Re: how to sum lists of unequal length?
- To: mathgroup at smc.vnet.net
- Subject: [mg70384] Re: how to sum lists of unequal length?
- From: wwwuuu at gmail.com
- Date: Sun, 15 Oct 2006 00:18:47 -0400 (EDT)
- References: <egq2th$84h$1@smc.vnet.net>
zeroFillingMapThread[ h_, args_List] :=
MapThread[ h,
PadRight[#, Max[Length /@ args]] & /@ args]
zeroFillingMapThread[Plus, {{a1, a2, a3}, {b1, b2, b3, b4, b5}}]
=>
{a1 + b1, a2 + b2, a3 + b3, b4, b5}
Arkadiusz.Majka at gmail.com wrote:
> Hi all,
>
> I have lists of unknown and unequal lengths. I want to sum them, e.g
>
> {a1,a2,a3}+{b1,b2,b3,b4,b5} and obtain result
> {a1+b1,a2+b2,a3+b3,b4,b5}. Simply filling by zeros of the shorter list
> is impossible because I have no idea how many zeros I have to pad.
>
> Please, help
>
> Arek