Arithmetic is a branch of mathematics that consists of the study of numbers. In python, there are three main type of numbers:

(1) integer numbers

`>>> x = 2`

`>>> type(x)`

`<class 'int'>`

(2) real numbers (float)

`>>> x = 3.1415`

`>>> type(x)`

`<class 'float'>`

(3) complex numbers (complex)

`>>> z = 1+2j`

`>>> type(z)`

`<class 'complex'>`

An operator is a symbol, a letter or even a word, used to do an operation between two numbers. Let's see the arithmetic operators in python through several simple examples:

### Operator addition +

The addition of two integers gives an integer, example:

`>>> 3 + 2`

`5`

The addition of a float and an integer gives a float, example:

`>>> 2.1 + 3`

`5.1`

The addition of two floats give a float, example:

`>>> 4.3 + 2.1`

`6.4`

The addition of an integer and a complex number, gives a complex number example:

`>>> x = 2`

`>>> z = 1 + 2j`

`>>> x + z`

`(3+2j)`

The addition of two complex numbers gives a complex number, example:

`>>> z1 = 1 + 2j`

`>>> z2 = 2 + 5j`

`>>> z1 + z2`

`(3+7j)`

### Operator subtraction -

The subtraction of an integer from an integer, gives an integer example:

`>>> 3 - 2`

`1`

The subtraction of n integer from a float, gives a float example:

`>>> 2.1 - 3`

`-0.8999999999999999`

The subtraction of a float from a float, gives a float example:

`>>> 4.3 - 2.1`

`2.1999999999999997`

The subtraction of a integer number from a complex number, gives a complex number example:

`>>> z = 1 + 2j`

`>>> z - 1`

`2j`

The subtraction of a complex number from a complex number, gives a complex number example:

`>>> z1 = 1 + 2j`

`>>> z2 = 2 + 5j`

`>>> z1 - z2`

`(-1-3j)`

### Operator multiplication *

Si on multiplie deux entiers en python on obtient un entier, exemple:

`>>> 3 * 2`

`6`

Si on multiplie un réel et un enitier en python on obtient un réel, exemple:

`>>> 2.1 * 3`

`6.300000000000001`

Si on multiplie deux réels en python on obtient un réel, exemple:

`>>> 4.3 * 2.1`

`9.03`

Si on multiplie deux nombres complexes en python on obtient un complexe, exemple:

`>>> z1 = 1 + 2j`

`>>> z2 = 2 + 5j`

`>>> z1 * z2`

`(-8+9j)`

`>>>`

### Operator division /

To divide a number by another there is the / operator, example:

`>>> 4 / 2`

`2.0`

with two floats:

`>>> 7.0 / 3.2`

`2.1875`

with a complex number

`>>> z = 1 + 2j`

`>>> z / 2`

`(0.5+1j)`

with two complex numbers

`>>> z1 = 1 + 2j`

`>>> z2 = 2 + 3j`

`>>> z1 / z2`

`(0.6153846153846154+0.07692307692307691j)`

### Operator power **

To raise a number to the power of another number, there is the ** operator

`>>> 3**2`

`9`

since 3 * 3 = 8

`>>> 3**3`

`27`

since 3 * 3 * 3 = 27

with floats:

`>>> 7.0 / 3.2`

`2.1875`

with a complex number

`>>> z = 1 + 2j`

`>>> z ** 2`

`(-3+4j)`

with z1 ** z2

`>>> z1 = 1 + 2j`

`>>> z2 = 2 + 3j`

`>>> z1**z2`

`(-0.015132672422722659-0.179867483913335j)`

### Remainder of the Euclidean division

`>>> 5 % 3`

`2`

since 5 = 1 * 3 + 2

### Quotient of the Euclidean division

`>>> 5 // 3`

`1`

since 5 = 1 * 3 + 2

### References

Links | Site |
---|---|

Arithmétique | wikipedia |

Python Operator – Types of Operators in Python | data-flair.training |

Python Operators | w3schools.com |

operator — Standard operators as functions | docs.python.org |

Programmation Python/Opérateurs | wikibooks |

Euclidean division | wikipedia |

Python Operators Tutorial for Beginners to Learn | techbeamers.com |