django-pivot

django-pivot is a wrapper around numpy, pandas and django-pandas letting you easily manipulate pivot tables on your queryset.

Install

pip install django-pivot2

Modify your model(s) to use django_pandas.managers.DataFrameManager or django_pandas.managers.DataFrameQuerySet:

class LongTimeSeries(models.Model):
  date_ix = models.DateTimeField()
  series_name = models.CharField(max_length=100)
  value = models.FloatField()

  objects = DataFrameManager()

Usage

This app basicaly gives APIs to request a pivot table. Everything is not automatic and developer must always declare:

• The possible values
• The possible rows and columns

And for a end-user the API will ask

• Values
• Rows
• Columns
• Aggregation functions
• Applied function
• Format

As class-based view

A mixin is available to compose you own pivot. It has the following behavior: - Display a form to collect parameters of pivot table - Display pivot table as HTML if valid input is given - Download data as file with format given in form

Example:

from django_filters.views import FilterView
from django_pivot.views import PivotView
from myapp import models

class LongTimeSeriesPivotView(PivotView, FilterView):
    template_name = "pivot.html
    model = models.LongTimeSeries

    values_choices = ['date_ix', 'value']
    rows_choices = cols_choices = ['serie_name', 'date_ix', 'value']

PivotView is compatible with Django's ListView, django-filters' FilterView or any kind of view with the same behavior.

With graphene-django

Coming soon

With graphene-django-extras

Example of schema.py:

from graphene_django import DjangoObjectType
from django_pivot.contrib.graphene_django_extras import PivotField
from myapp import models

class LongTimeSeriesType(DjangoObjectType):
    class Meta:
        model = models.LongTimeSeries

class Query:
    pivot_long_time_series = PivotField(
        LongTimeSeriesType,
        filterset_class=filtersets.LongTimeSeriesFilter,
        values_choices=['date_ix', 'value'],
        rows_choices=['serie_name', 'date_ix', 'value'],
        cols_choices=['serie_name', 'date_ix', 'value'],
    )

Example of request:

query {
  pivot_long_time_series (values: ["value"], rows: ["serie_name"], cols: ["value"], aggfuncs: ["mean"])
}

As GraphQL is supposed to return JSON only and pandas JSON format is ..hum... weird, we convert pivot_table into CSV and after into a list of list, so fully compatible.

With Django REST Framework

Coming soon