The Structure of a Program

Ven Popov

Previously on…

Recap

Week 1:

Why Programming? Course philosophy and the essence of computation

Week 2:

Computational Thinking & Basic R Operations

Short exercise: discuss core concepts for 5 minutes

How did the pi assignment go?

1. Programming as Problem-solving
2. The Two Essential components - data and functions
3. The process of

Today

The Big Picture	What is a program and how do we structure it?
The Building Blocks	Data versus Functions
The Environment	Where do names live and who can access them?
The Blueprint	Code organization & the terminal1
The Process	How do we put all this together?
Logistics	Discuss feedback and overview of the rest of the course

• you dipped your toes into telling a computer how to do something
• a traditional course might continue with specific tools
• we will look at the whole process of building software
• by software I mean everything - from a small script to a large application

1. Did not have time for, we’ll come back to this

Today (in a nutshell)

Anything worth doing is worth doing well

What is your first memory of interacting with a computer?

What is a program and how do we structure it?

What is our goal?

• Programming is about solving-problems
  • analyze data
  • create a simulation
  • create a tablet app for an experiment
  • build predictive models
• We solve problems by breaking them up into pieces
• Solve the pieces
• Put them together

What we want != what the computer “wants”

• it’s all about abstraction
• we package low-level instructions into meaningful functions
• functions can be named, reused, tested and documented
• ok, but what is a function?

Outlook: Rough list of topics to cover

• basic programming concepts
  • data structures
  • control statements - if, while, loops
  • functions
  • objects
  • scope
  • algorithms
  • randomness, seeds, distributions
  • tips & tricks
  • problem-solving

• filesystem, project organization & command line tools
• version control & collaboration
• dependency/environment management & cluster/cloud computing
• profiling, optimization and debugging
• testing, documentation & reporting
• (maybe: useful math refresher)