April 18, 2019

Muller Report - Get your own PDF version here.

The Muller report. 

This is the redacted report, but if you want your own PDF file copy to read. Here it is. There are many other places to get it too but not all have a download. 

So click here to get a download from our share folder, click on this link:

Muller Report PDF file for downloading.

Or paste this address into your web browser.

https://drive.google.com/open?id=1O1bL-Es96WfQWs6Q-QtRBV6Ph9LomApP

Dr Mitton


April 4, 2019

Data Analysis Technical Special: Fixing Package Installation Problems for R and R-studio in OS-X.

What does this mean when I am trying to update R packages in R-Studio?

"xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun?
R-Studio is a popular workspace tool for getting started with R. I have been using R for some years to use the dose-response-curve (drc) package to fit our dose-response data. We study cells from human donor retinas, called endothelial cells. They form the inside of retinal blood vessels. Most new blindness in the United States each year is caused by diabetic retinopathy, which damages blood vessels. 


Wanting to update my own R-programming abilities and finding better ways to teach my own students and staff how to use R, I have been working through "Getting Started with R: An Introduction for Biologists" (2nd Edition, Beckerman, Childs, Petchey). The book makes the excellent point that the first problem in learning R for most students is getting stuck at how to get their data into R. It's not hard, but often the processes are explained poorly in many R-reference books. Unfortunately, while the authors have a good chapter on getting data into R, there is the reality that some of the functions and libraries needed to read in data from .cvs formatted files are in the R-package called readr. R-studio will ask you to let it install readr if it is missing in your library of packages and you can select YES, and Install, but sometimes the process fails. So as a new student of R, you get stuck at .... trying to get your data into R!! How do you fix this problem? Read on...