Set your R working directory in TextWrangler

Set your R working directory in TextWrangler

Yesterday I figured out (together with a friend, Leendert) how to set your R working directory to the path of the current document you're working on in TextWrangler. We developed two scripts: one for setting the working directory of R directly, and one...

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R Community in Australia

September 17, 2009
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R Community in Australia

One of the nice aspects of R is the community of users that has built up around it. The open-source model seems to create an orientation of sharing and contribution. Users benefit from R and then they give back in the form of new packages, free documen...

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Workflow in R

September 17, 2009
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Workflow in R

This came up recently on StackOverflow. One of the answers was particularly helpful and I thought it might be worth mentioning here. The idea presented there is  to break the code into four files, all stored in your project directory. These four files are to be processed in the following order. load.R This file includes

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Workflow in R

September 17, 2009
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This came up recently on StackOverflow. One of the answers was particularly helpful and I plan to adopt this for my future work. In fact, it is close to what I already do, but is a little more structured. The idea is to break the code into four files, ...

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Solar Trends: Sunspot Numbers Since 1749

September 17, 2009
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Solar Trends: Sunspot Numbers Since 1749

This is the 1st in a series of  posts I will be doing on solar trends. In this post, I show how to retrieve online monthly sunspot data back to 1749, calculate average annual sunspot numbers (SSN),  plot the monthly and annual average SSN as well as a lowess smooth, add the Solar

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Example 7.12: Calculate and plot a running average

September 17, 2009
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Example 7.12: Calculate and plot a running average

The Law of Large Numbers concerns the stability of the mean, as sample sizes increase. This is an important topic in mathematical statistics. The convergence (or lack thereof, for certain distributions) can easily be visualized in SAS and R (see also Horton, Qian and Brown, 2004).Assume that X1, X2, ..., Xn are independent and identically distributed realizations...

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Comments on “Introduction to Scientific Programming and Simulation Using R”

September 17, 2009
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Comments on “Introduction to Scientific Programming and Simulation Using R”

I've just been reading Introduction to Scientific Programming and Simulation Using R by Owen Jones, Robert Maillardet, and Andrew Robinson. It seems like it would make a good introductory book for a course on, as the title suggests, scientific programm...

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R clinic this week: Regression Modeling Strategies in R

September 16, 2009
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At this week's R clinic Frank Harrell will unveil the new rms (Regression Modeling Strategies) package that is a replacement for the R Design package.  He will demonstrate the differences with Design, especially related to enhanced graphics for displaying effects in regression models.  Frank will also discuss the implementation of quantile regression in rms.  The rms package website has...

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Multiple Linear Regression

September 14, 2009
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Multiple Linear Regression

A multiple linear regression (MLR) model that describes a dependent variable y by independent variables x1, x2, ..., xp (p > 1) is expressed by the equation as follows, where the numbers α and βk (k = 1, 2, ..., p) are the parameter...

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Find the function you’re looking for in R

September 14, 2009
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Any R user no matter what level of experience has had trouble finding the package or the function to do what you want to do and then figuring out how to use it.  The sos package in R just made that a lot easier. First, fire up R, then install the sos package (don't omit the quotes): install.packages("sos") It'll ask you to...

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Chicago Half Marathon 2009

September 13, 2009
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Today it was once again time for the Chicago Half Marathon (which I have now been running in 2003, 2004, 2005, 2006, 2007 and 2008). Conditions were much much better than last year's very heavy rainfall---we were once again treated to a sunny and clear Chicago sky. It was however a little on the humid side and got...

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Finding an R function

September 13, 2009
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Finding an R function

Suppose you want a function to fit a neural network. What’s the best way to find it? Here are three steps that help to find the elusive function relatively quickly. First, use help.search("neural") or the shorthand ??neural. This will search the help files of installed packages for the word “neural”. Actually, fuzzy matching is used

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Finding an R function

September 13, 2009
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Suppose you want a function to fit a neural network. What’s the best way to find it? Here are three steps that help to find the elusive function relatively quickly. First, use help.search("neural") or the shorthand ??neural. This will search the help...

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New R package: sos

September 12, 2009
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Searching help pages of contributed packages just got easier with the release of the new sos package. This is a replacement for and substantial enhancement of the existing "RSiteSearch" package. To learn more about it, try vignette("sos") We hope...

