core/homeassistant/util/temperature.py

35 lines
1.2 KiB
Python

"""Temperature util functions."""
from homeassistant.const import (
TEMP_CELSIUS, TEMP_FAHRENHEIT, UNIT_NOT_RECOGNIZED_TEMPLATE, TEMPERATURE)
def fahrenheit_to_celsius(fahrenheit: float, interval: bool = False) -> float:
"""Convert a temperature in Fahrenheit to Celsius."""
if interval:
return fahrenheit / 1.8
return (fahrenheit - 32.0) / 1.8
def celsius_to_fahrenheit(celsius: float, interval: bool = False) -> float:
"""Convert a temperature in Celsius to Fahrenheit."""
if interval:
return celsius * 1.8
return celsius * 1.8 + 32.0
def convert(temperature: float, from_unit: str, to_unit: str,
interval: bool = False) -> float:
"""Convert a temperature from one unit to another."""
if from_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT):
raise ValueError(UNIT_NOT_RECOGNIZED_TEMPLATE.format(
from_unit, TEMPERATURE))
if to_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT):
raise ValueError(UNIT_NOT_RECOGNIZED_TEMPLATE.format(
to_unit, TEMPERATURE))
if from_unit == to_unit:
return temperature
elif from_unit == TEMP_CELSIUS:
return celsius_to_fahrenheit(temperature, interval)
return fahrenheit_to_celsius(temperature, interval)