Eliminate units when using quantities for Python

问题

I'm using the great quantities package for Python. I would like to know how I can get at just the numerical value of the quantity, without the unit.

I.e., if I have

E = 5.3*quantities.joule

I would like to get at just the 5.3. I know I can simply divide by the "undesired" unit, but hoping there was a better way to do this.

回答1:

E.item() seems to be what you want, if you want a Python float. E.magnitude, offered by tzaman, is a 0-dimensional NumPy array with the value, if you'd prefer that.

The documentation for quantities doesn't seem to have a very good API reference.

回答2:

I believe E.magnitude gets you what you want.

回答3:

>>> import quantities
>>> E=5.3*quantities.joule
>>> E.item()
5.3

来源：https://stackoverflow.com/questions/9403415/eliminate-units-when-using-quantities-for-python