Monthly Archives: March 2010

Using vectors to customize placement of tick marks and labels on a plot

March 24, 2010
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Using vectors to customize placement of tick marks and labels on a plot

OK, let's say you want to create a plot and you need an easy way to specify where along the scale your tick marks and labels land, as opposed to having R just decide itself. An easy way to do that is to create a vector and assign the axis characteristi...

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A Demo for the Ratio Estimation in Sampling Survey (Animation)

March 24, 2010
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A Demo for the Ratio Estimation in Sampling Survey (Animation)

mber Watkins gave me a suggestion on the animation for the ratio estimation, and I think this is a good topic for my animation package. I’ve finished writing the initial version of the function sample.ratio() for this package, which will appear in the version 1.1-2 a couple of days later. As we know, the benefit

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ECG Signal Processing

March 24, 2010
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ECG Signal Processing

After reading (most of) “The Scientists and Engineers Guide to Digital Signal Processing” by Steven W. Smith, PhD, I decided to take a second crack at the ECG data. I wrote a set of R functions that implement a windowed (Blackman) sinc low-pass filter. The convolution of filter kernel with the input signal is conducted

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Statistical learning with MARS

March 24, 2010
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Steve Miller at the InformationManagement blog has been looking at predictive analytics tools for business intelligence applications, and naturally turns to the statistical modeling and prediction capabilities of R. Says Steve: The R Project for Statistical Computing continues to dazzle in the open source world, with exciting new leadership at Revolution Computing promising to align commercial R with business...

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RXQuery

March 24, 2010
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RXQuery

I have put a new version of the RXQuery package which interfaces to the Zorba XQuery engine. This makes the package compatible with the 1.0.0 release of Zorba for external functions. The package allows one to use XQuery from within R and to use R fu...

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Lessons Learned from EC2

March 24, 2010
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Lessons Learned from EC2

A week or so ago I had my first experience using someone else’s cluster on Amazon EC2. EC2 is the Amazon Elastic Compute Cloud. Users set up a virtual computing platform that runs on Amazon’s servers “in the cloud.” Amazon EC2 is not just another cluster. EC2 allows the user to create a disk image containing an operating system...

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Font Families for the R PDF Device

March 24, 2010
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otivated by the excellent R package pgfSweave, I begin to notice the font families in my graphs when writing Sweave documents. The default font family for PDF graphs is Helvetica, which is, in most cases (I think), inconsistent with the LaTeX font styles. Some common font families are listed in ?postscript, and we can take

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oro.nifti 0.1.4

March 24, 2010
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The latest release of oro.nifti (0.1.4) has been released on CRAN.  New features include:Added text capability in the (unused) fourth pane in orthographic()A vignette is now included (taken from dcemriS4)

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oro.nifti 0.1.4

March 24, 2010
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The latest release of oro.nifti (0.1.4) has been released on CRAN.  New features include:Added text capability in the (unused) fourth pane in orthographic()A vignette is now included (taken from dcemriS4)

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oro.dicom 0.2.5

March 24, 2010
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The latest version of oro.dicom (0.2.5) has been released on CRAN.  New features include:Added "mosaic" capability when creating 3D arrays from DICOMdicomTable() now accepts single DICOM fileBetter handling of SequenceItem tags when reading in DIC...

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