search for: rushworth

I'd like to pass a list object created by one function as an argument of another function. once inside the second function, I'd like to break the list up to it's individual elements, each then identifiable by the 'names' of the list. The list looks something like lst<-list(a=1, b=2, df=5, g=7) then inside the function I've been writing a sequence of statements that

I'm trying to calculate the row-wise kronecker product A \Box B of two sparse matrices A and B, and am struggling to find a quick way to do this that takes advantage of sparseness. I thought a good idea would be to use "rep" to construct 2 matrices of the same dimension of the end product, and multiply these two together: library(Matrix) A<-Matrix(c(1,0,0,0,0,1,2,0), 2, 4)

I have a complex 2D polygon with thousands of vertices, and I'd like to be able to identify points from a large set contained within the polygon, and was wondering if there might be an efficient way of doing this? Any advice would be useful! Here is a small example of what I mean: # make polygon v1<-c(0,1,1,2,1,3,6,7) v2<-c(1,3,3,5,6,7,8,9) plot(v1, v2, type = "n" )

Hi, I'm trying to use grid.polygon() to plot several polygons at once, with a view to putting coloured polygons beneath a curve. I'm struggling just to get the grid.polygon to plot anything # PLOT SOME POINTS x <- 1:100 y <- 1:100*0.5 + 3 plot(x, y, pch = ".") # PLOT 2 POLYGONS library(grid) grid.polygon(x = c(20, 20, 40, 40, 40, 40, 60, 60), y =

Hello, Does anyone know how the parameter estimates are calculated for xreg variables when called as part of an arima() command, or know of any literature that provides this info? In particular, I was wondering if there is a quick way to compare different combinations of "xreg" variables in the arima() fit in the same way that you would in multiple regression (using AIC & R^2

Dear R-Help, I have a data frame and a vector df=data.frame(Letter=c("Z","Q","R","A","E","F"), Number=c(11,32,4,1,9,3)) v=c("C","Q","R","A","E") >From df, I'd like to construct a subset of the field "Number", with deletions dictated by the vector, v, of letters.