Month: January 2015

Study Group: Algorithms & Data Structures

/ Daphne Chong / Leave a comment

Since doing a Javascript study group last year, I’ve been keen to organise a Data Structures & Algorithms study group (partly to brush up on interviewing).

I’m pleased to announce that the study group will start January 28th. If you’re interested and live in Sydney, read on.

What will I learn?

We will be doing the Algorithms I course by Princeton university.

It involves a series of lectures & quizzes you watch at home, followed by a group meeting every Wednesday. At the group meeting you can ask questions about anything you didn’t understand, and start to go through coding exercises.

The course material is presented in Java, however you can choose a language of your choice to complete the problems. If you would like Coursera to mark your assignments and final exam, you would need to complete the course in Java. (Note: Completion certificates aren’t issued for this course.)

If you are unsure of Java syntax, please read up on a quick syntax guide before starting the course.

Where and when do we meet?

Atlassian has kindly agreed to host our meetings. Their office is Level 6, 341 George Street Sydney. The building entrance is off Wynyard St.

We’ll meet on Wednesdays at 6:30pm (please be prompt).

The course is 6 weeks and runs from January 28th until March 4th. There will be an optional week after the course ends to practice answering technical interview questions.

How much will it cost?

The course is free if you attend 5 out of the 6 meetings. You can skip one meeting without a penalty.

Everyone will be asked to pay 6 x $10 per meeting at the first meeting, a total of $60. For every meeting you attend, you’ll be credited $10 back.

For anyone who misses a meeting, their money goes into a pot. At the end of the course, the pot will be divided among the people who attended the most meetings. Nerdery pays 🙂

This is mainly an attempt to identify the people who really want to participate, and to motivate people to stick with the group.

Prerequisites

This is not a beginner’s course. You should:

  • Be able to code confidently in a language of your choice
  • Be comfortable with git
  • Understand the concept of a class, objects, functions, arrays, lists, sets, loops, recursion and the core types available in your chosen language
  • Understand what unit testing is
  • Be willing to discuss your approaches to problems, and demo code
  • Be willing to spend 4-12 hours a week watching lectures and completing code assignments

I’m not teaching this content, I want to learn it and would like other motivated people around at the same time.

How can I sign up?

The study group will be limited to 15 people. The first 15 people who contact me (@daphnechong) and bring a refundable $60 to the first meeting will be eligible.

See you there 🙂

Hello, Arduino

/ Daphne Chong / Leave a comment

Last September, Women Who Code Sydney ran a Learn Arduino event. I’m generally not very keen on hardware, so I hadn’t bothered to investigate Arduino in depth, but this blinking green light from the workshop was one of the most exciting things I’d seen in ages. It was programming in physical form: I’d written the code, sent it to the motherboard, plugged in the wires and resistors to control the current, then seen something in my environment that I could actually touch and change.

IMG_7199

Arduino has been around for a while. It is a small version of a computer with very simple inputs and outputs, and that’s what makes them really fun to play with.  There are lots of different input sensors you can use, like temperature sensors, movement, infrared, light.

It’s fairly inexpensive to get a basic Arduino kit, as cheap as $30 depending on where you get it from. Atlassian kindly sponsored our event and donated 20 starter kits which included the basic Arduino board, and a whole lot of extra sensors to play with.

  • 1 x 830pt Breadboard
  • 4 x LED
  • 2 x RGB LED
  • 1 x 9V Plug
  • 1 x 9V Lead
  • 1 x Breadboard Power Module
  • 4 x Tactile Switch
  • 1 x Small Slide Switch
  • 10 x Resistors
  • 1 x pack of jumper wires
  • 1 x Light Dependant Resistor
  • 1 x Small Plastic Servo
  • 1 x Buzzer
  • 1 x Linear Rotary Potentiometer
  • 1 x Ultrasonic Sensor
  • 1 x Hall Effect Sensor
  • 1 x 7 Segment Display
  • 1 x Temperature sensor
  • 1 x IR phototransistor
  • 1 x NPN transistor BC547

Our host, Natalia Galin did a phenomenal job preparing for the event, even down to these cheat sheets with components separated out and nicely labelled, which made it easy to work on our tasks.

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First up was a crash-course on electronics, and how the Arduino’s breadboard circuitry works.

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Then a series of programming tasks to connect up the wiring so that lights work, and using physical switches to turn lights on and off. It was addictive!

We were limited by how many kits were available, but we had around 25 people attend the workshop, and the atmosphere was great. A huge thanks goes to Google for sponsoring the venue and catering for the night, and Atlassian for the Arduino kits.

IMG_7200

 

Astronomy courses at Sydney Observatory

/ Daphne Chong / Leave a comment

In November last year we finished our third course at Sydney Observatory run by Paul Payne – two on astronomy, and one on Einstein’s Theory of Relativity.

If you are interested in astronomy or relativity, they’re the perfect way to learn more in-depth concepts. My personal favourite was Astronomical Concepts, but we loved all of them! Paul is a great teacher, and explains a lot of complicated concepts in a clear and straightforward manner. He also teaches Java at TAFE, so he’s developed a set of computerised 3D models to go with his courses, which help enormously. The courses generally run along school terms, so that gives you plenty of time to sign up before the next one starts in February.

In our last night of the course, we spent a lot of time discussing the universe and its size. I’ll just leave this video of a universe fly-through right here, using data from the Sloan Digital Survey. Each one of those dots is a galaxy – there are over 400,000 of them featured in the video.

There is also a fantastic picture taken by the Hubble space telescope of a seemingly black corner of the sky, revealing thousands of galaxies that extend back in time to within a few million years of the big bang.  More information on the Hubble Ultra Deep Field image.

Hubble Ultra Deep Field image

Science is awesome.