Friday, May 08, 2015

Self learning update for May 2015

See my autodidact post for an introduction of what this is about.

04 May 2015: Took one week off to port my Java game to Android (50% of my time), hobby electronics (25% of my time) and German improvement (25% of my time). I started with Developing Android Apps course but made no progress due to technical difficulties:
  • Android Studio is painfully slow on my laptop, Samsung ATIV Book 9 Lite (NP905S3G). Specs: Windows 8.1, Quad Core 1GHz, 4GB RAM, 40GB free disk space.
  • When I tried to use the emulator, I got "ERROR: x86 emulation currently requires hardware acceleration". Tried to install Intel HAXM, got "Computer does not support Intel Virtualization Technology (VT-x)". Checked BIOS, VT-x was enabled. 
  • Plugged in my Nexus 10, Android Studio did not recognize it.
  • I don't know what else to do.
05 May 2015: Tried my luck again with Android Studio, still no progress. Started watching  Android Development for Beginners which explains MIT App Inventor 2.

06 May 2015: Started using KanbanFlow.
Android: Android Studio emulator still not working, still not recognizing Nexus 10. Tried to build unsigned apk, success! Realized that my laptop does not recognize my Nexus 10. Installed universal adb driver, disabled USB debugging on Nexus, success. Copied apk to Nexus via USB, install, success. I still cannot see my real Nexus 10 on Android Studio. I might need a better computer. Main source of video lectures: Android Studio Tutorial by Derek Banas.
German: Two practices on Duolingo (20XP)
Electronics: Managed to control a DC motor.

07 May 2015:
Android: Wrote an app that counts from 0 to 9 with 500ms delay. I first tried Thread (which is usual for desktop Java apps), but Nexus said "the application stopped". Then I used postDelayed and finally it worked. This means that my existing Java library knowledge is not of much use, I have to learn new libraries. My tiring workflow was (without any debugging capability):
  1. Work in 25 minute blocks.
  2. Build app (~2min the first time, ~30s afterwards)
  3. Copy apk_debug.apk to Nexus.
  4. On Nexus install apk_debug.apk.
  5. Run apk_debug.apk.
  6. Repeat until you get what you want. 
German: 20 XP
Electronics: Get data from two photoresistors, drive servo motor. Problem: Humming in servo motor, sounds like instability.
Book review: Started working on Capital.

08 May 2015:
Book review: Finished Capital. Total pomodoros: 5
German: 30 XP
Electronics: Investigate servo humming

Book: Capital in the Twenty-First Century

"Capital in the Twenty-First Century", Thomas Piketty

This is a 500+ pages book. The first 200 pages were full of very similar looking data and tables. It became interesting after page 200, and riveting after page 300. I like books that show how ignorant I am and this is definitely one of them.

Read it if the following questions are of interest to you:
  • What is the source of income inequality and how does it harm society?
  • How should the income from production be divided between labor and capital?
  • Why is it so difficult to tax the super rich and multinational corporations?
  • Is publicly available financial information enough to form a healthy opinion about financial matters?
Update, January 11th 2016: Paul Graham says that we should not attack inequality (which is an indirect effect), but directly poverty and the questionable ways of getting rich:

Tuesday, May 05, 2015


WinDirStat is a disk usage statistics viewer and cleanup tool for various versions of Microsoft Windows. I used it to clean up my laptop.