Lottery number picker

Question

This is my first Python project. Let me know how I did, and where I can improve it.

# Random Lottery Number Pick Tool
# It has U.S. national lottos and two from Nebraska
# I'll add more to it later.

import random

# here is a giant body function I wonder if I could make this easier to deal with?
# it is basically my program's menu items.

def workerFunction():
    while True:
        try: x=input( '\n\n Select an option:\n\n'
                      'Press 1+Enter for Pick Three\n'
                      'Press 2+Enter for Pick Five\n'
                      'Press 3+Enter for Powerball picks\n'
                      'Press 4+Enter for Mega Millions picks\n'
                      'Q+Enter to quit \n\n'  )

        #This is my end of file logic that kills the program
        # Provided you pass Q + Enter

        except EOFError: pass
        if x.lower().startswith('q'):
            print("done")
            break

        # Otherwise you are passing something else that requires work from my factory!

        elif x == '1': print( '\n\n Nebraska Pick Three',
                              factory.repeater( 3, factory.factoryLogic, [0, 9, 1] ) )
        elif x == '2': print( '\n\n Nebraska Pick Five',
                              factory.factoryLogic( 1, 38, 5 ) )
        elif x == '3': print( '\n\n Powerball',
                              factory.factoryLogic( 1, 55, 5 ),
                              factory.factoryLogic( 1, 42, 1 ) )
        elif x == '4': print( '\n\n Mega Millions',
                              factory.factoryLogic( 1, 75, 5 ),
                              factory.factoryLogic( 1, 15, 1 ) )

# My factory class (self is set to something)...
# Not sure how to use it yet outside of the program I know it is like "this" in javascript.

class factory:

    # so I am defined self which looks like a struct. I assign it 0 (to shut up the syntax checker)

    def __init__( self ): self.a = 0

    # My logic module picks numbers based on a start and end position.
    # Not sure why I use +1 in the range function.
    # And then there are the number of interators I need.

    def factoryLogic( startPosi, endPosi, interateNumber ):
        a = random.sample( range( startPosi, endPosi+1 ), interateNumber )
        a.sort()
        return a

    # This is a repeater utility I made because pick three needs to be called three times.
    # The neat thing is that I am als passing a functions and args as a list and breaking them out.
    # I could make it more terse but why? It also returns an appended list. Neat!

    def repeater( times, f, functionArgs ):
        return_list = []
        for i in range( times ): return_list.append( f( functionArgs[0], functionArgs[1], functionArgs[2]  ) )
        return return_list

# This name main holds my worker function. I call it workerFunction! Amazing, yes?
if __name__ == '__main__':
    workerFunction()

Answer 1

You are not compliant with the style guide. For example:

• x and a aren't good variable names;
• You don't follow the naming convention (e.g. factory should be Factory and workerFunction should be worker_function);
• The inline comments should be replaced with docstrings;
• Extraneous whitespace (e.g. for i in range( times ): should be for i in range(times):); and
• Compound statements (e.g. except EOFError: pass should be on two lines).

---

The Pythonic replacement for lots of elif clauses is a dictionary. There are numerous ways to implement this, e.g.:

lotteries = {1: {'name': 'Nebraska Pick Three',
                 'func': factory.repeater
                 'args': (3, factory.factoryLogic, [0, 9, 1])},
             ...}

This simplifies the printout at the start:

print("Make a choice: ")
for key in sorted(lotteries):
    print("{0}. {1}".format(key, lotteries[key][name]))

and input validation:

if int(x) not in lotteries:

and the output:

lottery = lotteries[x]
print lottery['func'](*lottery['args'])

---

If you do want to stick with the current text block, Python does have multiline strings:

s = """Three quote marks
       makes a string
       multiline."""

For help on formatting, see Avoiding Python multiline string indentation.

---

The class implementation seems pointless - you have an __init__ that does very little (self.a is never referenced again), and two instance methods that don't need any class or instance attributes. If you want an OOP approach, I would be tempted by something like:

class Lottery:

    def __init__(self, rules):
        self.rules = rules

    def draw(self):
        ...

You can then put instances into the dictionary:

lotteries = {1: {'name': 'Nebraska Pick Three',
                 'lottery': Lottery(...)},
             ...}

and the code gets even simpler:

lottery = lotteries[x]['lottery']
lottery.draw()

You will have to come up with a method for representing the different rules. I would suggest having a Boolean for when repeat draws are allowed, rather than a sample, instead of calling a separate method as you do now. Different lotteries could alternatively be subclasses, rather than instances, of Lottery.

---

Here's an example implementation (note: for Python 3.x):

import random

class Lottery:
    """Simulate a specified lottery."""

    def __init__(self, name, rules):
        """Define the lottery name and draw rules."""
        self.name = name
        self.rules = rules

    def draw(self):
        """Simulate a single draw of the lottery."""
        output = []
        for rule in self.rules:
            output.extend(self._draw_rule(rule))
        return output

    def _draw_rule(self, rule):
        """Helper function to draw a single rule."""
        if rule.get('repeats', False):
            output = [random.randint(rule.get('min', 1), rule['max'])
                      for _ in range(rule.get('picks', 1))]
        else:
            output = random.sample(range(rule.get('min', 1), rule['max']+1),
                                   rule.get('picks', 1))
        return output


lotteries = {1: Lottery('Nebraska Pick Three',
                        [{'picks': 3, 'max': 9, 'repeats': True}]),
             2: Lottery('Nebraska Pick Five',
                        [{'picks': 5, 'max': 38}]),
             3: Lottery('Powerball',
                        [{'picks': 5, 'max': 75}, {'max': 15}])}

def play():
    """Allow the user to choose a lottery and simulate a draw."""
    print("Select a lottery:")
    for key in sorted(lotteries):
        print("{0}: {1.name}".format(key, lotteries[key]))
    while True:
        try:
            choice = int(input("Make a choice: "))
        except ValueError:
            print("Please enter an integer.")
        else:
            if choice in lotteries:
                break
            print("Not a valid choice.")
    print(lotteries[choice].draw())

if __name__ == "__main__":
    play()

And its output:

>>> play()
Select a lottery:
1: Nebraska Pick Three
2: Nebraska Pick Five
3: Powerball
Make a choice: foo
Please enter an integer.
Make a choice: 42
Not a valid choice.
Make a choice: 1
[1, 7, 9]
>>> play()
Select a lottery:
1: Nebraska Pick Three
2: Nebraska Pick Five
3: Powerball
Make a choice: 2
[34, 33, 20, 7, 35]
>>> play()
Select a lottery:
1: Nebraska Pick Three
2: Nebraska Pick Five
3: Powerball
Make a choice: 3
[75, 4, 12, 31, 55, 2]

Here I have used a simple dictionary implementation of the rules, with sensible defaults to minimise the input needed.