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:

importmathv1=math.sin(10)# sinev2=math.cos(10)# cosinev3=math.tan(10)# tangent v4=math.asin(10)# arc sinev5=math.acos(10)# arc cosinev6=math.atan(10)# arc tangentv7=math.sinh(10)# hyperbolic sine v8=math.cosh(10)# hyperbolic cosinev9=math.tanh(10)# hyperbolic tangentvA=math.pow(2,4)# 2 raised to 4vB=math.exp(4)# e ^ 4vC=math.sqrt(10)# square rootvD=math.pow(5,1/3.0)# cubic root of 5vE=math.log(3)# ln; natural logarithmvF=math.log(100,10)# base 10vG=math.ceil(2.3)# ceilingvH=math.floor(2.7)# floorvI=math.pivJ=math.e

Example code using in-built operators

This code was made to replicate the log function in a calculator

importtimebase_number=input("[A]input base number: ")new_number=0result=input("[end number]input result ")exponent=0whileint(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:

importrandomv1=random.random()# Uniformly distributed random float >= 0.0 and < 1.0.v2=random.random()*10# Uniformly distributed random float >= 0.0 and < 10.0v3=random.randint(0,9)# Uniformly distributed random int >= 0 and <=9li=[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.

importdecimalplainFloat=1/3.0v1=plainFloat# 0.3333333333333333decFloat=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.

fromfractionsimportFractiononeThird=Fraction(1,3)floatOneThird=1/3.0v1=Fraction(0.25)# 1/4v2=Fraction(floatOneThird)# 6004799503160661/18014398509481984v3=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.

importstatisticsasstatsv1=stats.mean([1,2,3,100])# 26.5v2=stats.median([1,2,3,100])# 2.5v3=stats.mode([1,1,2,3])# 1v4=stats.pstdev([1,1,2,3])# 0.82915...; population standard deviationv5=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