如何定义与赋值这样的JS多维数组？

Question

[['Firefox',   44.2],['IE7',26.6],['Chrome',    3.1],['Safari',    2.7],['Opera',     2.3],['Mozilla',0.4]]  这样子的数组如何定义 与 赋值？

Answer 1

var a = []
a[0] = ['Firefox', 44.2]
a[1] = ['IE7',26.6]

Answer 2

<script>
var arr = [['Firefox', 44.2],['IE7',26.6],['Chrome', 3.1],['Safari', 2.7],['Opera', 2.3],['Mozilla',0.4]];
alert(arr[0][0]);//Firefox
alert(arr[1][1]);//26.6
</script>

Answer 3

var arry = new Array();
arry['Firefox'] = ['44.2'];
arry['IE7'] = ['26.6'];
arry['Chrome'] = ['3.1'];
arry['Safari'] = ['2.7'];
arry['Opera'] = ['2.3'];
arry['Mozilla'] = ['0.4'];用到数时用parseFloat();转换一下