892 search results for "how to import image file to r"

Visualizing Baltimore with R and ggplot2: Crime Data

December 7, 2012
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Visualizing Baltimore with R and ggplot2: Crime Data

The advent of municipal open data initiatives has been both a blessing and curse for my particular brand of data nerd. On one hand, it has opened up the possibility of developing deep and useful knowledge about the places we...

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Modis QC Bits

December 5, 2012
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Modis QC Bits

In the course of working through my MODIS  LST project and reviewing the steps that Imhoff and Zhang took as well has the data preparations other researchers have taken ( Neteler ) the issue of MODIS Quality control bits came up.  Every MODIS  HDF file comes with multiple SDS or multiple layers of data. For

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Using TeXmacs as an interface for R (part 1)

December 3, 2012
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Using TeXmacs as an interface for R (part 1)

A nice, but not very well known, interface to R is TeXmacs. (I have to say that I am not totally objective, since I wrote the interface between R and TeXmacs…) Here’s a sample window: In the following few posts I’d like to explain how to use this interface. Installation First, install TeXmacs. Best is

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bigglm on your big data set in open source R, it just works – similar as in SAS

bigglm on your big data set in open source R, it just works – similar as in SAS

In a recent post by Revolution Analytics (link & link) in which Revolution was benchmarking their closed source generalized linear model approach with SAS, Hadoop and open source R, they seemed to be pointing out that there is no 'easy' R open source solution which exists for building a poisson regression model on large datasets.    This post is about...

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Controlling heatmap colors with ggplot2

November 22, 2012
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Controlling heatmap colors with ggplot2

One of the most popular posts on this blog is the very first one, solving the issue of mapping certain ranges of values to particular colors in heatmaps. Given the abundance of ggplot2 usage in R plotting, I thought I’d … Continue reading →

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Creating an R package in Windows

November 21, 2012
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Creating an R package in Windows

A nice package can be both beautiful and functional. The image is CC by MIAD Communication Design. Inspired by Read more »

How to choose your next holidays destination – Uniform distribution on a sphere

November 14, 2012
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How to choose your next holidays destination – Uniform distribution on a sphere

If you want to choose randomly your next holidays destination, you are likely to process in a way which is certainly biased. Especially if you choose randomly the latitude and the longitude. A bit like they do in this lovely advertising (For those of y...

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Temporal networks with igraph and R (with 20 lines of code!)

November 10, 2012
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In my last post about how a twitter conversation unfolds in time on Twitter, the dynamical nature of information diffusion in twitter was illustrated with a video of the temporal network of interactions (RTs) between accounts. The temporal evolution of … Continue reading →   Related posts: Temporal network of information diffusion...

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Consuming R from SAP Mobile Platform

November 9, 2012
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Consuming R from SAP Mobile Platform

Early this year, in March, I was visiting my team mates in SAP Labs Palo Alto, and my good friend a team mate Rui Nogueira asked to participate in his most excellent Technology Innovation Podcast show where we spoke about R and SAP HANA. By the end of ...

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Terrain effects on SUHI estimates

November 9, 2012
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Terrain effects on SUHI estimates

Introduction Zhang and Imhoff (2010)  pdf here utilized NLCD impervious surface area (ISA), Olson biomes, and MODIS Land Surface temperature (LST) to estimate the magnitude of UHI in large cities across the US.  Peng  employed a   similar approach in studying 419 large cities ( population greater than 1m ) around world. Peng’s work suggests a limit or

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