$arr = array( array( 'imp' => 1000, 'clk' => 100, 'date' => 20150601 ), array( 'imp' => 1002, 'clk' => 102, 'date' => 20150602 ), array( 'imp' => 1003, 'clk' => 103, 'date' => 20150601 ));

求这个数组里相同日期的曝光总和、点击总和，用最简洁的代码表示出来
imp 曝光
clk 点击
date 日期
回复内容： $arr = array( array( 'imp' => 1000, 'clk' => 100, 'date' => 20150601 ), array( 'imp' => 1002, 'clk' => 102, 'date' => 20150602 ), array( 'imp' => 1003, 'clk' => 103, 'date' => 20150601 ));

求这个数组里相同日期的曝光总和、点击总和，用最简洁的代码表示出来
imp 曝光
clk 点击
date 日期
php$a=array();foreach($arr as $v){ $a[$v['date']]['clk']+=$v['clk']; $a[$v['date']]['imp']+=$v['imp'];}print_r($a);
php$res=[];foreach ($arr as $key => $value) { $res[$value['date']] =array( 'imp' =>isset($res[$value['date']]) ? $res[$value['date']]['imp']+$value['imp'] : $value['imp'], 'clk' =>isset($res[$value['date']]) ? $res[$value['date']]['clk']+$value['clk'] : $value['clk'], 'date' =>$value['date'] );}print_r(array_values($res));array( [0] => array ( [imp] => 2003 [clk] => 203 [date] => 20150601 ) [1] => array ( [imp] => 1002 [clk] => 102 [date] => 20150602 ))
$tmp = array();foreach($arr as $k => $v) { $tmp[$k] = $v['date'];}$tmp = array_unique($tmp);/* 去重后得array( [0] => 20150601 [1] => 20150602)*/$tmp2 = array();foreach($tmp as $k => $v) { $tmp2[$v]['imp'] = 0; $tmp2[$v]['clk'] = 0;}/* 初始化得array( [20150601] => array ( [imp] => 0 [clk] => 0 ) [20150602] => array ( [imp] => 0 [clk] => 0 ))*/foreach($tmp as $k => $v) { foreach($arr as $k2 => $v2) { if($v == $v2['date']) { $tmp2[$v]['imp'] += $v2['imp']; $tmp2[$v]['clk'] += $v2['clk']; } }}print_r($tmp2);/* 求和得array( [20150601] => array ( [imp] => 2003 [clk] => 203 ) [20150602] => array ( [imp] => 1002 [clk] => 102 ))*/
来个reduce版本
1000, 'clk' => 100, 'date' => 20150601 ), array( 'imp' => 1002, 'clk' => 102, 'date' => 20150602 ), array( 'imp' => 1003, 'clk' => 103, 'date' => 20150601 ));$result = array_reduce($arr, function($left, $right) { if(isset($right['imp'])) $left['imp'] += $right['imp']; if(isset($right['clk'])) $left['clk'] += $right['clk']; return $left;}, [ 'imp' => 0, 'clk' => 0]);print_r($result);
http://3v4l.org/58v94
专业问题。。学习了