Package diffpy :: Package Structure :: Module lattice

Module lattice

class Lattice stores properites and provides simple operations in lattice
coordinate system.

Module variables:
    cartesian   -- constant instance of Lattice, default Cartesian system

Classes

[hide private]

Lattice
Lattice --> general coordinate system Data members: a, b, c, alpha, beta, gamma -- read-only lattice parameters, unit cell angles are in degrees.

Functions

[hide private]

cosd(x)
Return the cosine of x (measured in degrees).

source code

sind(x)
Return the sine of x (measured in degrees).

source code

Variables

[hide private]

__id__ = '$Id: lattice.py 2825 2009-03-09 04:33:12Z juhas $'

_EXACT_COSD = {0.0: 1.0, 60.0: 0.5, 90.0: 0.0, 120.0: -0.5, 18...

cartesian = Lattice()

Function Details

[hide private]

cosd(x)

source code

Return the cosine of x (measured in degrees).
Avoid round-off errors for exact cosine values.

sind(x)

source code

Return the sine of x (measured in degrees).
Avoid round-off errors for exact sine values.

Variables Details

[hide private]

_EXACT_COSD

Value:

{0.0: 1.0,
 60.0: 0.5,
 90.0: 0.0,
 120.0: -0.5,
 180.0: -1.0,
 240.0: -0.5,
 270.0: 0.0,
 300.0: 0.5}