In this blog post, I describe to ways to deal with code you do not want to run when it is sourced from an external file in R. When Python sources code it does a particular thing, it assigns the string ‘__main__’ to the __name__ variable in that code. However,… Read More »An R equivalent for Python’s if __name__ == ‘__main__’
Recently I had to read in a folder full of large Excel (.xlsx) files. I did as I usually did and use the xlsx library. However, reading in the largest files produced an error: “Error in .jcall(“RJavaTools”, “Ljava/lang/Object;”, “invokeMethod”, cl, : java.lang.OutOfMemoryError: Java heap space” I don’t know what cause… Read More »Error in .jcall(“RJavaTools”…) when importing large xlsx files in R
It happened too many times before I write this blog post. Oftentimes, when I read Excel (xls or xlsx) files into R, I encounter this strange phenomenon where dates are converted to a 5 number integer. Here is how to fix it. For example, 02/01/2017 (dd/MM/yyyy) would be converted to… Read More »Date conversion from Excel to R
Something that took me a while to do properly in ggplot2 is adding the percentage sign as a suffix to your tick labels, controlling decimals and at the same time still being able to set the limits of your axis. I’ll show an example using the iris data set. Let’s… Read More »Add percentages to your axes in R’s ggplot2 (and set the limits)
Although every statistics book will tell you not to go looking for statistical significance, sadly that’s still what happens in many analyses and scientific research. Often forgotten, is to check for statistical power. Here’s a refresher, and how to do it in R. Remember statistical significance? A finding is statistically… Read More »Statistical power, it matters. Even in R.
Als de leden van de partijen akkoord gaan, dan schiet de Vlaamse Regering woensdag uit de blokken. Het inburgeringsbeleid wordt strenger gemaakt: Jambon-I maakt het moeilijk, of quasi-onmogelijk, voor internationale migranten om aanspraak te kunnen doen op een sociale woning, de eerste tien jaar van hun verblijf in Vlaanderen. Daarmee… Read More »Met cijfers aan de slag om het succes van Vlaams Belang te verklaren
A two-sample t-test (aka an independent t-test or student’s t-test) is most often used to compare the means of two samples. For example: you might be checking if black cats, on average, have the same body weight as white cats. In this blog post I explain how to do a… Read More »The t-test in R revisited
Scientific notation can be handy if you want to save digits. However, if you need to present your results to the board, there’s gonna be that one guy who will ask what the ‘e’-thingy stands for. Here’s how you can make sure that your results are not returned in scientific… Read More »How to prevent scientific notation in R
In this blog post I tackle a problem for which I have been looking for an of-the-shelve solution: Converting the columns of a certain type of class to another class, while preserving the data frame. To this day I haven’t found it. That’s why I wrote this function. Let’s say… Read More »Applying as.factor (or numeric) to multiple columns in R
The following error message is something that me and my colleagues keep running into when using Rstudio. ‘Error Saving File — The device does not recognize the command’ There are multiple things that cause this, but basically it’s because RStudio is having troubles writing to the file. Here’s what you… Read More »Solve ‘The device does not recognize the command’ when saving a file in RStudio