similar to: break an axis.POSIXct

Hi is there a automatic way that long distances between points are not connected. I have something like plot(x,y,type="o",...) atx <- seq(as.Date("2009-04-01"),as.Date("2011-04-01"),"month") axis.Date(1, at=atx,labels=format(atx, "%b\n%Y"), padj=0.5 ) but I do not want lines between points whose distance is greater than two weeks. thx

Hi I would like to have something like str <- "df$JT == 12" fun <- function(df) { b <- eval(parse(str)) return(b) } but for performance "eval(parse(a))" should not be evaluated at each function call, but should work as fun <- function(df) { b <- df$JT == 12 return(b) } Do you have an idea how I can implement this? Thx Christof

Hi there are some predefined self-start functions, like SSmicmen, SSbiexp, SSasymp, SSasympOff, SSasympOrig, SSgompertz, SSflp, SSlogis, SSweibull, Quadratic, Qubic, SSexp (nlrwr) Btw, do you know graphic examples for this functions? The SSexpDecay (exponential decay) for y = (y0 - plateau)*exp(-k*x) + plateau from

Hi how would you save conditions like a = "day > 100"; b = "val < 50"; c = "year == 2012" in a list? I like to have variables like "day", "val", "year" and a list of conditions list(a,b,c). Then I want to check if a & b & c is true or if a | b | c is true or similar things. Greetings Christof

Hi xyplot(y ~ x | subject) plots a separate graph of y against x for each level of subject. But I would like to have an own function for each level. Something like xyplot(y ~ x | subject, panel = function(x,y) { panel.xyplot(x,y) panel.curve(x,y) { # something that dependents on the current subject ... } }) How I get the current

Hi one col in my Excel file contains many numbers. But on line 3000 and some other lines are strings like "FG 1". "RODBS" seems to omit this lines. "gdata" works, but is much slower. Is this a bug of RODBC or do I apply it wrong? Example with the same "file.xlsx" library(RODBC); excel <- odbcConnectExcel2007("file.xlsx") tab <-

Hi I would like to shorten mod1 <- nls(ColName2 ~ ColName1, data = table, ...) mod2 <- nls(ColName3 ~ ColName1, data = table, ...) mod3 <- nls(ColName4 ~ ColName1, data = table, ...) ... is there something like cols = c(ColName2,ColName3,ColName4,...) for i in ... mod[i-1] <- nls(ColName[i] ~ ColName1, data = table, ...) I am looking forward to help Christof

Hi, a have some code like myfunc <- function(x) { ...; return c(a,b) } ys <- sapply(0:100,myfunc) so I get something like c(c(a1,b1),c(a2,b2),...) But now I need the "as" and "bs" in one vector as <- apply(ys, function(c(a,b)) a) bs <- apply(ys, function(c(a,b)) b) Can you help me with the correct syntax, instead of my pseudo code? thx Christof

Hi I want to add a row to a "data.table" in each round of a for loop. "rbind" seems to be a inefficient way to implement this. How would you do this? The "slow" solution: library(data.table) Rprof("test.out") dt <- data.table() for (i in (1:10000)) { # algorithm that generates a list with different values, # but same key-names, each round, for

Hi, I want to fit nonlinear dose-response curves, as "fun(X,a,b,c)", for each of our 5 trail locations. Our data basis is something like location plot year dose response For each location there are 4 plots as repetitions (over 3 years). So the interactions "location*year" and "location*plot" should be random effects. There are some examples in "Mixed-Effects

Hi I have "observations" obs <- (11455, 11536, 11582, 11825, 11900, ...) and a simulation function f(A,B,C,D,E,F), so sim <- f(A,B,C,D,E,F) e.g. sim = c(11464, 11554, 11603, 11831, 11907, ...) now I would like to fit A,B,C,D,E,F such that "obs" and f(A,B,C,D,E,F) match as well as possible. A,..,F should be integers and have bounds. How would you solve this problem

Hi, I want to plot with axis.Date(), but something is scaled incorrectly. The red vertical line in is put on a totally wrong position. (sample below) Do you have an idea what I'm doing wrong? Thx Christof x11(width=30, height=20) x<-seq(as.Date("2010-02-27"), as.Date("2011-03-28"),"month") y <- seq(0,100,length=length(x)) plot(y ~ x,

Hi I want to do something like a <- c(10,20,15,43,76,41,25,46) tab <- data.frame(a) name <- "a" for (v in unique(tab[[name]])) { r <- subset(tab, name==v) # this does not work ... } i.e. a "string" on the left side of the select expression (subset). How could I solve this? thx Christof

Hi, mod <- lme(A ~ -1 + B+C+D+E+F+G, random = ~1 | ...) results in summary(mod)$coeff B C D E F G (Intercept) b c d e f g i Now I'm interested in the function f <- function(B,C,D,E,F,G) <- { return(i + b*B + c*C + d*D + e*E + f*F + g*G) } Is there a easier way to create such function with flexible number of coefficient, than do it by hand? thx Christof

Hello, I'm having problems working with date values in POSIXct format. Here is what I got (eg.lig attached): x <- read.table("eg.txt", sep = ',', col.names=c("ok","time","secs","lig")) # it gives time as factor z <- cbind(x,colsplit(x$time, split="\\s", names=c("date", "clock")))

Hi, For a project I try to keep everything in normal time, not daylight saving time, to prevent problem when instruments collected data during the nights when we go from DST to normal time. But sometimes R tricks me and I do not know how to prevent it. This is one example: lights_on = as.POSIXct(c("2011-05-06 04:09:26", "2011-05-07 04:07:53", "2011-05-08

Hello everyone, I'm having a big trouble with which seems to be a bug in as.POSIXct() date-time conversion. I have massive GPS datasets in which each location has it's own date and time attribute. As I convert them to POSIXct format, 1300 cases (of about half a million locations) simply return NA values. I picked up a small sample of failed cases and normal cases to demonstrate the

I was trying to convert a vector of POSIXct into a list of POSIXct, However, I had a problem that I wanted to share with you. Works fine with, say, numeric: > v = c(1, 2, 3) > v [1] 1 2 3 > str(v) ?num [1:3] 1 2 3 > l = as.vector(v, mode="list") > l [[1]] [1] 1 [[2]] [1] 2 [[3]] [1] 3 > str(l) List of 3 ?$ : num 1 ?$ : num 2 ?$ : num 3 If you try it with POSIXct,

From POSIXct to numeric and back with time zone I am running regressions on data which has time series with different time resolution. Some data has hourly resolution, while most has either daily or weekly resolution. Aggregation is used to make the hourly data daily, while liner interpolation is used to find daily data from the weekly time series. This data manipulation requires some careful

Hi there are some good tips in "The R Inferno" http://www.burns-stat.com/documents/books/the-r-inferno/ or connect C++ to R with Rcpp http://dirk.eddelbuettel.com/code/rcpp.html or byte code compiler (library(compiler)) or library(data.table) but do you have an idea to fasten standard R source code, with the following Rprof output self.time self.pct total.time