An implementation of an uncertainty-aware calculator in python. A dart version is available here
This module provides four classes, all derived from a general EquationComponent which represents a numerical value and its associated uncertainty.
- EquationValue, which represents a measured value.
- EquationBrackets, which essentially stands in for a bracket in a real mathematical formula, grouping equation components and applying an operator to them all. Available operations are: add, subtract, multiply, and divide.
- EquationPower, which represents an EquationComponent to the power of a positive integer value.
- EquationFunction, which allows the use of complex mathematical functions to be performed on its EquationComponent. It calculates uncertainty using the Brute Force method.
NOTE: Some modification may be required to account for differences in methodology.
A simple usage example, for calculating the mass of the energy converted from gravitational energy when a (10000000000000000 ± 10000000) kg mass is dropped (5 ± 0.1) metres.
Rearranging the equations: E = m_2 * c^2 and E = m_1 * g * h, gives: m_2 = (m_1 * g * h) / (c^2)
from decimal import Decimal as D
from uncertain_solver import *
# define values
m_1 = EquationValue.from_uncertainty_plus_minus(D("10000000000000000"), uncertainty_plus_minus=D("10000000"))
g = EquationValue(D('9.7988'), uncertainty_percentage=D("0.7")) # From: https://physics.stackexchange.com/a/93298
h = EquationValue.from_uncertainty_plus_minus(D('5'), uncertainty_plus_minus=D('0.1'))
c = EquationValue(D('299792458'), uncertainty_percentage=D('0'))
# Define equation
m_2 = EquationBrackets(
[
EquationBrackets([m_1, g, h], operator=EquationOperator.MULTIPLY),
EquationPower(c, power=2)
],
operator=EquationOperator.DIVIDE
)
print(m_2)For a complete demonstration, see example.py.