PhysicalConstant

class sisl.constant.PhysicalConstant

Class to create a physical constant with unit-conversion capability, works exactly like a float.

To change the units simply call it like a method with the desired unit:

>>> m = PhysicalConstant(1., 'm')
>>> m.unit
'm'
>>> m2nm = m('nm')
>>> m2nm
1000000000.0 nm
>>> m2nm.unit
'nm'
>>> m2nm * 2
1000000000.0

Attributes

imag	the imaginary part of a complex number
real	the real part of a complex number
unit	Unit of constant

Methods

as_integer_ratio()	Return a pair of integers, whose ratio is exactly equal to the original float and with a positive denominator.
conjugate	Return self, the complex conjugate of any float.
fromhex(string)	Create a floating-point number from a hexadecimal string.
hex()	Return a hexadecimal representation of a floating-point number.
is_integer	Return True if the float is an integer.

as_integer_ratio() -> (int, int)

Return a pair of integers, whose ratio is exactly equal to the original float and with a positive denominator. Raise OverflowError on infinities and a ValueError on NaNs.

>>> (10.0).as_integer_ratio()
(10, 1)
>>> (0.0).as_integer_ratio()
(0, 1)
>>> (-.25).as_integer_ratio()
(-1, 4)

conjugate()

Return self, the complex conjugate of any float.

fromhex(string) → float

Create a floating-point number from a hexadecimal string. >>> float.fromhex(‘0x1.ffffp10’) 2047.984375 >>> float.fromhex(‘-0x1p-1074’) -5e-324

hex() → string

Return a hexadecimal representation of a floating-point number. >>> (-0.1).hex() ‘-0x1.999999999999ap-4’ >>> 3.14159.hex() ‘0x1.921f9f01b866ep+1’

imag

the imaginary part of a complex number

is_integer()

Return True if the float is an integer.

real

the real part of a complex number

unit

Unit of constant