Posts Tagged ‘ Bioinformatics ’

Mapping BioStar users onto the world map

October 9, 2010
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Mapping BioStar users onto the world map

Neil is my new bioinformatics hero! (Sorry Pierre :)BioStar is a Q&A website for bioinformatics, just like the Blue Obelisk eXchange. Neil and Pierre have an ongoing struggle to gain the most karma, requiring Pierre to put in a formal complaint aga...

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BioStar users (of the world, unite)

October 9, 2010
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BioStar users (of the world, unite)

Egon writes: Can someone please plot the BioStar users on a Google Map? Sounds like a challenge. Let’s go. 1. Harvesting user IP addresses BioStar user profiles (here’s mine) include a location field. It’s free text and optional, which means that location is missing or inaccurate for many users. However, if you’re logged into BioStar

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Connecting to a MongoDB database from R using the C API for MongoDB

September 24, 2010
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Today, Neil posted an article titled" Connecting to a MongoDB database from R using Java". In the current post, I'll show how to use the C API for MongoDB to fetch some MongoDB data from R. The code will be somehow similar to my previous post "A stateful C function for R: parsing Fasta sequences".OK, First, let's...

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GEO database: curation lagging behind submission?

August 30, 2010
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GEO database: curation lagging behind submission?

I was reading an old post that describes GEOmetadb, a downloadable database containing metadata from the GEO database. We had a brief discussion in the comments about the growth in GSE records (user-submitted) versus GDS records (curated datasets) over time. Below, some quick and dirty R code to examine the issue, using the Bioconductor GEOmetadb

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Analysing the ISMB 2010 meeting using R

July 20, 2010
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Analysing the ISMB 2010 meeting using R

The colossus of bioinformatics meetings, ISMB, convened in Boston this year from July 9 – 13. As in recent years, the meeting was covered online at its website, FriendFeed and Twitter. I thought it would be fun to run a quick analysis of activity at the FriendFeed room using R. 1. Fetch the data We

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biomaRt and GenomeGraphs: a worked example

June 6, 2010
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biomaRt and GenomeGraphs: a worked example

As promised a few posts ago, another demonstration of the excellent biomaRt package, this time in conjunction with GenomeGraphs. Here’s what we’re going to do: Grab some public microarray data Normalise and get a list of the most differentially-expressed probesets Use biomaRt to fetch the genes associated with those probesets Plot the data using GenomeGraphs

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Top 10 Algorithms in Data Mining

April 23, 2010
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The authors here invited ACM KDD Innovation Award and IEEE ICDM Research Contributions Award winners to each nominate up to 10 best-known algorithms in data mining, including the algorithm name, justification for nomination, and a representative public...

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A stateful C function for R: parsing Fasta sequences

April 19, 2010
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In the following post, I'll create a C extension for R. This extension will iterate over all the FASTA sequences in a file and will return a pair(name,sequence) for each sequence, that is to say that I won't store all the sequences in memory.The C code...

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‘R’ = dna.translate("AGG") . A custom C function for R, My notebook.

March 26, 2010
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In the following post, I will show how I've implemented a custom C function for R. This C function will translate a DNA to a protein. I'm very new to 'R' so feel free to make any comment about the code.C codeThe data in 'R' are stored in an opaque stru...

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Quality trimming in R using ShortRead and Biostrings

March 3, 2010
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Quality trimming in R using ShortRead and Biostrings

I wrote an R function to do soft-trimming, right clipping FastQ reads based on quality.This function has the option of leaving out sequences trimmed to extinction and will do left-side fixed trimming as well.#softTrim#trim first position lower than min...

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