Use floating point comparison
Add fixture recording script
Clean up whitespace
Join neighbouring loops
Join neighbouring loops; change of order needs new fixture
Factor initialisation as a function, with test
Replace boid count magic number with constant
Replace global variable access with function parameter
Replace magic number with constant
Replace magic numbers with constants
Replace magic number with constant
Replace repeated expression with variable
Replace repeated operation with temporary variable, order change, rerecord fixture
Refactor interaction into a function
Reparameterise so interaction is independent of count
Factor boids structure into a class
Separate boids class from animation code, into a module
Replace x,y,xv,yv arrays with a Boid class
Move interaction method into Boid class