Recent Posts

Functions Talk

I gave an introductory talk on making R functions

Cumsum and Diff Tricks

The idea Intervals One day (max) separation Wind Direction Fini There are many instances where you want to look for “trigger” events in a table (data frame) that mark the beginning of a sequence of records that need to be grouped together.

Inaugural Post

I have been keeping a file of solutions to small data analysis problems I find on the internet on my computer, and thought it might be nice to be able to point people at them… which kind of leads to having a blog.


  • California
Jeff Newmiller

Jeff Newmiller

Principal Engineer



Jeff Newmiller has been measuring, recording, and analyzing engineering data since 1986, and computing since 1981. While he took a detour into developing electronics and control software the aerospace industry in the early 1990s, most of his career has been focused on observing, characterizing and modeling photovoltaic power generation system performance.

These days, most of his time is spent consulting to the solar power generation industry and its investors on issues related to photovoltaic power production. The primary tools of his everyday work are R and Python.


  • Solar photovoltaic power
  • R statistical software


  • MS/BS in Mechanical Engineering, 1989/1986

    University of California, Davis