similar to: Sparse dataframes?

I have a humongous csv file containing census data, far too big to read into RAM. I have been trying to extract individual columns from this file using the colbycol package. This works for certain subsets of the columns, but not for others. I have not yet been able to precisely identify the problem columns, as there are 731 columns and running colbycol on the file on my old slow machine takes

Is there any way to search the console during an interactive session? I've looked and looked, and can not find one. In some add-on package, maybe? Sorry to be so basic, but help would be greatly appreciated. andrewH -- View this message in context: http://r.789695.n4.nabble.com/Searching-the-console-tp3797884p3797884.html Sent from the R help mailing list archive at Nabble.com.

Dear folks-- Suppose I have an expression that evaluates to a string, and that that string, were it not a character vector, would be a symbol. I would like a function, call it doppel(), that will take that expression as an argument and produce something that functions exactly like the symbol would have if I typed it in the place of the function of the expression. It should go as far along the

Dear folks -- There are a number of functions -- I am thinking of str() as an example -- that produce text as a side-effect, rather then returning it. Is there any way to send the text produced by such functions into a character variable? Any suggestions would be greatly appreciated. andrewH -- View this message in context:

Dear folks ? I have a large (26 gig) ASCII flat file in fixed-width format with about 10 million observations of roughly 400 variables. (It is 51 years of Current Population Survey micro data from IPUMS, roughly half the fields for each record). The file was produced by automatic process in response to a data request of mine. The file is not accompanied by a human-readable file giving the

I have a couple of hundred American Community Survey Summary Files files containing rectangular arrays of data, mainly though not exclusively numeric. Each file is referred to as a sequence (henceforth "seq"). From these files I am trying to extract particular subsets (tables) consisting of a sets of columns. These tables are defined by three numbers (now in columns in a data frame):

There is something that I wish I had that I think would help me a lot to be a better R programmer, that I think would probably help many others as well. I put the wish out there in the hopes that someone might think it was worth doing at some point. I wish I had the code of some substantial, widely used package ? lm, say ? heavily annotated and explained at roughly the level of R knowledge of

Dear Folks-- I'm trying to make a function that takes the columns I select from a data frame and then uses a for loop to print some information about each one, starting with the column name. I succeed in returning the column name, but nothing else I have tried using the variable colName, containing the name of the column, to refer to the column itself has worked. Below I show my

Dear folks? Is there a function to correctly find (and count) the NAs in a factor when exclude=NULL, regardless of whether their origin is in the original data or by subsequent assignment? In example number 1 below, where NAs are assigned by is.na()<-, testing the factor with is.na() finds the correct number of NAs. In example number 2, where the NAs are from the data, neither is.na(), ==NA,

ear folks ? I have a question, though it is more of a logic- or a good practices-question than a programming question per se. I am working with data from the American Community Survey summary file. It is mainly categorical count data. Currently I am working with about 40 tables covering about 35 variables, mainly in two-way tables, with some 3-way and a handful of four-way tables. I am going to

Dear folks, I?m trying to build a function to create and make available some variables I frequently use for testing purposes. Suppose I have a function that takes some inputs and creates (internally) several named objects. Say, fun1 <- function(x, y, z) {obj1 <- x; obj2 <- y; obj3 <- z <missing stuff> } Here is the challenge: After I run it, I want the objects to be

Dear list members, I can't figure out how get 'xyplot' or 'dotplot' in the 'lattice' package to respect the 'lwd' value for specifying the border with for *symbols* (for lines it works fine). Example: ----- # Base graphics works fine (gives a 'fat? circle) plot(5, cex=10, pch=21, lwd=10) # But 'xyplot' or 'dotplot' doesn't

Using str() in a function. I am in the early phase of learning R, and I find I spend a lot of time trying to figure out what is actually in objects I have created or read in from a file. I'm trying to make a simple little function to display a couple of things about a object, let's say the summary() and the str(), sequentially, preferably without a bunch of surplus lines between them. I

Dear all, I'm trying to improve the documentation I provide my R packages, and to that end I'd like to find out what you think is great R documentation. I'm particularly interested in function documentation, but great vignettes, websites or book are also of interest. What is your favourite bit of R documentation, and why? Thanks, Hadley

Dear Folk-- Suppose I have some objects A, B & C, and a function getDots <- function(...) {args <- list(...) etc.} If I do a call to getDots(A, B, C) then the variable args will be assigned to a list which contains the objects to which A, B & C refer, but which will not (except by happenstance) contain the names A, B, or C. I would like getDots to return a named list, with the

Hi WizaRds, I'd like to overplot UK fuel consumption per quarter over the course of five years. Sounds simple enough? Unless I'm missing something, the following seems very involved for what I'm trying to do. Any suggestions on simplifications? The way I did it is awkward mainly because of the first call to plot ... but isn't this necessary, especially to set limits for the

Dear folks: Let?s suppose I want a function to print return the name of the object passed to it. > myname <- function(object) {out<-deparse(substitute(object)); out} This works fine on a single object: > O1 <-c(1:4) > myname(O1) [1] "O1" However it does not work if you use lapply to pass it the same object from a list: > O2 <-c(1:4) > object.list <-

Dearfolks-- I have been told by an experienced R programmer and teacher whom I trust that it is easier to understand R code if you read it aloud, as the language that it is. However, she was clear that reading it aloud was not simply reading the marks on the screen: you read A.df[5,] as "the fifth row of A.df" (or "the fifth row of data frame A"), not as "A dot df left

Hello, A made a xyplot using the lattice library in R (latest version). The publisher of our paper has requested: 1. all tick marks should point inwards instead of outwards. 2. All lines should be thicker (lines, axes, boxes, etc. Everything). Lines is easy...I used: lwd=1.5 but what about the lines of the axes, and the lines that build up the plot itself?....? Any

Dear folks-- The function below is a snippet of a larger function that is not doing what it is supposed to do, and I do not understand its behavior. The larger function is supposed to produce an array containing the results of a user-specified function applied to groups of data defined by the intersection of one or more factors, and return them in an array with a dimension for each factor and a