Learning Tree International Blog

When R starts up, it looks for several files to initialize its configuration. R has its own configuration file called Rprofile.site located in the /etc folder. It is probably wise not to mess with this file unless you are very confident in your understanding. Most R users are aware that during startup, R reads an […]

Four years ago I wrote about the need to secure medical devices from potential attackers. The problem is still there and the potential for harm is just as great or greater. In October of this year (2018) the US Food And Drug Administration(FDA)’s Office of the Inspector General delivered a report entitled, THE FOOD AND […]

The Data Frame The fundamental data structure used by the majority of R functions and packages is the data frame. In a data frame, sets of related values constitute rows, while an individual column vector in a data frame contains comparable measures that can be summed, averaged, or subjected to any number of numerical manipulations. […]

“We’ve been watching your browsing and…” begins yet another ransomware email. The ones I receive allege that they have my password from a porn site (I’ve never visited one), they’ve compromised my router and seen the porn I watch (again, I don’t), and that they know the password for my email server (I’ve never used […]

In this blog I started explaining Learning Tree’s array of Linux training courses. I divided them into courses that prepare you for certification exams, versus those that teach you to use and manage the Linux environment. I explained the CompTIA, Microsoft, and Red Hat certification test-prep courses. Now let’s look at the courses that teach […]