A Django application providing model and form field to accept and store multidimensional physical quantities.
This application depends on Pint
library, used for operate and manipulate physical quantities. Full documentation is available at http://pint.readthedocs.org/
Install django-quantity-field using pip: pip install django-quantity-field
.
In order to use a quantity field add it to your model definition:
from quantity_field import ureg
from quantity_field.fields import MultiQuantityField
class Package(models.Model):
size = MultiQuantityField(dim=3, units=(ureg.mm, ureg.cm, ureg.m))
weight = MultiQuantityField(units=(ureg.g, ureg.kg))
django-quantity-field
comes with the custom form field that is used by default for editing in admin or in your forms.
Accessing MultiQuantityField
field will returns MultiQuantity
object that can be used as ordinary Pint quantities.
>>> from quantity_field.base import MultiQuantity >>> size = MultiQuantity.from_list(2, 5.5, 4, str(ureg.m)) >>> size <Quantity(44.0, 'meter ** 3')> >>> size.dim 3 >>> [v for v in size] [<Quantity(2.0, 'meter')>, <Quantity(5.5, 'meter')>, <Quantity(4.0, 'meter')>]
Don't forget there are no global units in Pint. To use Pint quantities in your project side by side with django-quantity-field
use Pint registry from our application.
>>> from quantity_field import ureg >>> from quantity_field.base import MultiQuantity >>> box = MultiQuantity.from_string('42 kg') >>> box + 2.2 * ureg.kg <Quantity(44.2, 'kilogram')>