maths challenge practice

maths.py

#!/usr/local/bin/python

"""Ask complicated maths questions."""

__revision__ = 1

import sys

import random
import operator
import time
from math import log10
from datetime import datetime
from optparse import OptionParser


CORRECT_QUESTIONS = []
INCORRECT_QUESTIONS = []

def ask_question(maximum, operations, precision):
    """Ask a maths question and check the answer."""

    first_num = second_num = 0
    precision =  0 - precision
    
    while first_num == second_num:
        first_num = random.randint(0, maximum)
        first_num = round(first_num, precision)
        if first_num == 0:
            lower_limit = 1
        else:
            lower_limit = 0
        second_num = random.randint(lower_limit, maximum)
        second_num = round(second_num, precision)
    

    operation = random.choice(operations)
    if operation == "-" and (second_num > first_num):
        #avoid negative results for now
        (first_num, second_num) = (second_num, first_num)

    if operation == "-":
        answer = first_num - second_num
    else:
        answer = first_num + second_num

    start_time = datetime.now()
    while True:
        try:
            response = raw_input("%d %s %d = " % (first_num, operation, second_num))
            end_time = datetime.now()
            difference = end_time - start_time
            if int(response) == answer:
                CORRECT_QUESTIONS.append((first_num, operation, second_num, answer, difference))
                return True
            else:
                print "Incorrect; %d %s %d = %d" % (first_num, operation, second_num, answer)
                countdown("Learn from your mistake", 3, "and continue!")
                INCORRECT_QUESTIONS.append((first_num, operation, second_num, answer, response, difference))
                return False
        except ValueError:
            print "Invalid input, try again."


def interactive():
    """Ask user for parameters."""

    limit = raw_input("Enter highest number to use: ")
    limit = int(limit)
    if limit < 5:
        sys.exit("Choose a higher number!")
    operations = raw_input("Addition, subtraction, or both [asb]: ")
    if not operations in ("a", "s", "b"):
        sys.exit("Enter a, s or b!")
    if operations == "a":
        operations = ("+")
    elif operations == "s":
        operations = ("-")
    elif operations == "b":
        operations = ("+", "-")
    count = raw_input("Number of questions to ask (0 for infinite): ")
    count = int(count)
    precision = raw_input("Precision (i.e. number of digits to round to): ")
    precision = int(precision)
    run_quiz(limit, operations, count, precision)


def sensible_timedelta(timedelta):
    """Convert a timedelta into minutes and seconds."""
    minutes = timedelta.seconds / 60
    if minutes > 0:
        seconds = timedelta.seconds
        seconds -= (minutes * 60)
        return "%dmin %0.1fs" % (minutes, (seconds + (timedelta.microseconds / 1000000.0)))
    else:
        return "%0.1fs" % (timedelta.seconds + (timedelta.microseconds / 1000000.0))


def countdown(first_message, seconds, end_message):
    """Countdown until we start the quiz."""
    timer = seconds 
    print first_message,
    while timer > 0:
        print timer,
        sys.stdout.flush()
        time.sleep(1)
        timer -= 1
    print end_message + "\n" 


def run_quiz(limit, operations, count, precision):
    """Ask the right number of questions."""

    #sanity check
    if round(log10(limit)) < precision + 1:
        sys.exit("Error: precision cannot be higher than length of numbers in use, try %d" % (round(log10(limit)) - 1))

    total = 0
    correct = 0
    _count = count
    if count == 0:
        infinite = True
        print "Hit Ctrl-D to stop"
    else:
        infinite = False

    countdown("Get ready...", 5, "GO!")
    start_time = datetime.now()
    while count > 0 or infinite:
        try:
            total += 1
            if ask_question(limit, operations, precision):
                correct += 1
        except EOFError:
            total -= 1
            break
        count -= 1
    end_time = datetime.now()
    difference = end_time - start_time

    print "All done."
    option = raw_input("Display detailed results or summary [ds]: ")
    if option == "s":
        detailed = False
    else:
        detailed = True

    display_results(difference, _count, detailed)


def display_results(timetaken, count, detailed):
    """Output results and times."""
    if detailed:
        print
        if len(CORRECT_QUESTIONS) > 0:
            print "Correct answers:"
            correct_sorted = sorted(CORRECT_QUESTIONS, key=operator.itemgetter(4))
            for (first_num, operation, second_num, answer, difference) in correct_sorted:
                print "%2d %s %-2d = %-2d (%s)" % (first_num, operation, second_num, answer, sensible_timedelta(difference))
        if len(INCORRECT_QUESTIONS) > 0:
            print "Incorrect answers:"
            for ((first_num, operation, second_num, answer, response, difference)) in INCORRECT_QUESTIONS:
                print "%2d %s %-2d = %-2d [%2d]" % (first_num, operation, second_num, answer, int(response))
    print "\n%d correct out of %d questions (%d%%)." % (len(CORRECT_QUESTIONS), len(CORRECT_QUESTIONS) + len(INCORRECT_QUESTIONS), (len(CORRECT_QUESTIONS) / float(count) * 100))
    print "  Total time: %s" % (sensible_timedelta(timetaken))
    print "Average time: %0.1fs" % ((timetaken.seconds + (timetaken.microseconds / 1000000.0)) / float(count))


def main():
    """Figure out if we should ask for parameters and run quiz."""

    if len(sys.argv) == 1:
        interactive()
    else:
        parser = OptionParser()
        parser.set_defaults(ops="b", maximum="10", count="10", precision=0)
        parser.add_option("-m", "--max", dest="maximum", help="maximum value to use in question")
        parser.add_option("-c", "--count", dest="count", help="number of questions to ask (infinite if not given)")
        parser.add_option("-o", "--operations", dest="ops", help="question type; (a)ddition, (s)ubtraction, (b)oth", type="choice", choices=("a", "s", "b"))
        parser.add_option("-p", "--precision", dest="precision", help="precision: 1475 = 1000 (3), 1500 (2), 1480 (1), etc")

        (options, args) = parser.parse_args()
        if options.ops == "a":
            operations = ("+")
        elif options.ops == "s":
            operations = ("-")
        elif options.ops == "b":
            operations = ("+", "-")
        run_quiz(int(options.maximum), operations, int(options.count), int(options.precision))

if __name__ == "__main__":
    main()