How to average within bins? Indexing again...

I am trying to average data corresponding to bins. Here is a simplified example (attached). I have real distances in the first column, and then real durations. I have binned the distances and added them to the array (with the help of Matlab Central users). Now what I want to do is extract the durations that match a given bin (say, 0), and then average them. Each bin will then be associated, in a different array, with its average duration.

Here's what I have so far, but I don't want to have to rewrite all of these statements for each bin. I have >35 bins! I'm not good with indexing but sometimes it seems there are easier ways to do things than with indexing, so hopefully that is the case here.

=======================

%%%%%%%%%%starting array

dist=[2 4 6 9];

duration=[3 4 10 11];

bin=[0 0 5 5];

data=[dist' duration' bin']

%%%%%%%%%%extracts durations only where bin=some number

bin0=logical(data(:,3)==0);

bin0dur=(data(:,2).*bin0);

bin5=logical(data(:,3)==5);

bin5dur=(data(:,2).*bin5);

%%%%%%%%%%removes zeros

bin0dur(bin0dur==0)=[];

bin5dur(bin5dur==0)=[];

%%%%%%%%%%takes mean of remaining durations

meandur0=mean(bin0dur);

meandur5=mean(bin5dur);

%%%%%%%%%%puts mean durations with their bins

bins=[0 5];

durs=[meandur0 meandur5];

datafinal=[bins' durs']

Answer 1

[Jos (10584)]

Using ACCUMARRAY to average the values belonging to the same bin:

dist     = [2 4 6 9] ;
duration = [3 4 10 11];
bin      = [0 0 5 5] ; % how did you get those?

[BinValue,~,ix] = unique(bin) ;
AvgDuration = accumarray(ix,duration,@mean) ;
Result = [BinValue AvgDuration]

Extra: You can use histc to bin the distances

DistEdges = [0 5 10] 
[n, bin] = histc(dist, DistEdges)

Answer 2

[per isakson]

I think it is accumarray, Construct array with accumulation you are looking for. The online help includes some examples.

[B.M.]

Unfortunately the vector I want to pull data from (the subs argument in accumarray) is not made up of integers :(

[per isakson]

Wouldn't it be feasible to create subs?

[B.M.]

I don't know what you mean--but ended up taking a different approach since I needed to pull out data for multiple conditions. Thanks for your suggestion!