Re: [R] Help needed for efficient way to loop through rows and columns

ple[i, 5] == "B") { samplemod[i,j] <- switch(sample[i,j], AA = 0, AB = 1, BA = 1, BB = 2) } } } } } -- David L Carlson Associate Professor of Anthropology Texas A&M University College Station, TX 77843-4

Re: [R] Help needed for efficient way to loop through rows and columns

g of all the values in the row. You seem to be coding as if i was > a > single integer (as in a for loop). > > -- > David L Carlson > Associate Professor of Anthropology > Texas A&M University > College Station, TX 778

Re: [R] Help needed for efficient way to loop through rows and columns

Hello, Your data.frame is composed exclusively of factors, but try this (I've changed the name to 'sampl', because 'sample' is an R function.) # logical index vectors iA <- sampl$AorB == "A" iB <- sampl$AorB == "B" new.sampl <- data.frame( apply(sampl, 2, function(x){ i

Re: [R] Help needed for efficient way to loop through rows and columns

May 16, 2012 3:08 AM > To: r-help@r-project.org > Subject: [R] Help needed for efficient way to loop through rows and > columns > > Dear R-helpers: > > I am trying to write a script that iterates through a dataframe that > looks > like this: > > > Example datas

[R] Help needed for efficient way to loop through rows and columns

Dear R-helpers: I am trying to write a script that iterates through a dataframe that looks like this: Example dataset called "sample": names <- c("S1", "S2", "S3", "S4") X <- c("BB", "AB", "AB", "AA") Y <- c("BB", "BB", "AB", "AA") Z <- c("BB", "BB", "AB", NA) AorB <- c("A", "A", "A", "B") sam