Re: [R] loops and if statements

2010-04-18 Thread Erich Neuwirth
I would prefer version 1. Version to creates a global variable R which you do not really need since it contains the same values as d$r. In option 2, you should probably remove the variable r itself after it has been appended to d. On 4/18/2010 5:23 PM, Laura Ferrero-Miliani wrote: > Thanks for co

Re: [R] loops and if statements

2010-04-18 Thread Laura Ferrero-Miliani
Thank you so much all! How a simple problem can get complicated by not having enough knowledge, but hopefully I am learning Have a great Sunday! L On Sun, Apr 18, 2010 at 4:56 PM, jim holtman wrote: > You are working with a matrix, so the "$" operator is not allowed (e.g., > d$c). > > Also in

Re: [R] loops and if statements

2010-04-18 Thread Joshua Wiley
Hey Laura, Just to add a cautionary note, in > a <- c(1:4) > b <- c("meep", "foo", "meep", "foo") > d <- cbind(a, b) d is a matrix and will only be one type of matrix.  Since you have both integer (a) and character (b) data, it has to be at the character level.  From the help for cbind: "The t

Re: [R] loops and if statements

2010-04-18 Thread jim holtman
You are working with a matrix, so the "$" operator is not allowed (e.g., d$c). Also in your test, you have to test against the second column (e.g., d[i, 2]) try this: > a <- c(1:4) > b <- c("meep", "foo", "meep", "foo") > d <- cbind(a, b) > > > for(i in seq(along=d[,2])) {if (d[i,2]=="meep") { p

[R] loops and if statements

2010-04-18 Thread Laura Ferrero-Miliani
Hello, I am very new to R and data analysis in general. I am trying to generate values to append to my data frame using conditional statements. I am playing with this simple example: a <- c(1:4) b <- c("meep", "foo", "meep", "foo") d <- cbind(a, b) now what I want to do is , each time there is a