Javascript Json值不适用于nv.D3累积线图

我正在使用nvd3库处理累积图。下面是一个例子的链接

数据数组是

$temp = array (
    [1409097600000] => 329523
    [1409101200000] => 0
    [1409104800000] => 0
    [1409108400000] => 0
    [1409112000000] => 372369
    [1409115600000] => 494801
    [1409119200000] => 576647
    [1409122800000] => 676672
    [1409126400000] => 672123
    [1409130000000] => 608521
    [1409133600000] => 595265
    [1409137200000] => 516413
    [1409140800000] => 515606
    [1409144400000] => 848533
    [1409148000000] => 670071
    [1409151600000] => 523070
    [1409155200000] => 487250
    [1409158800000] => 532883
    [1409162400000] => 381034
    [1409166000000] => 391296
    [1409169600000] => 308791
    [1409173200000] => 319087
    [1409176800000] => 292183
    [1409180400000] => 237342
)

我想把它当作

在我的例子中，我使用以下php代码生成数据

 foreach ($temp as $timestamp => $value) {
            $result[] = "[" . $timestamp . "," . $value . "]";
 }
$value = "[" . join(",", $result) . "]";

$data[] = array(
                'key' => $slab,
                'value' => $value
            );
return $data

输出为：

[{"key":"2014-08-26","value":"[[1409097600000,329523],[1409101200000,0],[1409104800000,0],[1409108400000,0],[1409112000000,372369],[1409115600000,494801],[1409119200000,576647],[1409122800000,676672],[1409126400000,672123],[1409130000000,608521],[1409133600000,595265],[1409137200000,516413],[1409140800000,515606],[1409144400000,848533],[1409148000000,670071],[1409151600000,523070],[1409155200000,487250],[1409158800000,532883],[1409162400000,381034],[1409166000000,391296],[1409169600000,308791],[1409173200000,319087],[1409176800000,292183],[1409180400000,237342]]"}]

---

据我所知，值是一个字符串，但在示例中它是不同的。是否有人可以帮助我查找错误。

该值不是字符串。删除它周围的引号。另外，它是“值”，而不是“值”