The data module

The data module adds the MeasuredData class for working with values with uncertainty, add ands a number of helper functions to use with it.

Using MeasuredData

To create a MeasuredData object, you just need to provide a value and an error, like so:

from physics_utils import MeasuredData
# or, you could do
# from physics_utils.data import MeasuredData

# creates an object with a value of 7 and a
# reading error of 0.5
point = MeasuredData(7, 0.5)

print(point) # 7±0.5

Once you’ve created a MeasuredData object, you can treat it as any other numerical value, and perform whatever calculations you need to using it. The error will be automatically propagated as you do so.

from physics_utils import MeasuredData as MD

mu = MD(-0.00311, 0.00005)
m = MD(0.3057, 0.00005)
x = MD(0.242, 0.0002)

print(mu * 9.81 * m * x) # -0.00226±0.00004 

To use trigonometric functions with MeasuredData as the argument, you can use the built in .sine() .cosine() .tangent() .arcsin() and .arctan() methods on a MeasuredData object. Note that this will treat the MeasuredData as being in radians.

Averaging methods

The data module also provides methods for quickly averaging a bunch of measurements from the same device that have the same reading error, using the avg_from_set function; and for averaging a list of MeasuredData, using the avg_measured_datas function.