search for: looplessly

when subsetting a matrix results in a single row, it is converted to a vector, not a matrix. how do I avoid this? 1. __GOOD__ > edges <- get.edges(g,E(g)) > edges [,1] [,2] [1,] 0 2 [2,] 0 3 [3,] 0 4 [4,] 0 5 [5,] 1 1 [6,] 0 4 [7,] 0 6 [8,] 0 7 [9,] 0 8 [10,] 0 9 [11,] 0 5 [12,] 0 10 [13,] 0 11

Hi, I have a good grasp of grep() and gsub() for finding and extracting character strings. However, I cannot figure out how to use a search term that is stored in a variable when the search string is more complex. #Say I have a string, and want to know whether the last name "Jannings" is in the string. This is done by names=c("Emil Jannings") grep("Emil",names)

Hi there, I have two questions on matrix manipulation. For the first one, I want to calculate the product of each column of a matrix (say A) with another vector (say b). That is, if A has 5 columns (a1, a2, a3, a4, a5), I want to obtain a matrix with columns (a1*b, a2*b, aA3*b, a4*b, a5*b). Can I do it directly, without using "for" loop? For the second one, I have a matrix A of

Sorry about the odd terminology, but I suspect that my intent might be completely missed had I used "aggregate" or "classify" (each of which appears to have some rather special meanings in statistical analysis and modeling). I have some data about software builds; one of the characteristics of each is the name of the branch. A colleague has generated some fairly interesting

Dear list, this must be an easy one: I have a data.frame of two columns, "ID" with four different levels (A to D) and numerical "size", and each of the 4 different IDs is repeated a different number of times. I would like to get the mean size for each ID as another data.frame. I have tried the following: >ID= as.character(unique(data[,1])) # I use unique() because