Also, see ?aggregate: > with(A, aggregate(no_of_accidents, by=list(SEX=sex), FUN='sum')) SEX x 1 F 34 2 M 83
> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Attiglah, Mama > Sent: Tuesday, January 29, 2008 7:21 AM > To: [EMAIL PROTECTED]; r-help@r-project.org > Subject: Re: [R] pivot table in R > > A = read.table("clipboard", header=TRUE) > > A > sex age region no_of_accidents > 1 F young north 10 > 2 F young south 12 > 3 F old north 5 > 4 F old south 7 > 5 M young north 24 > 6 M young south 30 > 7 M old north 12 > 8 M old south 17 > > > > > > sum(A$no_of_accidents[which( A$sex=="F")]) > > should give you the required sum. > > You have to remember that sex, age and region are Factors > with their respective levels and no_of_accidents is a numeric vector. > > Do str( A) to see their type. > Hope that helps. > > Mama > > ----- > Mama Attiglah, PhD > Advanced Research Center > Quantitative Research Analyst > State Street Bank > +44(0)20 7698 6290 (Direct Line) > +44 (0)207 004 2968 (Direct Fax) > Please visit our Web site at > www.ssga.com > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > On Behalf Of [EMAIL PROTECTED] > Sent: 29 January 2008 12:05 > To: r-help@r-project.org > Subject: [R] pivot table in R > > Hello, > > I'm struggling with an elementary problem with R. I have a > simple data frame such as this one giving the number of > accidents subdivided by sex, > > age and region. > > sex age region no_of_accidents > > F young north 10 > F young south 12 > F old north 5 > F old south 7 > M young north 24 > M young south 30 > M old north 12 > M old south 17 > > and I would like to build a pivot table, e.g. obtaining the > sum of the number of accidents for each sex: > > sex age region no_of_accidents > > F (any) (any) 34 > M (any) (any) 83 > > but I can't seem to obtain this result simply in R, except by > embarking in complicated "for" loops. > > I have checked the documentation on such functions as > "table()" and the documentation on "An introduction to R" but > couldn't solve the problem. > Could you please help me with this? > > Cheers > > Pete > > > PLEASE CONSIDER THE ENVIRONMENT BEFORE PRINTING THIS E-MAIL > > For Aon's standard conditions associated with this e-mail > please visit http://www.aon.com/uk/en/email-footer/aon-limited.jsp > Aon Limited > Registered Office: 8 Devonshire Square, London EC2M 4PL > Registered in London No. 210725 . VAT Registration No. 480 8401 48 > > Aon Limited is authorised and regulated by the Financial > Services Authority in respect of insurance mediation activities only. > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
