similar to: "rounding" to a number that is LOWER than my number

Dear all, I have a function that predicts DV based on one predictor pred: pred<-c(0,3000000,7800000,15600000,23400000,131200000) DV<-c(0,500,1000,1400,1700,1900) ## I define Function 1 that computes the predicted value based on pred values and parameters a and b: calc_DV_pred <- function(a,b) { DV_pred <- rep(0,(length(pred))) for(i in 1:length(DV_pred)){ DV_pred[i] <- a *

Hello! I have a list of variable length. One example is: X=vector("list",3) X[[1]]=1:2 X[[2]]=1:2 X[[3]]=1:2 How could I run expand.grid on the elements of X so that the results would be the same as expand.grid(1:2,1:2,1:2)? Thank you! Dimitri -- Dimitri Liakhovitski gfk.com <http://marketfusionanalytics.com/> [[alternative HTML version deleted]]

Hello! I have a data frame with some NAs. test<-data.frame(a=c(1,2,NA),b=c(10,NA,20)) I need to sum up values in 2 variables. However: test$a+test$b procudes NAs in rows that have NAs. How could I sum up columns while ignoring NAs (the way the function sum(..., na.rm=T) works? Thank you! -- Dimitri Liakhovitski marketfusionanalytics.com

Hello! I've tried for a while - but can't figure it out. I have data frame x: y=c("a","b","c","d","e") z=c("m","n","o","p","r") a=c(0,0,1,0,0) b=c(2,0,0,0,0) c=c(0,0,0,4,0) x<-data.frame(y,z,a,b,c,stringsAsFactors=F) str(x) Some of the values in columns a,b, and c are >0: I need to

Hello! I am trying to identify which ones of a vector of dates are US holidays. And, ideally, which is which. And I do not know (a-priori) which dates those should be. I have, for example: x<-seq(as.Date("2011-01-01"),as.Date("2011-12-31"),by="day") (x) I think chron should help me here - but maybe I am not using it properly: library(chron) is.holiday(chron) #

Hello! I have a large data frame x: x<-data.frame(item=letters[1:5],a=1:5,b=11:15) # in actuality, x has 1000 rows x$item<-as.character(x$item) I also have a small data frame y with just 1 row: y<-data.frame(item="f",a=3,b=10) y$item<-as.character(y$item) I have to decide if y$a is larger than the smallest of all the values in x$a. If it is, I want y to replace the whole

Hello! # I have a list with several data frames: mylist<-list(data.frame(a=1:2,b=2:3), data.frame(a=3:4,b=5:6),data.frame(a=7:8,b=9:10)) (mylist) # I want to grab only one specific column from each list element neededcolumns<-c(1,2,0) # number of the column I need from each element of the list # Below, I am doing it using a loop: newlist<-NULL for(i in 1:length(mylist) ) {

Hello! I have 2 maps - both created in ssplot and both identical in terms of outline. Is there any way to superimpose Map1 (which has black borders between Canadian provinces) onto Map2 (which is also a map of Canada)? Thanks a lot for your hints! Dimitri ### A. Reading in Canada data at the province and then at the county level: library(raster) getData('ISO3') # Canada's code is

Hello! I have a data set: set.seed(123) y<-data.frame(week=seq(as.Date("2010-01-03"), as.Date("2011-01-31"),by="week")) y$var1<-c(1,2,3,round(rnorm(54),1)) y$var2<-c(10,20,30,round(rnorm(54),1)) # All I need is to create lagged variables for var1 and var2. I looked around a bit and found several ways of doing it. They all seem quite complicated - while in

Hello! I am trying to create an R optimization routine for a task that's currently being done using Excel (lots of tables, formulas, and Solver). However, otpim seems to be finding a local minimum. Example data, functions, and comparison with the solution found in Excel are below. I am not experienced in optimizations so thanks a lot for your advice! Dimitri ### 2 Inputs:

Hello! It's a shoot in the dark, but I'll try. If one has a total of 100 (e.g., %), and three components of the total, e.g., mytotal=data.frame(x=50,y=30,z=20), - one could build a pie chart with 3 sectors representing x, y, and z according to their proportions in the total. I am wondering if it's possible to build something very similar, but not on a circle but in a square - such that

I have a dataset where I have missing times (11:00 and 16:00). I would like the outputs to include the missing time so that the final time vector looks like "realt" and has the previous time's value. Ex. If meas at time 15:30 is 0.45, then the meas for time 16:00 will also be 0.45. meas are the measurements and times are the times at which they were taken. meas<-runif(18)

Hi, is there a way to replicate a data.frame like you can replicate the entries of a vector (with the repeat-function)? I want to do this: x <- data.frame(x, x) (where x is a data.frame). but n times. And it should be as cpu / memory efficient as possible, since n is pretty big in my case. thanks for any suggestions!

Hello! I have a data frame with several rows, for example: x=as.data.frame(matrix(c(1,2,3, 1,2,3, 1,2,2, 1,2,2, 1,1,1),ncol=3,byrow=T)) I would like to find y - a data frame that only has the unique rows from x, i.e.: 1,2,3 1,2,2 1,1,1 Thanks a lot for your hints! Dimitri -- Dimitri Liakhovitski gfk.com <http://marketfusionanalytics.com/> [[alternative HTML

Dear all, I have one problem and did not find any solution.(I have also attached the problem in text file because sometimes column spacing is not good in mail) I have a file(file.txt) attached with this mail.I am reading it using this code to make a data frame (file)- file=read.table("file.txt",fill=T,colClasses = "character",header=T) file looks like this- Chr Pos

Hello! I have dates for the beginning of each week, e.g.: weekly<-data.frame(week=seq(as.Date("2010-04-01"), as.Date("2011-12-26"),by="week")) week # each week starts on a Monday I also have a vector of dates I am interested in, e.g.: july4<-as.Date(c("2010-07-04","2011-07-04")) I would like to flag the weeks in my weekly$week that

Sorry if it's been discussed before - don't seem to find it. I'd like to calculate a mean while ignoring zeros. "mean" doesn't seem to have an option for that. Any other function/package that could do it? Thanks for a pointer! -- Dimitri Liakhovitski marketfusionanalytics.com

Hello! Hope you could help me split the strings. I have a set of strings: x<-c("name_a1_2.5.o","name_a2_2.53.o","name_a3_bla_1.o") I need to extract from each string: 1. Its unique part that comes before the last "_", i.e.: "a1","a2","a3_bla". 2. The part that comes after the last "_" and before ".o"

Hi, how can I print "<=" (I mean the symbol of just one character) in the main title of a plot? for example: plot(1:10, main=paste("x <=", x)) where variable x is some number generated on the fly. Thanks John

Dear R-users I need to fit a nonlinear model to a piece of data. The model to be fitted uses past values of the input and the ouput - something like y(k) ~ f(y(k-1),y(k-2),u(k),u(k-1) ....) (k is time index). As far as I know I could use earth(MARS), nnet and etc but I am not sure how to deal with the past values since most, if not all, examples I saw formula does not take in account past