""" https://en.wikipedia.org/wiki/Taylor_series#Trigonometric_functions """ from math import factorial, pi def maclaurin_sin(theta: float, accuracy: int = 30) -> float: """ Finds the maclaurin approximation of sin :param theta: the angle to which sin is found :param accuracy: the degree of accuracy wanted minimum :return: the value of sine in radians >>> from math import isclose, sin >>> all(isclose(maclaurin_sin(x, 50), sin(x)) for x in range(-25, 25)) True >>> maclaurin_sin(10) -0.544021110889369 >>> maclaurin_sin(-10) 0.5440211108893703 >>> maclaurin_sin(10, 15) -0.5440211108893689 >>> maclaurin_sin(-10, 15) 0.5440211108893703 >>> maclaurin_sin("10") Traceback (most recent call last): ... ValueError: maclaurin_sin() requires either an int or float for theta >>> maclaurin_sin(10, -30) Traceback (most recent call last): ... ValueError: maclaurin_sin() requires a positive int for accuracy >>> maclaurin_sin(10, 30.5) Traceback (most recent call last): ... ValueError: maclaurin_sin() requires a positive int for accuracy >>> maclaurin_sin(10, "30") Traceback (most recent call last): ... ValueError: maclaurin_sin() requires a positive int for accuracy """ if not isinstance(theta, (int, float)): raise ValueError("maclaurin_sin() requires either an int or float for theta") if not isinstance(accuracy, int) or accuracy <= 0: raise ValueError("maclaurin_sin() requires a positive int for accuracy") theta = float(theta) div = theta // (2 * pi) theta -= 2 * div * pi return sum( (-1) ** r * theta ** (2 * r + 1) / factorial(2 * r + 1) for r in range(accuracy) ) def maclaurin_cos(theta: float, accuracy: int = 30) -> float: """ Finds the maclaurin approximation of cos :param theta: the angle to which cos is found :param accuracy: the degree of accuracy wanted :return: the value of cosine in radians >>> from math import isclose, cos >>> all(isclose(maclaurin_cos(x, 50), cos(x)) for x in range(-25, 25)) True >>> maclaurin_cos(5) 0.28366218546322675 >>> maclaurin_cos(-5) 0.2836621854632266 >>> maclaurin_cos(10, 15) -0.8390715290764525 >>> maclaurin_cos(-10, 15) -0.8390715290764521 >>> maclaurin_cos("10") Traceback (most recent call last): ... ValueError: maclaurin_cos() requires either an int or float for theta >>> maclaurin_cos(10, -30) Traceback (most recent call last): ... ValueError: maclaurin_cos() requires a positive int for accuracy >>> maclaurin_cos(10, 30.5) Traceback (most recent call last): ... ValueError: maclaurin_cos() requires a positive int for accuracy >>> maclaurin_cos(10, "30") Traceback (most recent call last): ... ValueError: maclaurin_cos() requires a positive int for accuracy """ if not isinstance(theta, (int, float)): raise ValueError("maclaurin_cos() requires either an int or float for theta") if not isinstance(accuracy, int) or accuracy <= 0: raise ValueError("maclaurin_cos() requires a positive int for accuracy") theta = float(theta) div = theta // (2 * pi) theta -= 2 * div * pi return sum((-1) ** r * theta ** (2 * r) / factorial(2 * r) for r in range(accuracy)) if __name__ == "__main__": import doctest doctest.testmod() print(maclaurin_sin(10)) print(maclaurin_sin(-10)) print(maclaurin_sin(10, 15)) print(maclaurin_sin(-10, 15)) print(maclaurin_cos(5)) print(maclaurin_cos(-5)) print(maclaurin_cos(10, 15)) print(maclaurin_cos(-10, 15))