javascript中数组里对象怎么去重

Question

 var arr1 = [{x:513.4261838440111,y:174},
                        {x:270.3404255319149,y:174},
                        {x:513.4261838440111,y:174},
                        {x:520.5167237931058,y:369.80798782499784},
                        {x:520.5167237931058,y:369.80798782499784},
                        {x:241.57929926401988,y:381.9650668601638},
                        {x:270.3404255319149,y:174},
                        {x:241.5792992640199,y:381.9650668601638}
                    ]

Answer 1

var kv = [];

$.map(arr1, function (obj) {
if (obj.x != kv[obj.x] && obj.y != kv[obj.y]) {
kv[obj.x] = obj.y;
}
});