# How to do basic mathematical computations (in Python)

## Task

How do we write the most common mathematical operations in a given piece of software? For example, how do we write multiplication, or exponentiation, or logarithms, in Python vs. R vs. Excel, and so on?

## Solution

For those expressions that need the Python math package, use the code
`import math`

beforehand to ensure that package is loaded. Alternatively,
you can write `from math import *`

and thus drop the `math`

prefixes in
the table below.

Mathematical notation | Python code | Requires math package? |
---|---|---|

$x+y$ | `x+y` |
no |

$x-y$ | `x-y` |
no |

$xy$ | `x*y` |
no |

$\frac xy$ | `x/y` |
no |

$\left\lfloor\frac xy\right\rfloor$ | `x//y` |
no |

remainder of $x\div y$ | `x%y` |
no |

$x^y$ | `x**y` |
no |

$\vert x\vert$ | `abs(x)` |
no |

$\ln x$ | `math.log(x)` |
yes |

$\log_a b$ | `math.log(b,a)` |
yes |

$e^x$ | `math.exp(x)` |
yes |

$\pi$ | `math.pi` |
yes |

$\sin x$ | `math.sin(x)` |
yes |

$\sin^{-1} x$ | `math.asin(x)` |
yes |

$\sqrt x$ | `x**0.5` |
no |

$\sqrt x$ | `math.sqrt(x)` |
yes |

Other trigonometric functions are also available besides just `math.sin`

,
including `math.cos`

, `math.tan`

, etc.

Content last modified on 24 July 2023.

See a problem? Tell us or edit the source.

Contributed by Nathan Carter (ncarter@bentley.edu)