Re: averaging sublists of different lengths
- To: mathgroup at smc.vnet.net
- Subject: [mg75497] Re: averaging sublists of different lengths
- From: "Rolf.Mertig at gmail.com" <Rolf.Mertig at gmail.com>
- Date: Thu, 3 May 2007 03:44:33 -0400 (EDT)
- References: <f19fql$4q7$1@smc.vnet.net>
Hi,
one possibility is:
Mathematica 6.0 for Linux x86 (64-bit)
Copyright 1988-2007 Wolfram Research, Inc.
In[1]:= FilePrint@"m.m"
MyMean[mat:{{__?NumberQ}..}]:=Module[{max,tmat},
max=Max[Length/@mat];
tmat=Transpose[PadRight[#,max,Hold[Sequence[]]]&/@mat];
Mean/@ReleaseHold[tmat]];
InputForm @ MyMean[
{{70,66,64,68,64,56,68,78,62,68,84},{70,64,64,56,66,
56,62,
64,66,88,54,72},{58,54,54,60,72,70,62,68,74,76,70},
{66,
56,60,64,56,62,68,58,58,58,68,76,62,76,66,64,88,
56},{56,
64,72,72,70,62,76,76,76,76,86,80,100},{60,60,70,68,
60,60,
50,56,60,70,62,68,88,84,82},{54,66,72,62,70,66,
70,
56},{60,60,60,62,74,80,70},{54,62,64,72,76,74},{66,
74,70,
80,54,54,64},{72,66,60,52,52,66,66,58,60,66}}
]
In[2]:= <<m.m
Out[2]//InputForm=
{686/11, 692/11, 710/11, 716/11, 714/11, 706/11, 328/5, 257/4, 456/7,
502/7,
212/3, 74, 250/3, 80, 74, 64, 88, 56}
Regards,
Rolf Mertig
GluonVision GmbH
http://www.gluonvision.com
On 2 Mai, 09:49, dantimatter <dantimat... at gmail.com> wrote:
> Hello all,
>
> I have a list of lists like this:
>
> {{70, 66, 64, 68, 64, 56, 68, 78, 62, 68, 84}, {70, 64, 64, 56, 66,
> 56, 62,
> 64, 66, 88, 54, 72}, {58, 54, 54, 60, 72, 70, 62, 68, 74, 76, 70},
> {66,
> 56, 60, 64, 56, 62, 68, 58, 58, 58, 68, 76, 62, 76, 66, 64, 88,
> 56}, {56,
> 64, 72, 72, 70, 62, 76, 76, 76, 76, 86, 80, 100}, {60, 60, 70, 68,
> 60, 60,
> 50, 56, 60, 70, 62, 68, 88, 84, 82}, {54, 66, 72, 62, 70, 66,
> 70,
> 56}, {60, 60, 60, 62, 74, 80, 70}, {54, 62, 64, 72, 76, 74}, {66,
> 74, 70,
> 80, 54, 54, 64}, {72, 66, 60, 52, 52, 66, 66, 58, 60, 66}}
>
> What I'd really like is the average all the 1st values, 2nd values,
> etc, but I'm having trouble figuring out how to deal with the fact
> that the lists are not all the same length. Is there a way to drop
> the sublists as they run out of points to add to the average, i.e. if
> I want the average of all the nth values, but Length[shortSublist] <
> n, can I somehow drop shortSublist and then calculate the average from
> the other sublists?
>
> Also, the Mean[] function requires more than one data point, but I'd
> still like to extract out the values for which there is only one data
> point. Is there a way to do this?
>
> Thanks!
> dan