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From |
brendan.halpin@ul.ie (Brendan Halpin) |

To |
statalist@hsphsun2.harvard.edu |

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 mailto:brendan.halpin@ul.ie ULSociology on Facebook: http://on.fb.me/fjIK9t http://teaching.sociology.ul.ie/bhalpin/wordpress twitter:@ULSociology * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

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