name{$array[0]};

push @{$name{$array[0]}},$array[1];

}

close $file;

print "name#######average#######total\n";

for my $name ( sort keys %name ) {

my @tmp_array = @{$name{$name}};

print $name,"\t",sum(@tmp_array)/(scalar @tmp_array),"\t",sum(@tmp_array),"\n";

}

接着是perl的完成需要的时间

name#######average#######total

lisi 87.1666666666667 201101083.5

wangwu 92.6666666666667 213790062

zhangsan 85 196102395

real 0m16.099s

user 0m15.379s

sys 0m0.713s

我写了awk 的完成时间

time awk ' BEGIN{printf "name\t\t avgscore\t\t\t sum \n"}name[$1]+=$2{};++num[$1]{};END{for( i in name) printf "%s\t\t|%-10f|\t\t|%.2f|\n", i,name[i]/num[i],name[i]}' score2.txt

name avgscore sum

zhangsan |85.000000 | |196102395.00|

lisi |87.166667 | |201101083.50|

wangwu |92.666667 | |213790062.00|

real 0m4.468s

user 0m4.402s

sys 0m0.063s

很给力的awk吧！