How to get the minimum number that can be represented?

[Peng Yu]

Hi,

Suppose I want to define a function that return the minimum number
that can be represented.

def f(x):
  #body

That it, if I call f(10), f will return the minimum integer that can
be represented in the machine; if I cal f(10.5), f will return the
minimum float that can be represented in the machine.

Could somebody let me know what should be in the function body?

Regards,
Peng