Perl取兩組資料的並集 交集 差集等

2021-09-05 11:54:52 字數 2922 閱讀 3274

目前自己編寫和網上查閱到比較方便的三種方法。

目錄

1. 自寫指令碼，較繁瑣

2. 來自zk1878的指令碼，短小精悍

3. array::utils包，簡便

4. data::dumper包，較簡便

1. **如下：

#! /usr/bin/perl


use warnings;


use strict;


open a, $argv[0] or die;


open b, $argv[1] or die;


open union, '>', "union.txt" or die;


open intsec, '>', "intsec.txt" or die;


open diff, '>', "diff.txt" or die;


open a_spec, '>', "a_spec.txt" or die;


open b_spec, '>', "b_spec.txt" or die;


my @a;


my @b;


while () 


while () 


my @union;#並集 


my @diff; #差集 


my @intsec;#交集 


my @a_spec;


my @b_spec;


my %union;


my %intsec;


my %a;


my %b;


foreach (@a) ++; $a++;}


foreach (@b) ++; $b++;}


@union = keys %union;


foreach (@union) and $union == 1) 


elsif ($union == 1 and $b == 1) 


else 


}@diff = (@a_spec, @b_spec);


print union (join "\n",@union); 


print intsec (join "\n",@intsec); 


print diff (join "\n", @diff); 


print a_spec (join "\n", @a_spec);


print b_spec (join "\n", @b_spec);
2. 參考親測非常好用，**如下：

@a=('a'..'c',1..3);  


@b=('a'..'c',1..3); 


@union=();#並集 


@diff=(); #差集 


@isect=();#交集 


foreach $e(@a,@b)++&&$isect++; 


} @union=keys %union; 


@isect=keys %isect; 


@diff=grep ==1;} @union; 


print (join ',',@union); 


print "\n"; 


print (join ',',@isect); 


print "\n"; 


print (join ',', @diff);
輸出：

a,a,3,b,2,c,1,c,b  


1,3,2 


a,a,b,c,c,b
3. 參考 目測也非常簡便，但沒有試：

use array::utils qw(:all);


my @a = qw( a b c d );


my @b = qw( c d e f );


# symmetric difference


my @diff = array_diff(@a, @b);


# intersection


my @isect = intersect(@a, @b);


# unique union


my @unique = unique(@a, @b);


# check if arrays contain same members


if ( !array_diff(@a, @b) ) 


# get items from array @a that are not in array @b


my @minus = array_minus( @a, @b );
4. 參考沒試，**如下：

#!/usr/bin/perl 


use strict; 


use warnings; 


use data::dumper; 


my @a = (1,2,3,4,5,6,7,8,); 


my @b = (1,9,0,4,15,6,12,8); 


my %hash_a = map @a; 


my %hash_b = map @b; 


my %merge_all = map @a,@b; 


my @a_only = grep } @a; 


my @b_only = grep } @b; 


my @common = grep } @b; 


my @merge = keys (%merge_all); 


print "a only :\n"; 


print dumper(\@a_only); 


print "b only :\n"; 


print dumper(\@b_only); 


print "common :\n"; 


print dumper(\@common); 


print "merge :\n"; 


print dumper(\@merge);

Postgresql取並集，交集，差集

關鍵字union 例子 query1 union query2 關鍵字intersect 例子 query1 intersect query2 關鍵字except 例子 query1 except query2 其中query1和query2的select子句中欄位個數必須相同，且對應的資料型別必須...

C 對List取交集 差集以及並集

list以string型別為例，實際應用中可換做其他型別 1 取交集 取交集 static void intersection listlist2 new list listlist3 new list list3 list1.intersect list2 tolist console.write...

java set 的交集，並集，差集

近日做專案，有個需求是這樣的，有個map1,map2，這兩個map的key有可能是重複的，如果有重複的key，則找出重複的key，然後刪除map1中重複的key以及value，以map2為準，但是map1下面還有用處。然後想到用set求交集不就好了，於是這樣做了 set set1 map1.keys...