[R] How to reformat data from database into data.frame?

[Gabor Grothendieck]

Assuming your input data frame is genes:

  reshape(genes,idvar="GeneID",timevar="MethodID",direction="wide")


 --- On Wed 10/22, Mark Dalphin < mdalphin at amgen.com > wrote:
From: Mark Dalphin [mailto: mdalphin at amgen.com]
To: r-help at stat.math.ethz.ch
Date: Wed, 22 Oct 2003 12:05:44 -0700
Subject: [R] How to reformat data from database into data.frame?

I'm trying to find a clever way to re-map data from a database<br>query into a data.frame.<br><br>Querying a database often returns a table (data.frame) like this:<br><br>GeneID	 MethodID   Value<br>6	 1	    123<br>6	 2	    456<br>6	 3	    987<br>7	 1	    234<br>7	 3	    432<br>8	 2	    190<br>8	 3	    34<br>8	 1	    864	    <br><br>Note that GeneID=7 doesn't have a value for MethodID=2.<br><br>Note that GeneID=8 doesn't have the MethodID in any particular order<br>and, in fact, there doesn't need to be an order to the GeneID, although<br>I can force ordering as part of my SQL query.<br><br>I want to reformat this into a data.frame with multiple columns:<br><br>       Value	   Value     Value<br>GeneID Method1	   Method2   Method3<br>6      123	   456	     987<br>7      234	   NA	     432<br>8      864	   190	     34<br><br>Is there an elegant way to do this type of reformating in R?<br><br>Thanks.<br>Mark<br><br>-- <br>Mark Dalphin                          email: mdalphin at amgen.com<br>Mail Stop: 29-2-A                     phone: +1-805-447-4951 (work)<br>One Amgen Center Drive                       +1-805-375-0680 (home)<br>Thousand Oaks, CA 91320                 fax: +1-805-499-9955 (work)<br><br>______________________________________________<br>R-help at stat.math.ethz.ch mailing list<br>https://www.stat.math.ethz.ch/mailman/listinfo/r-help<br>

_______________________________________________
No banners. No pop-ups. No kidding.
Introducing My Way - http://www.myway.com