The Adafruit PyPortal is a great device, with a few bells an whistles already integrated in order to start small electronic projects (but expensive, ok ;-)). As usual, Adafruit wrote a nice introductory guide. But some parts are outdated. Therefore, here are a few steps to get you started with CircuitPython on a PyPortal in 2021 …
A few words of appreciation for an open source software that can help you a lot in your work, Engauge Digitizer (ED) from Mark Mitchell. ED is a simple, straightforward curve digitizer: it takes images with graphs like the one below and transform them (with a little help) in data you can use later on.
Taking advantage of a trip to Canada and a very favourable CAN$:€ exchange rate, I bought a Dell XPS13 (9350 or “late 2015”), following excellent reviews from around the web. Dell sold a ’ developer edition’ of this laptop (shipping with Ubuntu Linux) but unfortunately it was out of stock on Dell US and I couldn’t find the item on the Dell Canada website. So I bought the Windows version with a touchscreen (it was Black Friday :-)). Here is how to install Fedora 23 on it (and probably most other Linux distribution) … I will focus on three aspects (in brief: everything works out of the box, except the wireless card that needed some additional action): How to boot and install Fedora Workstation What works and what doesn’t work out of the box Some things to do after installation (additional software)
I discover new things everyday … I wrote earlier that I really liked Zotero, a reference management software. However, there is one thing that was missing, imho: the capability to import PDFs (individually or in bulk) and correctly fill in the various fields of the reference. But in fact, this already exists in Zotero! Just drag a PDF in the middle section (the reference list) then right-click on it and choose “Retrieve Metadata from PDF” (*). Retrieval of the title, the authors, the journal, etc. everything goes very fast and they are stored as a normal reference, now on the right. ...
For my work I need to reference a lot of statements, mainly with papers and books in the biological / medical literature. Usually “professionals” use two proprietary software, Reference Manager or EndNote (both owned by Thomson Reuters). But there are a few very interesting free alternatives (see this comparison of reference management software). I switched from Mendeley to Zotero a few weeks ago and I’m very happy. Here is why …
Following my previous posts on how to read/write Excel files from Matlab here is the way I use to read/write Excel files from R. Again it seems the Apache POI java library made developers’life easy. I use here the simple-yet-powerful xlsx package ( documentation here in PDF; project website). Here you don’t need to install any additional files, installing the xlsx package from R does all the dirty work that for you. Then, reading an Excel file is very easy: ...
I was trying to reproduce the map of the GAVI Alliance eligible countries (btw I was surprised India is eligible - but that’s the beauty of relying on numbers only and not assumptions) in R. This is the original map (there are 57 countries eligible): I started to use the R package rworldmap because it seemed the most appropriate for this task. Everything went fine. Most of the time was spent converting the list of countries from plain English to plain “ISO3” code as required (ISO3 is in fact ISO 3166-1 alpha-3). I took my source from Wikipedia. ...
Well, there is nothing new in this statement. The smartphone OS Android is catching up and even overtaking its rival iOS in many domains: more activated products per day and per year in 2011, more Samsung Galaxy S3 (running Android) sold in Q3 2012 than iPhone4 and 5S (running iOS), more devices worldwide, catching up Apple’s market share in tablets, … All this is summarised in an infographics MBA Online designed (the original address is here: http://www.mbaonline.com/android/ - click at your own risk). It is sweet and colorful, with lots of numbers and some references in the end. Unfortunately these references are embedded in the image so you cannot click on them if you ever want to read more info. ...
If you are using Matlab on a MS-Windows PC with MS-Excel installed, there is no problem reading and writing data to Excel (in case your users/customers only understand this software but you still want to do the computations in Matlab). Here is the code to read (1st line) and write (2nd line): [sourcecode language=“matlab”] inputs = xlsread(‘inputfile.xls’, ‘inData’, ‘A1:B3’); [writeStatus, writeMsg] = xlswrite(‘outputfile.xls’, myMatrix, ‘outData’, ‘A1’); [/sourcecode] Now, there are several reasons why you may not be able to read and write directly to an Excel file: you have Matlab but ...
31% Tonight I was wondering what was Android market share in Asia. It is 31% according to a recent study from Ericsson’s ConsumerLab group ( reported by TechRepublic). Although dominant through most studied countries, Android is not dominant in Singapore (iOS has 46%), in Indonesia (RIM has 29%) nor in Vietnam (Symbian has 26%). Last year ABI Research released a study where they showed that Android-based smartphones market share grew from 16% in 2010 to 52% in 2011 (but this included tablets and did not cover exactly the same countries as the Ericsson study). Voila :-)