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st: Matrix question
From
[email protected] (Brendan Halpin)
To
[email protected]
Subject
st: Matrix question
Date
Sun, 05 Feb 2012 22:01:56 +0000
I have a large mata matrix that I want to reduce: I want to replace each
block of five rows with a single row containing their mean.
My brute force approach goes as follows
| mata:
| t = mean(s[1..5 , ])
| for (i=2; i<=rows(s)/5; i++) {
| t = t \ mean(s[1+(i-1)*5..5+(i-1)*5 , ])
| }
| end
This works, but am I missing a more efficient way of doing this, some
Mata or matrix-algebra trick?
Something tells me that I should be able to avoid looping here.
Brendan
--
Brendan Halpin, Department of Sociology, University of Limerick, Ireland
Tel: w +353-61-213147 f +353-61-202569 h +353-61-338562; Room F1-009 x 3147
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http://teaching.sociology.ul.ie/bhalpin/wordpress twitter:@ULSociology
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