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9b945cb2b4
* iterative and formula fibonacci methods Added two ways to calculate the fibonacci sequence: (1) iterative (2) formula. I've also added a timer decorator so someone can see the difference in computation time between these two methods. Added two unittests using the slash framework. * Update test_fibonacci.py * remove inline comments per Contributing Guidelines * Update sol5.py * Create placeholder.py * Update and rename maths/test_fibonacci.py to maths/tests/test_fibonacci.py * Delete placeholder.py * Create __init__.py * Update test_fibonacci.py * Rename Maths/lucasSeries.py to maths/lucasSeries.py * Update and rename Project Euler/Problem 01/sol5.py to project_euler/problem_01/sol6.py
121 lines
3.4 KiB
Python
121 lines
3.4 KiB
Python
# fibonacci.py
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"""
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1. Calculates the iterative fibonacci sequence
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2. Calculates the fibonacci sequence with a formula
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an = [ Phin - (phi)n ]/Sqrt[5]
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reference-->Su, Francis E., et al. "Fibonacci Number Formula." Math Fun Facts. <http://www.math.hmc.edu/funfacts>
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"""
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import math
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import functools
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import time
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from decimal import getcontext, Decimal
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getcontext().prec = 100
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def timer_decorator(func):
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@functools.wraps(func)
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def timer_wrapper(*args, **kwargs):
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start = time.time()
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func(*args, **kwargs)
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end = time.time()
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if int(end - start) > 0:
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print(f'Run time for {func.__name__}: {(end - start):0.2f}s')
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else:
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print(f'Run time for {func.__name__}: {(end - start)*1000:0.2f}ms')
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return func(*args, **kwargs)
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return timer_wrapper
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# define Python user-defined exceptions
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class Error(Exception):
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"""Base class for other exceptions"""
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class ValueTooLargeError(Error):
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"""Raised when the input value is too large"""
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class ValueTooSmallError(Error):
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"""Raised when the input value is not greater than one"""
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class ValueLessThanZero(Error):
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"""Raised when the input value is less than zero"""
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def _check_number_input(n, min_thresh, max_thresh=None):
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"""
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:param n: single integer
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:type n: int
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:param min_thresh: min threshold, single integer
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:type min_thresh: int
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:param max_thresh: max threshold, single integer
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:type max_thresh: int
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:return: boolean
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"""
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try:
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if n >= min_thresh and max_thresh is None:
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return True
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elif min_thresh <= n <= max_thresh:
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return True
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elif n < 0:
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raise ValueLessThanZero
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elif n < min_thresh:
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raise ValueTooSmallError
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elif n > max_thresh:
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raise ValueTooLargeError
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except ValueLessThanZero:
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print("Incorrect Input: number must not be less than 0")
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except ValueTooSmallError:
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print(f'Incorrect Input: input number must be > {min_thresh} for the recursive calculation')
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except ValueTooLargeError:
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print(f'Incorrect Input: input number must be < {max_thresh} for the recursive calculation')
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return False
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@timer_decorator
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def fib_iterative(n):
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"""
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:param n: calculate Fibonacci to the nth integer
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:type n:int
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:return: Fibonacci sequence as a list
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"""
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n = int(n)
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if _check_number_input(n, 2):
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seq_out = [0, 1]
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a, b = 0, 1
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for _ in range(n-len(seq_out)):
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a, b = b, a+b
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seq_out.append(b)
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return seq_out
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@timer_decorator
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def fib_formula(n):
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"""
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:param n: calculate Fibonacci to the nth integer
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:type n:int
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:return: Fibonacci sequence as a list
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"""
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seq_out = [0, 1]
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n = int(n)
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if _check_number_input(n, 2, 1000000):
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sqrt = Decimal(math.sqrt(5))
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phi_1 = Decimal(1 + sqrt) / Decimal(2)
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phi_2 = Decimal(1 - sqrt) / Decimal(2)
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for i in range(2, n):
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temp_out = ((phi_1**Decimal(i)) - (phi_2**Decimal(i))) * (Decimal(sqrt) ** Decimal(-1))
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seq_out.append(int(temp_out))
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return seq_out
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if __name__ == '__main__':
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num = 20
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# print(f'{fib_recursive(num)}\n')
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# print(f'{fib_iterative(num)}\n')
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# print(f'{fib_formula(num)}\n')
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fib_iterative(num)
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fib_formula(num)
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