Add files via upload

cliffjsgit · web-flow · commit eb0e700c97b6 · 2020-04-30T01:07:17.000-05:00
diff --git a/time_class.py b/time_class.py
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+"""This module contains a code example related to
+
+Think Python, 2nd Edition
+by Allen Downey
+http://thinkpython2.com
+
+Copyright 2015 Allen Downey
+
+License: http://creativecommons.org/licenses/by/4.0/
+"""
+
+from __future__ import print_function, division
+
+
+class Time:
+    """Represents the time of day.
+
+    attributes: hour, minute, second
+    """
+    def __init__(self, hour=0, minute=0, second=0):
+        """Initializes a time object.
+
+        hour: int
+        minute: int
+        second: int or float
+        """
+        self.hour = hour
+        self.minute = minute
+        self.second = second
+
+    def __str__(self):
+        """Returns a string representation of the time."""
+        return '%.2d:%.2d:%.2d' % (self.hour, self.minute, self.second)
+
+    def print_time(self):
+        """Prints a string representation of the time."""
+        print(str(self))
+
+    def time_to_int(self):
+        """Computes the number of seconds since midnight."""
+        minutes = self.hour * 60 + self.minute
+        seconds = minutes * 60 + self.second
+        return seconds
+
+    def is_after(self, other):
+        """Returns True if t1 is after t2; false otherwise."""
+        return self.time_to_int() > other.time_to_int()
+
+    def __add__(self, other):
+        """Adds two Time objects or a Time object and a number.
+
+        other: Time object or number of seconds
+        """
+        if isinstance(other, Time):
+            return self.add_time(other)
+        else:
+            return self.increment(other)
+
+    def __radd__(self, other):
+        """Adds two Time objects or a Time object and a number."""
+        return self.__add__(other)
+
+    def add_time(self, other):
+        """Adds two time objects."""
+        assert self.is_valid() and other.is_valid()
+        seconds = self.time_to_int() + other.time_to_int()
+        return int_to_time(seconds)
+
+    def increment(self, seconds):
+        """Returns a new Time that is the sum of this time and seconds."""
+        seconds += self.time_to_int()
+        return int_to_time(seconds)
+
+    def is_valid(self):
+        """Checks whether a Time object satisfies the invariants."""
+        if self.hour < 0 or self.minute < 0 or self.second < 0:
+            return False
+        if self.minute >= 60 or self.second >= 60:
+            return False
+        return True
+
+
+def int_to_time(seconds):
+    """Makes a new Time object.
+
+    seconds: int seconds since midnight.
+    """
+    minutes, second = divmod(seconds, 60)
+    hour, minute = divmod(minutes, 60)
+    time = Time(hour, minute, second)
+    return time
+
+
+def main():
+    start = Time(9, 45, 00)
+    start.print_time()
+
+    end = start.increment(1337)
+    #end = start.increment(1337, 460)
+    end.print_time()
+
+    print('Is end after start?')
+    print(end.is_after(start))
+
+    print('Using __str__')
+    print(start, end)
+
+    start = Time(9, 45)
+    duration = Time(1, 35)
+    print(start + duration)
+    print(start + 1337)
+    print(1337 + start)
+
+    print('Example of polymorphism')
+    t1 = Time(7, 43)
+    t2 = Time(7, 41)
+    t3 = Time(7, 37)
+    total = sum([t1, t2, t3])
+    print(total)
+
+
+if __name__ == '__main__':
+    main()
