Scale

The scale module contains the class Scale which implements generic scale behaviour. This class represents the conventional notion of a measurement scale (also commonly called a unit).

Different categories of scale are implemented as classes derived from Scale:

  • Instances of RatioScale scales have an absolute zero, like the metre scale for length or the kelvin scale for thermodynamic temperature.

  • IntervalScale scales are measurement scales with an arbitrary zero, like the Fahrenheit and Celsius temperature scales.

class IntervalScale(kind_of_quantity, name, symbol)

An IntervalScale has an arbitrary origin. Units associated with an interval scale may not be multiplied or divided.

static value_conversion_function()

Generic conversion function from one interval scale to another

class OrdinalScale(kind_of_quantity, name, symbol)
class RatioScale(kind_of_quantity, name, symbol, conversion_factor=None)

A RatioScale is a metric scale. Units may be multiplied and divided.

property conversion_factor

Return a conversion factor for a value on this scale to one on the reference scale

static value_conversion_function()

Generic conversion function from one ratio scale to another

class Scale(kind_of_quantity, name, symbol)

A Scale has a name (and a short name, or symbol) and contains a reference to the associated kind of quantity.