units-python 0.6.6

Package for automatically managing units when doing calculations in python.

UnitsPythonPackage

Python package built with focus on simplicity, ease of use & readability.

Check out SPECIAL_UNITS in python_units/constants.py if you are missing some constants.

If your unit is missing, open a PR with your constant, the appropriate prefix and SI-unit added.

Installation

Install with:

pip install units_python

If you have already installed this package, but want the latest version use:

pip install units_python --upgrade

How to use:

In these examples, we have a physics problem to solve.

We will solve it using python_units to keep track of our units:

Physics Example 1:

How many soccer balls (diameter of 22 cm) can fit inside a 5 x 5 x 2.7 meter room?

See the example code here

Physics Example 2:

A runner has been running 96 km in 8 hours.

1. What are their average page?
2. If the runner continues at this pace, how far will they go in 46.2 minutes?

See the example code here

Value Object parameters:

The v object parameters are:

• value: string of value and desired unit split by a space
• ten_exponent (optional): float of the ten_exponent i.e: 1.8 * 10 ** 8 m would be v("1.8 m", 8).

Relevant methods:

• .copy() -> Value Object: returns copy of value
• .round(digits) -> None: round value to number of digits (returns nothing)
• .sqrt(n=1) -> Value Object: takes n-squareroot of value (returns changed value)
• .raw_value() -> Float: returns the value of the object
• .unit.get() -> String: returns the unit
• .to(str) -> String: input string with desired unit: "km/h", "tons", "hours". Returns string with value and unit
• .change_unit(str) -> None: change unit of value to str e.g. if it was not done corectly
• .raw() -> Value Object: the string representation has ten exponents. This gives the value without any ten exponents.
• .abs() -> Value Object: returns new value object with the objects value being the absolute value

[See this for an example of how to use some of the functions]

Custom functions:

We supply certain relevant functions:

• sqrt(value, n=1): take n-squareroot of value

import units_python as up
from units_python import v

my_value = v("9 m^2")
my_value_sqrt = up.sqrt(my_value)
print(my_value_sqrt) # outputs "3 m"

• nsqrt(value, n): take n-squareroot of value

other_value = v("21 m^3")
my_value_3sqrt = up.nsqrt(my_value, 3)
print(my_value_sqrt) # outputs "3 m"

• round(value, digits): round value number

third_value = v("3.1415926535 m")
third_value_rounded = up.round(third_value, 4)
print(third_value_rounded) # outputs "3.1416 m"

What units can I use?

You can find all avaliable units in python_units.constant.UNITS & python_units.constant.SPECIAL_UNITS.

You can find all avaliable prefixes in python_units.constant.PREFIXES.

You can combine prefixes and units in whatever way you like. You can also combine multiple units: 'ton/liter', 'kg*liter/hour' etc.

What you, at this time, cannot do:

• exp
• value ** value (value ** constant works!)