Python Programming/Math

For basic math including addition, subtraction, multiplication and the like, see ../Basic Math/ and ../Operators/ chapters. For quick reference, the built-in Python math operators include addition (+), subtraction (-), multiplication (*), division (/), floor division (//), modulo (%), and exponentiation (**). The built-in Python math functions include rounding (round()), absolute value (abs()), minimum (min()), maximum (max()), division with a remainder (divmod()), and exponentiation (pow()). Sign function can be created as "sign = lambda n: 1 if n > 0 else -1 if n < 0 else 0". Math A range of mathematical functions is available from math module of the standard library: import math v1 = math.sin(10) # sine v2 = math.cos(10) # cosine v3 = math.tan(10) # tangent v4 = math.asin(10) # arc sine v5 = math.acos(10) # arc cosine v6 = math.atan(10) # arc tangent v7 = math.sinh(10) # hyperbolic sine v8 = math.cosh(10) # hyperbolic cosine v9 = math.tanh(10) # hyperbolic tangent vA = math.pow(2, 4) # 2 raised to 4 vB = math.exp(4) # e ^ 4 vC = math.sqrt(10) # square root vD = math.pow(5, 1/3.0) # cubic root of 5 vE = math.log(3) # ln; natural logarithm vF = math.log(100, 10) # base 10 vG = math.ceil(2.3) # ceiling vH = math.floor(2.7) # floor vI = math.pi vJ = math.e Example code using in-built operators This code was made to replicate the log function in a calculatorimport time base_number = input("[A]input base number: ") new_number = 0 result = input("[end number]input result ") exponent = 0 while int(new_number) != int(result): exponent += float("0.0000001") new_number = int(base_number)**float(exponent) print(new_number) else: print("") print("The exponent or X is " + str(exponent)) time.sleep(200) Cmath The cmath module provides similar functions like the math module but for complex numbers, and then some. Random Pseudo-random generators are available from the random module: import random v1 = random.random() # Uniformly distributed random float >= 0.0 and < 1.0. v2 = random.random()*10 # Uniformly distributed random float >= 0.0 and < 10.0 v3 = random.randint(0,9) # Uniformly distributed random int >= 0 and <=9 li=[1, 2, 3]; random.shuffle(li); print(li) # Randomly shuffled list Decimal The decimal module enables decimal floating point arithmethic, avoiding certain artifacts of the usual underlying binary representation of floating point numbers that are unintuitive to humans. import decimal plainFloat = 1/3.0 v1 = plainFloat # 0.3333333333333333 decFloat = decimal.Decimal("0.33333333333333333333333333333333333333") v2 = decFloat # Decimal('0.33333333333333333333333333333333333333') decFloat2 = decimal.Decimal(plainFloat) v3 = decFloat2 # Decimal('0.333333333333333314829616256247390992939472198486328125') Fractions The fractions module provides fraction arithmetic via Fraction class. Compared to floating point numbers representing fractions, Fraction fractions do not lose precision. from fractions import Fraction oneThird = Fraction(1, 3) floatOneThird = 1/3.0 v1 = Fraction(0.25) # 1/4 v2 = Fraction(floatOneThird) # 6004799503160661/18014398509481984 v3 = Fraction(1, 3) * Fraction(2, 5) # 2/15 Statistics The statistics module, available since Python 3.4, provides some basic statistical functions. It only provides basics; it does not replace full-fledged 3rd party libraries such as numpy. For Python 2.7, the statistics module can be installed from pypi. import statistics as stats v1 = stats.mean([1, 2, 3, 100]) # 26.5 v2 = stats.median([1, 2, 3, 100]) # 2.5 v3 = stats.mode([1, 1, 2, 3]) # 1 v4 = stats.pstdev([1, 1, 2, 3]) # 0.82915...; population standard deviation v5 = stats.pvariance([1, 1, 2, 3]) # 0.6875; population variance External links 2. Built-in Functions, python.org 9. Numeric and Mathematical Modules, python.org 9.2. math — Mathematical functions, python.org 9.3. cmath — Mathematical functions for complex numbers, python.org 9.4. decimal — Decimal fixed point and floating point arithmetic, python.org 9.5. fractions — Rational numbers, python.org 9.6. random — Generate pseudo-random numbers, python.org 9.7. itertools — Functions creating iterators for efficient looping, python.org 9.7. statistics — Mathematical statistics functions, python.org