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...as.factor(as.numeric(cut(r,c(0,2,4,6,8,10,100)))) > levels(col_no) <- c("<2%","2-4%","4-6%","6-8%","8-10%",">10%") > col_no [1] <2%? <2%? 2-4% <2%? <2%? <2% Levels: <2% 2-4% 4-6% 6-8% 8-10% >10%Thanks, Tianchan

Dear All, I was using rk4 and lsoda to solve a ODE system. However, both of them gave bad accurate solutions, especially compared with Matlab solver ODE45. For example, ODE45 gave solutions that can go to a stable level (about 1.6) when time goes to infinity, however, the solutions from lsoda are decreasing to very very small (about 1e-130) numbers. Does R have more accurate ODE solvers as

Dear All, I am trying to use ode solver "rk4" to solve an ODE system, however, it keeps saying: Error in eval(expr, envir, enclos) : object "dIN" not found. The sample codes are enclosed as follows, please help me. Thank you very much! rm(list=ls()) library(odesolve) # The ODE system ode <- function(t,x,p){ with(as.list(c(x,p)),{

Dear All, I am trying to use ode solver "rk4" to solve an ODE system, however, it keeps saying: Error in eval(expr, envir, enclos) : object "dIN" not found. The sample codes are enclosed as follows, please help me. Thank you very much! rm(list=ls()) library(odesolve) # The ODE system ode <- function(t,x,p){ with(as.list(c(x,p)),{

Try this: y <- rnorm(100) X <- matrix(runif(100 * 10), ncol = 10) lm(y ~ ., data = cbind.data.frame(y, X)) On Tue, Nov 16, 2010 at 5:07 PM, Tianchan Niu <niu@isis.georgetown.edu>wrote: > Dear All,I would like to do multiple regression in R. I used: lm(y~X), > where y is a n by 1 vector, and X is a n by m matrix. I kept getting the > error > message:Error in model.frame.default(formula = y ~ X, : invalid type > (list) for...