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using acummarray to average several columns at a time?

 Hello

 
I have a data array (mat) with the following dimensions: 149016x93
The columns are
year | month | day | hour | data 1 | data 2 | data 3 | and so on until data 89
2001 | 1 | 1 | 0 | random numbers ...
... | ... | ... | ... | random numbers ...
2017 | 12 | 31 | 23 | random numbers ...
 
The data is random and it is what I want to average.
I found this example (MathWorks example) and it is fine, however I've been strugling in how to run it over column 5 to 93...
 
[ah,~,ch] = unique(mat(:,2:4),'rows');
hraverage = [ah,accumarray(ch,mat(:,5),[],@nanmean)];
y problem is that I'm not being able to have as an output the 8784x93 array, only an 8784* x 4, I've tried loops but i'm missing something that I am not aware of...
 
*The dataset has several years of data. I want the hour average for each each day of the year. So it's 366 days * 24hours = 8784
 
for the sake of example, please feel free to consider a smaller array.
 
thank you for the attention! will keep digging on this...
 
sample data in attachment. randomly generated:
 
4 first collumns are: year, month, day, hour, and columns 5 to 7 are data columns.
 
the final result should be a 8784x7 file.


NOTE:-


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There's a simpler way of doing this with groupsummary
I imported the sampledata and made the table with 7 columns:
 
Year,Month,Day,Hour,VarName5,VarName6,VarName7
 
Then used the following commands to take advantage of binning in groupsummary and of being able to include empty groups:
 
 
sampledata.Time = datetime(sampledata.Year,sampledata.Month,sampledata.Day)
result = groupsummary(sampledata,{'Time','Hour'},{'dayofyear','none'},'mean',{'VarName5','VarName6','VarName7'},'IncludeEmptyGroups',1)

 

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