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Class: Length

The Length class is a subclass of Variable designed to represent a one-dimensional quantity with unit-aware capabilities. It ensures accurate calculations by storing all values internally in its base unit, meters (m).

Supported Units

The following units are supported for initialization and conversion.

Unit str Conversion Factor to Meters (m)
meters m 1
centimeters cm 0.01
millimeters mm 0.001
inches in 0.0254
feet ft 0.3048
kilometers km 1000

Class Reference

class Length(value, units='m')

A class for handling length measurements with automatic unit conversion.

Parameters:

  • value : float or int
    The numeric value of the length. Must be a positive number.
  • units : str, default='m'
    The unit of the provided value. Must be one of the supported units.

Raises:

  • ValueError : If value is negative or units is not a valid unit.

Examples: 

# Create a Length object of 30 meters  
>>> length1 = Length(30)

# Create a Length object of 30 inches  
>>> length2 = Length(30, "in")

Properties

Property Type Description
.value float The numeric value of the length, always in meters (m). This is the internal representation used for all calculations.
.original_value float The numeric value as provided during initialization.
.original_unit str The unit as provided during initialization.

Methods

to(target_unit)

Returns a new Length object converted to the target_unit. The original object remains unchanged.

Parameters:

  • target_unit : str
    The unit to convert to. Must be one of the [supported units]

Returns:

  • Length
    A new Length object with the same value, represented in the target unit.

Raises:

  • ValueError : If target_unit is not a valid unit.

Examples: 

# Initialize a length of 5 meters  
>>> distance_m = Length(5)

# Convert to feet  
>>> distance_ft = distance_m.to("ft")

>>> print(distance_ft)  
16.4042 ft
Arithmetic Operations

The Length class supports addition (+) and comparison (==).

  • __add__(self, other)
    Adds two Length objects. The result is a new Length object with the unit of the first operand.
  • __eq__(self, other)
    Compares two Length objects for equality based on their internal meter values.

Examples: 

# Create two Length objects  
>>> length1 = Length(1, "m")  
>>> length2 = Length(10, "cm")

# Add them together  
>>> total_length = length1 + length2

>>> print(total_length)  
1.1 m
String Representation

  • __str__(self)
    Returns a human-readable string representation of the length, rounded to six decimal places, using its original value and unit.
  • __repr__(self)
    Returns an unambiguous string representation of the object.