Matrix to adjacency list in R

An adjacency list is simply an unordered list that describes connections between vertices. It's a commonly used input format for graphs. In this post, I use the melt() function from the reshape2 package to create an adjacency list from a correlation matrix. I use the geneData dataset, which consists of real but anonymised microarray expression data, from the Biobase package as an example. Finally, I'll show some features of the igraph package.

Continue reading

Intersect in R

A colleague asked me this question: "I'm trying to find a way to find genes that overlap between three datasets. I have used intersect for two dataframes but can't seem to find a solution for three dataframes on google. Do you know any snazzy way of doing that?" I thought using the venn() function from the gplots package is a pretty snazzy solution, so that's what I recommended.

Continue reading

Basic Shiny app to fetch variant information

I created a basic Shiny app that uses the myvariant package to fetch variant information from MyVariant.info. The variants need to be represented in the format recommended by the Human Genome Variation Society. Once you have your variant of interest in the correct format, just hit "Get variant info!" and the annotations will appear on the right. You can find the app hosted at: https://davetang.shinyapps.io/get_variant_info/.

Continue reading