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CO2: Emissions & Changes in Atmospheric Levels

September 11, 2009
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CO2: Emissions & Changes in Atmospheric Levels

In previous posts, I have shown the 1750-2008 global CO2 emission trends and the atmospheric CO2 concentrations at Mauna Loa, Hawaii. In this post, I compare annual CO2 emissions with annual changes in atmospheric CO2.  The resulting chart shows the portion of CO2 emissions that remains in the atmosphere and the portion that

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MATLAB style stem plot with R

September 10, 2009
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MATLAB style stem plot with R

Recently I wanted to plot an impulse response function with R and missed the MATLAB style stem plot for doing it. I couldn't find an R function for it with a quick Google search so I made my own. So here is the function and a small example: #The function stem <- function(x,y,pch=16,linecol=1,clinecol=1,...){ if (missing(y)){ y = x ...

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MATLAB style stem plot with R

September 10, 2009
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MATLAB style stem plot with R

Recently I wanted to plot an impulse response function with R and missed the MATLAB style stem plot for doing it. I couldn't find an R function for it with a quick Google search so I made my own. So here is the function and a small example: #The function stem <- function(x,y,pch=16,linecol=1,clinecol=1,...){ if (missing(y)){ y = x ...

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Aggregating SSURGO Data in R

September 10, 2009
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Aggregating SSURGO Data in R

  Premise SSURGO is a digital, high-resolution (1:24,000), soil survey database produced by the USDA-NRCS. It is one of the largest and most complete spatial databases in the world; and is available for nearly the entire USA at no cost. These data are distributed as a combination of geographic and text data, representing soil map units and their...

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Machine Learning in R

September 10, 2009
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Revolutions blog recently posted a link to R code by Joshua Reich with self-contained examples of using machine learning techniques in R, including various clustering methods (k-means, nearest neighbor, and kernel), recursive partitioning (CART), principle components analysis, linear discriminant analysis, and support vector machines.  This post also links to some slides that go over the basics

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brew: Creating Repetitive Reports

September 9, 2009
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brew: Creating Repetitive Reports

United Nations report World Population Prospects: The 2008 Revision (highlights available here) provides data about the historical and forecasted population of the country. In exploring the future and past population trends it is relatively easy to subset the dataset by your selected variable. > file <- c("UNdata_Population.csv") > population <- read.csv(file) > names(population) <- c("code", "country", "year", +

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search the graph gallery from R

September 8, 2009
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pre{ font-size:xx-small !important ; border: 1px black solid; } This is a short code snippet that is motivated by this thread on r-help yesterday. The gallery contains a search engine textbox (top-right) that can be used to search for content i...

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new R package : ant

September 8, 2009
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The ant package has been released to CRAN yesterday. As discussed in previous posts in this blog (here and here), the ant R package provides an R-aware version of the ant build tool from the apache project. The package contains an R script that c...

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Comparison between 15 different cities…

September 6, 2009
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Comparison between 15 different cities…

The other day I was thinking about how expensive will it be to live in London (as I'm going to live in London for almost one year), and also thinking about how expensive are the cities where some of my best friends live and I got a report by UBS called "Prices and Earnings 2009", it's all...

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Comparison between 15 different cities…

September 6, 2009
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Comparison between 15 different cities…

The other day I was thinking about how expensive will it be to live in London (as I'm going to live in London for almost one year), and also thinking about how expensive are the cities where some of my best friends live and I got a report by UBS called "Prices and Earnings 2009", it's all...

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Global Mean Sea Level Trends

September 6, 2009
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Global Mean Sea Level Trends

In this post, I show an R script that downloads the University  of Colorado, Boulder’s 1993-2009 global mean sea level (msl) change (link) data, converts the ASCII file into a usable R data frame, calculates moving average and msl change  trend rate and develops a trend  chart that shows msl change  and trend rates

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RQuantLib 0.3.0 Windows build snag

September 6, 2009
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Yesterday's upload of RQuantLib 0.3.0 contained one minor oversight: I had failed to update src/Makefile.win to the new and enlarged set of source files. The proper fix (of using wildcards and implicit rules) was simple, and Uwe Ligges kindly rebuilt...

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RQuantLib 0.3.0 Windows build snag

September 6, 2009
By

Yesterday's upload of RQuantLib 0.3.0 contained one minor oversight: I had failed to update src/Makefile.win to the new and enlarged set of source files. The proper fix (of using wildcards and implicit rules) was simple, and Uwe Ligges kindly rebuilt R...

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RQuantLib 0.3.0 Windows build snag

September 6, 2009
By

Yesterday's upload of RQuantLib 0.3.0 contained one minor oversight: I had failed to update src/Makefile.win to the new and enlarged set of source files. The proper fix (of using wildcards and implicit rules) was simple, and Uwe Ligges kindly rebuilt...

Read more »

RQuantLib 0.3.0 released

September 5, 2009
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Earlier this evening, I rolled up a new version of RQuantLib. It has been pushed to CRAN and Debian, and source and binary version should appear on the respective mirror networks in due course. This version, the first in a new '0.3.*' release seri...

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