PyUnitWizard in your library
-Instructions to work with PyUnitWizard inside your own library-
Here you can find the instructions to include PyUnitWizard in your projects. Following this indications, you don’t need to worry about the requirements of the libraries supported by PyUnitWizard.
To illustrate how to include PyUnitWizard let’s see a very simple library you can find in github repository (examples directory): testlib. This is its structure:
tree --dirsfirst --charset=markdown testlib
testlib
|-- box
| |-- __init__.py
| |-- methods_a.py
| |-- methods_b.py
| `-- methods_c.py
|-- _pyunitwizard
| `-- __init__.py
|-- __init__.py
Make a directory named _pyunitwizard in your project top directory. And include in _pyunitwizard a __init__.py file such as:
### testlib/_pyunitwizard/__init__.py ###
import pyunitwizard as puw
# In this case Pint and openmm.unit are loaded
# and openmm.unit is defined as default form
puw.set_default_form('openmm.unit')
Now, let’s define some methods using your _pyunitwizard module. The first ones in the file main.py:
### testlib/main.py ###
from ._pyunitwizard import puw
def sum_quantities(a, b, form=None):
aa = puw.string_to_quantity(a, to_form=form)
bb = puw.string_to_quantity(b, to_form=form)
output = aa+bb
return output
def get_form(quantity):
return puw.get_form(quantity)
def libraries_loaded():
return puw.libraries_loaded()
And in a directory named box let’s include two methods to test your _pyunitwizard module:
### testlib/box/methods_a.py
from .._pyunitwizard import puw
def get_default_form():
return puw.get_default_form()
### testlib/box/methods_b.py
from .._pyunitwizard import puw
def set_default_form(form):
return puw.set_default_form(form)
Finnally, let’s writte the __init__.py files in the top directory and in box:
# testlib/box/__init__.py
from .methods_a import get_default_form
from .methods_b import set_default_form
# testlib/__init__.py
from .main import sum_quantities, get_form, libraries_loaded
from . import box
This way we already have a simple library using PyUnitWizard. You can check how testlib works:
In [1]: import testlib
In [2]: testlib.libraries_loaded()
Out[2]: ['pint', 'openmm.unit']
In [3]: q = testlib.sum_quantities('2cm','3cm')
In [4]: testlib.get_form(q)
Out[4]: 'openmm.unit'
In [5]: testlib.box.get_default_form()
Out[5]: 'openmm.unit'
In [6]: testlib.box.set_default_form('pint')
In [7]: q = testlib.sum_quantities('2cm','3cm')
In [8]: testlib.get_form(q)
Out[8]: 'pint'
