Computational biology and genomics
The only times I used backticks in R was when a file was imported into R and the column names had spaces (as a side note, please don’t use spaces in your column or file names but use an underscore, i.e. _). For example, you can access col a by using backticks. my_df <- data.frame(…
In this vectors and lists tutorial, the example code wraps the R vector assignments with parentheses or round brackets. (v_log <- c(TRUE, FALSE, FALSE, TRUE)) #> [1] TRUE FALSE FALSE TRUE (v_int <- 1:4) #> [1] 1 2 3 4 (v_doub <- 1:4 * 1.2) #> [1] 1.2 2.4 3.6 4.8 (v_char <- letters[1:4]) #>…
Two widely used file formats in bioinformatics, VCF and GTF, have single columns that are packed with annotation information. This makes them a bit inconvenient to work with in R when using data frames because the values need to be unpacked, i.e. split. In addition, this violates one of the conditions for tidy data, which…
In this post, I will describe a series of data processing steps in R that I often perform that involves the map_df, inner_join, and pivot_longer functions from the purrr, dplyr, and tidyr packages, respectively. They are all part of the tidyverse, so to follow this post, please install the tidyverse package. install.packages("tidyverse") library(tidyverse) The typical…
I have used BLAT to align full-length mRNA sequences a long time ago. Since BLAT has been out for over 20 years, I was wondering what modern day alignment tool I could use as a replacement. Minimap2 came to mind and in this post I use it to map some known transcript sequences to the…
In this post, I outline an approach for retrieving weather conditions from the command line. There are websites and widgets that provide weather details but I like using the command line because I find that it’s more efficient than pointing and clicking on stuff. In addition, this approach enables us to program specific tasks. For…
In this post, I describe a simple workflow for identifying Omicron variants from some sequencing data shared by the Kwazulu-Natal Research Innovation and Sequencing Platform (KRISP) and the Centre for Epidemic Response and Innovation (CERI). To follow the workflow, you need to have Docker installed and an Internet connection. To get started, run a container…
I was updating my BAM to CRAM post spurred on by a recent comment and then I wondered whether I could store my FASTQ files as unaligned CRAM files to save space. I thought it wouldn’t be possible because the reads are unaligned and therefore we can’t make use of a reference to save space…
In my last post I outlined an approach for automatically creating reproducible documentation using GitHub Actions. I have now updated my Docker documentation using the same approach but without using a container because then I’d have to run Docker inside a Docker container (which is actually possible using GitLab’s CI/CD platform but I haven’t tried…
I had previously written about my workflow for creating reproducible documentation for SAMtools. The main idea was to generate the documentation via a R Markdown document that includes the documentation and the SAMtools commands to be executed on the command line (I do not know of another tool that can achieve this but if you…