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POUsing a string to refer to a structure array - matlab
 

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  1. POUsing a string to refer to a structure array - matlab
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    <p>I am trying to take the averages of a pretty large set of data, so i have created a function to do exactly that. The data is stored in some <code>struct1.struct2.data(:,column)</code> there are 4 <code>struct1</code> and each of these have between 20 and 30 sub-<code>struct2</code> the data that I want to average is always stored in column 7 and I want to output the average of each <code>struct2.data(:,column)</code> into a <code>2xN</code> array/double (column 1 of this output is a reference to each sub-<code>struct2</code> column 2 is the average) </p> <p>The omly problem is, I can't find a way (lots and lots of reading) to point at each structure properly. I am using a string to refer to the structures, but I get error <code>Attempt to reference field of non-structure array.</code> So clearly it doesn't like this. Here is what I used. (excuse the inelegence)</p> <pre><code>function [avrg] = Takemean(prefix,numslits) % place holder arrays avs = []; slits = []; % iterate over the sub-struct (struct2) for currslit=1:numslits dataname = sprintf('%s_slit_%02d',prefix,currslit); % slap the average and slit ID on the end avs(end+1) = mean(prefix.dataname.data(:,7)); slits(end+1) = currslit; end % transpose the arrays avs = avs'; slits = slits'; avrg = cat(2,slits,avs); % slap them together </code></pre> <p>It falls over at this line <code>avs(end+1) = mean(prefix.dataname.data,7);</code> because as you can see, <code>prefix</code> and <code>dataname</code> are strings. So, after hunting around I tried making these strings variables with <code>genvarname()</code> still no luck!</p> <p>I have spent hours on what should have been 5min of coding. :'(</p> <p>Edit: Oh <code>prefix</code> is a string e.g. <code>'Hs'</code> and the structure of the structures (lol) is e.g. <code>Hs.Hs_slit_XX.data()</code> where <code>XX</code> is e.g. <code>01,02,...27</code></p> <p>Edit: If I just run <code>mean(Hs.Hs_slit_01.data(:,7))</code> it works fine... but then I cant iterate over all of the <code>_slit_XX</code></p>
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    1. COWhen you say "there are 4 `struct1` and each of these have between 20 and 30 sub-`struct2`", are you talking about arrays of structures, or separate fields with different names?
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    2. COI am not sure. Basically going by the added example `Hs` is a 1x1 struct but contains `Hs_slit_XX` - each `Hs_slit_XX` contains a 23x8 double called data and 23x6 cell called text data
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    3. COWhy would you pass the name of the structure instead of the structure itself in the first place?
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