Posts Tagged ‘ R Graphics ’

knitr: Elegant, flexible and fast dynamic report generation with R

December 1, 2011
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The world has changed. You can feel it on GitHub. You can smell it on Google+. For those who have been struggling with Sweave, here comes the knitr package. It has features that you have been longing for, and features that you might have never imagined. Thumb through the PDF manual to see some of

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Graphically analyzing variable interactions in R

August 23, 2011
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Graphically analyzing variable interactions in R

I studied Ecology as an undergraduate, which meant I spent a lot of time gathering and analyzing field data. One of the basic tools we used to look for relationships in a large set of variables was correlation and scatterplot matrices. Each of these ...

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Produce Authentic Math Formulas in R Graphics

April 30, 2011
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Produce Authentic Math Formulas in R Graphics

I remember a few weeks ago, there was a challenge in the R-help list to make the prime symbol in R graphics. In LaTeX, we simply write $X'$ or $X^\prime$. R has a rough support for math expressions (see demo(plotmath)) and they are certainly unsatisfactory for LaTeX users. In fact we can write native LaTeX

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New versions of GGobi and rggobi for Windows users

April 8, 2011
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or those who have been struggling with the installation of GGobi and the rggobi package under Windows: a major update of GGobi 2.1.9 is that GTK+ has been bundled with GGobi, so the installation of GTK+ is no longer required (I recommend you to uninstall it if it is not used elsewhere in your system);

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Review of “R Graphs Cookbook” by Hrishi Mittal

January 24, 2011
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Review of “R Graphs Cookbook” by Hrishi Mittal

Executive summary: Extremely useful for new users, informative to even quite seasoned users. Refereeing Once upon a time a publisher asked if I would referee a book (unspecified) about R.  In an instance that can only be described as psychotic I said yes.  That bit of insanity turned out to be a good thing. I … Continue reading...

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Happy New Year with R (2011, Fireworks!)

January 1, 2011
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Happy New Year with R (2011, Fireworks!)

ast year I posted an animation created in R to celebrate the new year, and this year I’ve got a more fabulous animation. Unfortunately our Lord of CRAN (Kurt) has been out of office for several days, so I’m unable to publish my animation package on CRAN as scheduled. Anyway, for those who are curious

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A Special Graphics Device in R: the Null Device

December 22, 2010
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It is well-known that R has several graphics devices — either the screen devices (X11(), windows(), …) or the off-screen devices (pdf(), png(), …). We can query the default graphics device in options(): getOption('device') In a non-interactive session, the default device is pdf(). This is why Sweave has to create a file named Rplots.pdf no

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Climate Oscillations and GISS Temperature Anomaly Trends

April 27, 2010
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Climate Oscillations and GISS Temperature Anomaly Trends

In this post, I examine the combined impacts of Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO) and El Nino – Southern Oscillation (ENSO)   on the long-term GISS Land and Ocean Temperature Anomaly (LOTA) trend. Introduction Professor Don Easterbrook of … Continue reading →

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alphahull: an R Package for Alpha-Convex Hull

April 16, 2010
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alphahull: an R Package for Alpha-Convex Hull

new paper on the α-convex hull appeared in the Journal of Statistical Software today (http://www.jstatsoft.org/v34/i05/paper). The α-convex hull is an interesting problem which caught my attention long time ago but I didn’t know a solution then. R has a function chull() which can generate (indices of) the convex hull for a series of points. Now

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Demonstrating the Power of F Test with gWidgets

April 2, 2010
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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 vary,

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