modelutil
Example: Atmospheric ConstantsThe AtmConst
class provides a comprehensive (someday)
and consistent definition of important atmospheric constants.
Constants are defined both
as class attributes and also as instance attributes
whose initial values are set by the class attribute version.
This "double-definition"
enables one to make local changes to local instances of the
AtmConst
class without having the changes propagate
to all subsequent references. At the same time, you can change the
value in all subsequent references, if you wish, by altering and
using the class attribute definition.
The AtmConst
class is found in the
atmconst
module in the package.
Here is an example of accessing the gas constant for dry air,
both as a class attribute and an instance attribute:
>>> from modelutil.atmconst import AtmConst
>>> AtmConst.R_d
287.05000000000001
>>> const = AtmConst()
>>> const.R_d
287.05000000000001
The pydoc documentation for the
AtmConst
class provides details as to what
constants are defined and their units, and also gives more
information about the difference in using the class and
instance attributes.