Creates an intersection of sorted sets given in second argument. The result of the union will be stored in the sorted set defined by the first argument. The third optionnel argument defines weights to apply to the sorted sets in input. In this case, the weights will be multiplied by the score of each element in the sorted set before applying the aggregation. The forth argument defines the AGGREGATEoption which specify how the results of the union are aggregated.
计算numkeys个由keys指定的有序集合的交集，并且将结果存储在destination中。在该命令中，在你传递输入keys之前，必须提供输入keys的个数和其它可选的参数。
在默认情况下，一个元素的结果score是具有该元素的所有有序集合的score的和。关于WEIGHTS和AGGREGATE选项，可以参看ZUNIONSTORE命令。如果目标已经存在，那么它将会被重写。
Parameters
keyOutput
arrayZSetKeys
arrayWeights
aggregateFunction Either "SUM", "MIN", or "MAX": defines the behaviour to use on duplicate entries during the zInter.
Return value
LONG The number of values in the new sorted set.
Example
$redis->delete('k1');
$redis->delete('k2');
$redis->delete('k3');
$redis->delete('ko1');
$redis->delete('ko2');
$redis->delete('ko3');
$redis->delete('ko4');
$redis->zAdd('k1', 0, 'val0');
$redis->zAdd('k1', 1, 'val1');
$redis->zAdd('k1', 3, 'val3');
$redis->zAdd('k2', 2, 'val1');
$redis->zAdd('k2', 3, 'val3');
$redis->zInter('ko1', array('k1', 'k2')); /* 2, 'ko1' => array('val1', 'val3') */
$redis->zInter('ko2', array('k1', 'k2'), array(1, 1)); /* 2, 'ko2' => array('val1', 'val3') */
/* Weighted zInter */
$redis->zInter('ko3', array('k1', 'k2'), array(1, 5), 'min'); /* 2, 'ko3' => array('val1', 'val3') */
$redis->zInter('ko4', array('k1', 'k2'), array(1, 5), 'max'); /* 2, 'ko4' => array('val3', 'val1') */
