Populations.py

#!/usr/bin/env python3

import argparse
from pickle import load, dump

class PopulationInfo:
    def __init__ (self, size, avgAge, femRatio):
        self.AVG_DEATH_AGE = 89.4
        self.size = size
        self.avgAge = avgAge
        self.femRatio = femRatio

def create(args):
    print("Creating a population of {}, average age of {} years, {}% of which is female.".format(args.size, args.avg_age, (args.fraction_female * 100)))
    new_pop = PopulationInfo(args.size, args.avg_age, args.fraction_female)
    print("Saving to {}...".format(args.filename))
    with open(args.filename, "wb") as f:
        dump(new_pop, f)
    print("Done.")


def analyse(args):
    '''Prints out a paragraph in English that describes a population based on the
    PopulationInfo provided by pickle from file located at args.filename.

    Result on screen will be in the form of:
        This is a population of size NUMBER. The population is LIFESTAGE, and
        there is a SEX_BALANCE.

    Yeah, it's like Mad Libs.
    '''
    print("Loading a population from file {}".format(args.filename))
    pop = None
    with open(args.filename, "rb") as f:
        pop = load(f)

    description = "This is a population of size {}. The population is ".format(pop.size)

    if(pop.avgAge <= (pop.AVG_DEATH_AGE / 3)):
        description += "young"
    elif(pop.avgAge <= (pop.AVG_DEATH_AGE * (2/3))):
        description += "middle-aged"
    elif(pop.avgAge <= pop.AVG_DEATH_AGE):
        description += "old"
    else:
        description += "extremely old"

    description += ", and there is a "

    if(pop.femRatio <= 0.25):
        description += "significant dominance of males."
    elif(pop.femRatio <= 0.45):
        description += "dominance of males."
    elif(pop.femRatio < 0.5):
        description += "slight dominance of males."
    elif(pop.femRatio == 0.5):
        description += "balance of the sexes."
    elif(pop.femRatio > 0.5 and pop.femRatio <= 0.55):
        description += "slight dominance of females."
    elif(pop.femRatio <= 0.65):
        description += "dominance of females."
    else:
        description += "significant dominance of females."

    print(description)

if __name__ == "__main__":
    cmparse = argparse.ArgumentParser(description="Generate natural-language statements from population information structures.")
    actions = cmparse.add_subparsers()

    parser_create = actions.add_parser("create", help="Create a new PopulationInfo")
    parser_create.add_argument("size", type=int, help="Size of the new population")
    parser_create.add_argument("avg_age", type=float, help="Average age of the new population")
    parser_create.add_argument("fraction_female", type=float, help="Fraction of the population that is female")
    parser_create.add_argument("filename", help="Pickled PopulationInfo to use")
    parser_create.set_defaults(func=create)

    parser_analyse = actions.add_parser("analyse", help="Analyse an existing PopulationInfo")
    parser_analyse.add_argument("filename", help="Pickled PopulationInfo to use")
    parser_analyse.set_defaults(func=analyse)

    args = cmparse.parse_args()
    args.func(args)