vice.imf.salpeter
=================

The (unnormalized) Salpeter (1955) [1]_ stellar initial mass function
(IMF).

**Signature**: vice.imf.salpeter(mass)

.. versionadded:: 1.1.0

Parameters
----------
mass : real number
	The stellar mass in solar masses.

Returns
-------
dndm : real number
	The unnormalized value of the Salpeter IMF at that stellar mass,
	defined by:

	.. math:: \frac{dN}{dm} \propto m^{-\alpha}

	where :math:`\alpha` = 2.35 always.

Raises
------
* TypeError
	- mass is not a real number
* ValueError
	- mass is non-positive

Example Code
------------
>>> vice.imf.salpeter(1)
	1.0
>>> vice.imf.salpeter(0.5)
	5.098242509277049
>>> vice.imf.salpeter(2)
	0.19614602447418766

.. [1] Salpeter (1955), ApJ, 121, 161