django-mathfilters

django-mathfilters is a Python 3 module that provides different simple math filters for Django.

Django provides an add template filter, but no corresponding subtracting, multiplying or dividing filters.

Django ticket #361 has been closed as wontfix, so I had to create an alternative that is easy to install in a new Django project.

It currently supports int, float and Decimal types, or any other type that can be converted to int or float.

Installation

$ pip install django-mathfilters

Then add mathfilters to your INSTALLED_APPS.

Usage

You need to load mathfilters at the top of your template. The script provides the following filters:

• sub – subtraction
• mul – multiplication
• div – division
• intdiv – integer (floor) division
• abs – absolute value
• mod – modulo
• addition – replacement for the add filter with support for float / decimal types

Example:

{% load mathfilters %}

...

<h1>Basic math filters</h1>

<ul>
    <li>8 + 3 = {{ 8|add:3 }}</li>

    <li>13 - 17 = {{ 13|sub:17 }}</li>

    {% with answer=42 %}
    <li>42 * 0.5 = {{ answer|mul:0.5 }}</li>
    {% endwith %}

    {% with numerator=12 denominator=3 %}
    <li>12 / 3 = {{ numerator|div:denominator }}</li>
    {% endwith %}

    <li>|-13| = {{ -13|abs }}</li>
</ul>

Version Support

This module officially supports Python 3.5+ as well as PyPy3. Support for Python 3.3 and 3.4 is provided on best-effort basis, but there are no CI tests for it.

Supported Django versions are 1.11+, 2.x and 3.x.

Development

This project uses Black for auto-formatting. Adherence to the rules is enforced in CI.

License

MIT License, see LICENSE file.