boundaryconditions.py

import math

class neumannCondition:
    def __call__(self, relativeTime):
        return 0

class velocityDirichletCondition:
    def __call__(self, relativeTime):
        finalVelocity = -5e-5
        if relativeTime <= 0.1:
            return finalVelocity * ( 1.0 - math.cos(relativeTime * math.pi / 0.1) ) / 2.0
        return finalVelocity

Functions = {
    'neumannCondition' : neumannCondition(),
    'velocityDirichletCondition' : velocityDirichletCondition()
}