Thirteenth Class Notes

Announcements:

Github looking good (Merge @gerbal's pull request)
G+ check in
Thanks for the feedback - keep it coming
Local git installs, Jekyll, and site hacking oh my!
Guest Eric Martindale on Weds, so vim & emacs that day. See Emacs reading here
See exercise due Wednesday, below.

Installing `git`

Git is the open source version control program that underlies the Github collaboration website. We tried it last week, now we'll install and use it.

Installing git on Ubuntu is super easy. From a Terminal, type sudo apt-get install git

Some tutorials might tell you to install git-core, which will work too. To check whether git is installed, type which git which is a UNIX program that locates the location of the file that would be run if you typed a command. It's useful for checking if you have a program installed and, if so, where it is.

NEW: First- Time Setup

Git has an excellent first-time git setup turorial here. We did this during class and you should too if you're making up the work.

Cloning your first repo

Github does a pretty good job making it easy to clone repos. In the bottom right of every project page there is a box with the URL you'll need to clone. The syntax for cloning is git clone URL In the case of the turtlehack repo the URL is https://github.com/silshack/fall2013turtlehack.git. It's essentially the project's URL with a .git on the end.

Go ahead and clone turtlehack:

Open a terminal
Type git clone https://github.com/silshack/fall2013turtlehack.git
Type cd fall2013turtlehack to change directories into the folder git just created for you
Type ls to see what's in there.

Using a library

There's a file in the repo we cloned called turtlehack.py that has code we can use in it. We can access it in python by importing it.

Fire up python by typing python in a terminal.
from the >>> prompt type import turtlehack
you can then use custom functions by typing turtlehack.functionname(). For instance, after importing the turtlehack library, we could use the random_color() function by typing turtlehack.random_color()

Turtlehacking

So let's see what we can do! Type each line in sequence at a python prompt (>>>), then play around yourself.

import turtle
import turtlehack

roger = turtle.Turtle()

# draw a circle
roger.circle(20)

# random_color() returns a color value, so we put it where we'd normally put a color.
# you should see the 'turtle' chance colors at this point.
roger.color(random_color())

# draw another circle, slightly different in size, and see the different color!
roger.circle(30)

Contributing

random_color() is pretty sweet, but there are lots of improvements we can make to the Turtlehack project. Check out the Issues of the project to see what the organizer has identified as things that need improvement.

Exercise due Friday

By the end of Friday, particpate in the Turtlehack project in a meaningful way, and post a post showing how you've used the library to make a better Turtle drawing. Your post should have 1) a screenshot and 2) your code.

The SILShack class blog - Fall 2013