按日期分组并减少数组以创建新数组

I have this array:

我有这个数组:

> source

# =>
[[Fri, 13 Mar 2015, [24.2]],
 [Tue, 17 Mar 2015, [0.01, 8.26]],
 [Mon, 16 Mar 2015, [0.01, 0.01, 0.01, 0.01]],
 [Mon, 16 Mar 2015, [0.01, 0.01]],
 [Fri, 13 Mar 2015, [24.2, 24.2, 24.2, 24.2, 24.2, 24.2, 24.2]],
 [Fri, 13 Mar 2015, [24.2, 24.2, 24.2, 24.2, 24.2, 24.2, 24.2, 24.2, 24.2, 24.2]],
 [Mon, 16 Mar 2015, [15.95]],
 [Thu, 12 Mar 2015, [352429.0, 35242900.0, 3.0]]
]
> source

# =>
[