OOP with mytime

[kxjakkk]

I'm trying to write a boolean function that takes two Mytime objects, t1 and t2 as arguments, and returns True if the object falls inbetween the two times.

This is a question from the How to Think Like a Computer Scientist book, and I need help.

What I've gotten so far:

class MyTime:
    def __init__(self, hrs=0, mins=0, secs=0):
        self.hours = hrs
        self.minutes = mins
        self.seconds = secs

def between(t1, t2):
    if t1 <= t2:
        return True
    else:
        return False

I just don't understand how to make a function that uses MyTime objects into the boolean function? Any help would be great.

[David W]

You might try something like this ...

# compareTimes.py #

class MyTime: # 24 hour clock #

    def __init__(self, hrs=0, mins=0, secs=0):
        self.hours = hrs
        self.minutes = mins
        self.seconds = secs
        # normalize ... #
        if self.seconds >= 60:
            self.minutes += self.seconds//60
            self.seconds = self.seconds % 60
        if self.minutes >= 60:
            self.hours += self.minutes//60
            self.minutes = self.minutes % 60
        if self.hours >= 24:
            self.hours = self.hours % 24

    def get_sec(self):
        return (self.hours*60 + self.minutes) * 60 + self.seconds

    def __str__(self):
        return '{:02d}:{:02d}:{:02d}'.\
               format( self.hours, self.minutes, self.seconds )


def between( t1, t, t2 ):
    return t1.get_sec() <= t.get_sec() <= t2.get_sec()


t1 = MyTime( 9, 59, 59 )
print( 't1 =', t1 )

t2 = MyTime( 10, 0, 1 )
print( 't2 =', t2 )

t = MyTime( 10, 0, 0 )
print( 't =', t )

print( 'between( t2, t, t1 ) =', between( t2, t, t1 ) )
print( 'between( t1, t, t2 ) =', between( t1, t, t2 ) )
print( 'between( t, t1, t2 ) =', between( t, t1, t2 ) )

print( 'between( t, t, t ) =', between( t, t, t ) )

[kxjakkk]

Just wondering, but shouldn't it be returning True when its between(t1, t, t2)? It currently returns False.

[David W]

Yes ... it is.

These are the program output results I get:
(# Note: comment added #)

t1 = 09:59:59
t2 = 10:00:01
t = 10:00:00
between( t2, t, t1 ) = False
between( t1, t, t2 ) = True # NOTE: True as expected #
between( t, t1, t2 ) = False
between( t, t, t ) = True

[David W]

Actually ... the notion of 'between' ...

could actually be expressed as this:

class MyTime: # 24 hour clock #

    def __init__(self, hrs=0, mins=0, secs=0):
        self.hours = hrs
        self.minutes = mins
        self.seconds = secs
        # normalize ... #
        if self.seconds >= 60:
            self.minutes += self.seconds//60
            self.seconds = self.seconds % 60
        if self.minutes >= 60:
            self.hours += self.minutes//60
            self.minutes = self.minutes % 60
        if self.hours >= 24:
            self.hours = self.hours % 24

    def get_sec(self):
        return (self.hours*60 + self.minutes) * 60 + self.seconds

    def __str__(self):
        return '{:02d}:{:02d}:{:02d}'.\
               format( self.hours, self.minutes, self.seconds )

    def between(self, t1, t2 ):
        return t1.get_sec() <= self.get_sec() <= t2.get_sec() \
               or t2.get_sec() <= self.get_sec() <= t1.get_sec()