how to add a moving average filter

    I have a data that is orgnized in the following way:
  In the first column I have years from 1950 - 2011.  In the 2nd column I have months ranging from 1 - 12.  In the 3rd column i have and index which is a assocated with a number.  
  Example of data:
  1950 1 0.73
  1950 2 0.44
  and so forth.
I have the following code to plot ithe data annually. 

clear all
        clear all
        tfile2='cpc_monthly_nao.ascii';
        fid2=fopen(tfile2,'r');
        [year_m,month,index_month]=textread(tfile2,'%d %d %f');
        ind=1;
        m=size(index_month);
        for ii=1:12:m
            year(ind)=year_m(ii);
%       DJFM
         if ii > 1
            index(ind)=(index_month(ii-1)+index_month(ii)+index_month(ii+1)+index_month(ii+2)+index_month(ii+3)+index_month(ii+4)+index_month(ii+5)+index_month(ii+6)+index_month(ii+7)+index_month(ii+8)+index_month(ii+9)+index_month(ii+10)+index_month(ii+11))/12.0;
            ind=ind+1;
         end
        end
        hold on
        bar(year,index,'k')
        plot(year,0.0,'b')
        [y,i]=sort(index);
        year(i)
        [y2,i2]=sort(abs(index));
        year(i2)

The above code plots the data annually. I now want to plot the data annually with a 3 month moving average filter. How do I do that?

Answer 1

[Andrew Newell]

See filter.

[Raquel]

when i clicked the above link "filter" it said "page not found"

[Andrew Newell]

Sorry - I didn't copy the address correctly. It works now.