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Topic: filling a matrix
Replies: 2   Last Post: Nov 21, 2012 12:09 PM

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 Jonathan Allan Posts: 123 Registered: 12/7/04
Re: filling a matrix
Posted: Nov 21, 2012 12:09 PM

"Roger Stafford" wrote in message <k8hgok\$qm2\$1@newscl01ah.mathworks.com>...
> "Jonathan " <jkakiwi@yahoo.co.uk> wrote in message <k8hba8\$9co\$1@newscl01ah.mathworks.com>...
> > G'day,
> > I'm trying to read in hourly data from multiple years and create a matrix that incrementally adds each year of data to the same matrix. The code I have is:
> >
> > j1 = [1975,1977,1978,1979,1981,1982,1983,1985,1986,1987,...
> > 1989,1990,1991,1993,1994,1995,1997,1998,1999,2001,2002,2003,...
> > 2005,2006,2007,2009,2010,2011]; %normal years
> > j2 = [1928,1932,1936,1940,1944,1948,1952,1956,1960,1964,1968,1972,...
> > 1976,1980,1984,1988,1992,1996,2000,2004,2008,2012]; %leap years
> >
> > tst=1987:1989;
> > N=length(tst);
> > A = NaN*ones(N,8784); %fill with NaNs
> >
> > for m=1987:1989; % add hourly data
> > for j=1:N;
> > fname=sprintf('yaq%d.txt',m);
> > if any(m == j1);
> > Hs=data(:,5);
> > A(j,1:length(Hs)) = Hs;
> > elseif any(m == j2);
> > Hs=data(:,5);
> > A(j,1:length(Hs)) = Hs;
> > end
> > end
> > end
> >
> > However, my code seems to be only repeating the last year of data. I know its a simple fix but I'm having a mind block. What am I doing wrong?
> >
> > Thanks.

> - - - - - - - - -
> I see (at least) two problems here. First you have one too many for-loops. You ought to do something like this:
>
> A = NaN*ones(N,8784); %fill with NaNs
> tst=1987:1989;
> for j = 1:length(tst)
> m = tst(j); % <-- Use this method of varying m, not a second nested loop
> fname=sprintf('yaq%d.txt',m);
> (Now store 'fname' data in A)
> end
>
> The second problem is that your choice between "normal years" and "leap years" is not affecting any result in A here. Both parts of the if-elseif-end choice do exactly the same thing. You presumably had something other than this in mind here.
>
> Roger Stafford

Thanks Roger, this worked.

Date Subject Author
11/20/12 Jonathan Allan
11/20/12 Roger Stafford
11/21/12 Jonathan Allan