search for: loecher

...ld get the C source code to compute pnbinom() and qnorm() ? (I would use R in batch mode but I find the startup time prohibitive, unless there is a way to speed it up) I searched the Web and it clearly is part of the R distribution, I just don't know how to extract them. Thanking you ! Markus Loecher Princeton, NJ [[alternative HTML version deleted]]

Dear R users, I have been diligently using the apply() family in order to avoid explicit for loops and speed up computation. However, when I finally inspected the source code for apply, it appears that the core computation is a simple loop as well. What am I missing ? Why the often found advice to use apply() instead of loops and the actually observed empirical speedups on many tasks ? Thanks in

The MASS package is listed on the CRAN web site ( http://cran.r-project.org/web/packages/MASS/index.html) but I am unable to install it via install.packages(). The error is that the package is "unavailable". When I manually download the source tar ball and try to install it on a Linux machine, installation fails because "it is not a valid package". Do I need to search

Dear R community, pardon my ignorance but how would you get the source code for"non-visible functions" ? For example, I would like to see and modify the source code for the prompt() function. Thanks! Markus [[alternative HTML version deleted]]

Dear R users, I had somehow expected that read.table() would treat the column specified by the row.names argument as of class character. That seems to be the only sensible class allowed for a column containing row names. However, that does not seem to be the case, as the following example shows: x <- cbind.data.frame(ID = c("010007787048271871", "1007109516820319",

Full_Name: Markus Loecher Version: 1.1.1 OS: Solaris Submission from: (NULL) (129.73.1.1) When trying to install R on a Sun SPARC, make fails in the very end, here is the error message: rbitmap.c:239: parse error before `jmp_buf' rbitmap.c:239: warning: no semicolon at end of struct or union rbitmap.c: In function `m...

Hi, I am trying to avid the somewhat costly startup overhead of launching a separate R executable for each "client" request on Linux. My current architecture is such that My Java client explicitly calls R in batch mode and passes it certain parameters. The initital startup takes almost 10 seconds because R has to load a bunch of libraries as well as a moderately large, previously

Dear R graphics experts, Do you know of any way of plotting semi-transparent points in R ? I face this problem any time I want to e.g. plot thousands of points that belong to two or three classes which I color code. With the default opaque colors, the plotting order matters and basically the points I plot last completely dominate the picture. I would much rather have the overlaying points

Dear list members, I switched from Splus to R a few years ago and so far found no functionality missing. However, I am struggling to find the equivalent align() function for time series. I did find some reduced functionality such as alignDailySeries in package:fCalendar but the full capability of aligning two timeseries seems to be missing. Could this be true ? I am sure there must be a need

Dear list members, I use both R and Matlab and find that each has its own strengths. Matlab definitely has the edge when it comes to the interactivity of its graphs. In addition I find the little operator end extremely useful in indexing arrays. (as in x(1:end,) ) The notation is MUCH more cumbersome in R using nrow() and ncol() recursively (as in x[1:nrow(x), ] ). Is there a package that might

Dear R users, I am struggling a bit with the converting dates to full POSIX timestamps, in particular, I would like to somehow force the timezone to be local, i.e. the output of as.POSIXct(as.Date("2008-07-01")) should always be equal to "2008-07-01 00:00:00", is that achievable ? I tried to set the origin and the timezone, neither of which seems to make a difference. On my Mac

Dear gbm users, When running predict.gbm() on a "large" dataset (150,000 rows, 300 columns, 500 trees), I notice that the memory used by R grows beyond reasonable limits. My 14GB of RAM are often not sufficient. I am interpreting this as a memory leak since there should be no reason to expand memory needs once the data are loaded and passed to predict.gbm() ? Running R version 2.9.2 on

Dear mixed effects modelers, I seem unable to find a predict method for mer objects in the package lme4. Am I not seeing the forest for the trees ? Any pointer would be very helpful. Thanks, Markus [[alternative HTML version deleted]]

Dear ggplot2 users, is there an easy/elegant way to suppress zero count bars in histograms with logarithmic y axis ? One (made up) example would be qplot(exp(rnorm(1000))) + geom_histogram(colour = "cornsilk", fill = "darkblue") + scale_x_sqrt() + scale_y_log10() Thanks! Markus [[alternative HTML version deleted]]

Dear fellow R users, I read through the "Writing R Extensions" document and am able to now create my own packages/libraries which so far are just well documented collections of my own R functions. I use package.skeleton() and the tools package to build these packages. However, it is not clear to me how to modify and update a package after its initial creation. How do you elegantly update

Dear all, the help file for predict.gbm states that "The predictions from gbm do not include the offset term. The user may add the value of the offset to the predicted value if desired." I am just not sure how exactly, especially for a Poisson model, where I believe the offset is multiplicative ? For example: library(MASS) fit1 <- glm(Claims ~ District + Group + Age +

Dear R users, I am trying to fully understand the difference between estimating overdispersion with glm.nb() from MASS compared to glm(..., family = quasipoisson). It seems that (i) the coefficient estimates are different and also (ii) the summary() method for glm.nb suggests that overdispersion is taken to be one: "Dispersion parameter for Negative Binomial(0.9695) family taken to be

Dear R users, while I enjoy the built-in log argument to the plot() function, I wished it would be as easy to create more general custom transformed axes such as sqrt(), logit, etc... for example, instead of plot(x=exp(rnorm(10)), y=(1:10)^4, log = "xy"), sth. along the lines of plot(x=exp(rnorm(10)), y=(1:10)^4, trans = list(x = log, y = sqrt)) to encode the desired transfomation.

Dear all, I am struggling to modify the axis labels/ticks in a panel provided to xyplot. To begin with, I do not know the equivalent of the xaxt="n" directive for panels that would set the stage for no default x axis being drawn. My goal is to draw ticks and custom formatted labels at certain hours of the week. When I execute the code below, I get an error message in the plot window that

...portunity to work in a dynamic team in our Manhattan office. This will be a consulting arrangement but could potentially lead to a long term relationship. We are looking to fill this position as soon as possible. Please send your resume and cover letter to info at sensenetworks.com Thanks, Markus Loecher Lead Scientist Sense Networks [[alternative HTML version deleted]]