regor Gorjanc published an interesting article “Using Sweave with LyX” in R News in 2008, which (I believe) makes it much easier to use Sweave. I use command-line tools a lot every day, but I am still “GUI-addicted”. (I don’t want to comment more about Microsoft Word here.) LyX is ... [Read more...]

ables are pretty common in web pages as data sources, and the most direct way to get these data is probably to copy and paste. This is OK if there are only two or three tables, and when we need to grab 5000 tables in 1000 web pages, we may not really ... [Read more...]

his blog post is mainly for Stat 579 students on the homework for week 7, since I received too many “gory” loops in the homework submissions and I think it would help a bit to write my thoughts on R loops for beginners. The immortal motto for newbies in programming is: If ... [Read more...]

One of my readers asked two weeks ago how to control two graphics windows with the slider in gWidgets. Here is a simple example: if (!require("gWidgetsRGtk2")) install.packages("gWidgetsRGtk2") library(gWidgetsRGtk2) options(guiToolkit = "RGtk2") graphics.off() x11() x11() dev.set() gslider(from = 1, to = 100, value = 10,     container = gwindow("Two Plotting Windows"), ... [Read more...]

It is not uncommon to see messy R code which is almost not human-readable like this: # rotation of the word "Animation" # in a loop; change the angle and color # step by step for (i in 1:360) { # redraw the plot again and again plot(1,ann=FALSE,type="n",axes=FALSE) # rotate; use ... [Read more...]

e know the real distribution of the F statistic in linear models — it is a non-central F distribution. Under H0, we have a central F distribution. Given 1 – α, we can compute the probability of (correctly) rejecting H0. I created a simple demo to illustrate how the power changes as other parameters ... [Read more...]

hen we want to call external programs in R under Windows, we often need to know the paths of these programs. For instance, we may want to know where ImageMagick is installed, as we need the convert (convert.exe) utility to convert images to other formats, or where OpenBUGS is ... [Read more...]

Here are some (trivial) R tips in the course Stat 511. I’ll update this post till the semester is over. Formatting R Code Reading code is pain, but the well-formatted code might alleviate the pain a little bit. The function tidy.source() in the animation package can help us format ... [Read more...]

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hash-2.0.0 has been released please read about it here: Earlier today, hash-1.99.x was released to CRAN. This is a stable release and adds some more functions to an already full-featured hash implementation. This version fixes some bugs, adds some features, improves performance and stability. You can read about the ... [Read more...]

Download Code Like A Pirate - The #rstats Appliance from the SUSE Gallery  The R programming language was featured about a year ago in a New York Times article (http://bit.ly/iaqQ). I've been an R user since 2000, so I've collected some resources ... [Read more...]

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ince animation 1.0-9, we will be able to create a PDF document with an animation embedded in it; the function is saveLatex(), and its usage is similar to saveMovie() and saveSWF(): you pass an R expression for creating animations to this function, and this expression will be evaluated in the ... [Read more...]

s Sir Francis Bacon said, “Histories make men wise; poets witty; the mathematics subtile; natural philosophy deep; moral grave; logic and rhetoric able to contend.” And Windows stupid. He should have added the last sentence if he were a Windows user in this age. 1. Avoid Using M$ Excel A lot ... [Read more...]

anping Chen raised a question in the Chinese COS forum on the output of Eviews: how to (re)format the decimal coefficients in equations as text output? For example, we want to round the numbers in CC = 16.5547557654 + 0.0173022117998*PP + 0.216234040485 * PP(-1) + 0.810182697599 * (WP + WG) to the 3rd decimal places. [...] [Read more...]

inlin Yan posted a cool (hot?) simulation of burning fire with R in the COS forum yesterday, which was indeed a warm welcome. I’m not sure whether our forum members will be scared by the “fire” under the title “Welcome to COS Forum”. The fire was mainly created by ... [Read more...]

ag cloud is a bunch of words drawn in a graph with their sizes proportional to their frequency; it’s widely used in blogs to visualize tags. We can observe important words quickly from a tag cloud, as they often appear in large fontsize. Tony N. Brown asked how to “... [Read more...]

After a few hours’ work, I modified the function tidy.source() in the animation package so that it can preserve complete comment lines. See the tidy.source() wiki page for example. tidy.source [Read more...]

In a comment on my first post on design flaws in the R language, Longhai remarked that he has encountered problems as a result of R’s default behaviour of dropping a dimension of a matrix when you select only one row/column from that dimension. This was indeed the ... [Read more...]

The R language for statistical computing has become the standard for academic statistical research, for the very good reason that it’s better than the alternatives. It’s far from perfect however. I could come up with a long “wish list” of desired features it lacks, but that’s not ... [Read more...]