# -*- coding: utf-8 -*-
"""
GStools subpackage providing geometric tools.
.. currentmodule:: gstools.tools.geometric
The following functions are provided
.. autosummary::
r3d_x
r3d_y
r3d_z
pos2xyz
xyz2pos
"""
# pylint: disable=C0103
from __future__ import print_function, division, absolute_import
import numpy as np
__all__ = ["r3d_x", "r3d_y", "r3d_z", "pos2xyz", "xyz2pos"]
# Geometric functions #########################################################
[docs]def r3d_x(theta):
"""Rotation matrix about x axis.
Parameters
----------
theta : :class:`float`
Rotation angle
Returns
-------
:class:`numpy.ndarray`
Rotation matrix.
"""
sin = np.sin(theta)
cos = np.cos(theta)
return np.array(((1.0, +0.0, +0.0), (0.0, cos, -sin), (0.0, sin, cos)))
[docs]def r3d_y(theta):
"""Rotation matrix about y axis.
Parameters
----------
theta : :class:`float`
Rotation angle
Returns
-------
:class:`numpy.ndarray`
Rotation matrix.
"""
sin = np.sin(theta)
cos = np.cos(theta)
return np.array(((+cos, 0.0, sin), (+0.0, 1.0, +0.0), (-sin, 0.0, cos)))
[docs]def r3d_z(theta):
"""Rotation matrix about z axis.
Parameters
----------
theta : :class:`float`
Rotation angle
Returns
-------
:class:`numpy.ndarray`
Rotation matrix.
"""
sin = np.sin(theta)
cos = np.cos(theta)
return np.array(((cos, -sin, 0.0), (sin, +cos, 0.0), (+0.0, +0.0, 1.0)))
# conversion ##################################################################
[docs]def pos2xyz(pos, dtype=None, calc_dim=False, max_dim=3):
"""Convert postional arguments to x, y, z.
Parameters
----------
pos : :any:`iterable`
the position tuple, containing main direction and transversal
directions
dtype : data-type, optional
The desired data-type for the array.
If not given, then the type will be determined as the minimum type
required to hold the objects in the sequence. Default: None
calc_dim : :class:`bool`, optional
State if the dimension should be returned. Default: False
max_dim : :class:`int`, optional
Cut of information above the given dimension. Default: 3
Returns
-------
x : :class:`numpy.ndarray`
first components of position vectors
y : :class:`numpy.ndarray` or None
analog to x
z : :class:`numpy.ndarray` or None
analog to x
dim : :class:`int`, optional
dimension (only if calc_dim is True)
Notes
-----
If len(pos) > 3, everything after pos[2] will be ignored.
"""
if max_dim == 1: # sanity check
pos = np.array(pos, ndmin=2)
x = np.array(pos[0], dtype=dtype).reshape(-1)
dim = 1
y = z = None
if len(pos) > 1 and max_dim > 1:
dim = 2
y = np.array(pos[1], dtype=dtype).reshape(-1)
if len(pos) > 2 and max_dim > 2:
dim = 3
z = np.array(pos[2], dtype=dtype).reshape(-1)
if calc_dim:
return x, y, z, dim
return x, y, z
[docs]def xyz2pos(x, y=None, z=None, dtype=None, max_dim=3):
"""Convert x, y, z to postional arguments.
Parameters
----------
x : :class:`numpy.ndarray`
grid axis in x-direction if structured, or first components of
position vectors if unstructured
y : :class:`numpy.ndarray`, optional
analog to x
z : :class:`numpy.ndarray`, optional
analog to x
dtype : data-type, optional
The desired data-type for the array.
If not given, then the type will be determined as the minimum type
required to hold the objects in the sequence. Default: None
max_dim : :class:`int`, optional
Cut of information above the given dimension. Default: 3
Returns
-------
pos : :class:`numpy.ndarray`
the position tuple
"""
if y is None and z is not None:
raise ValueError("gstools.tools.xyz2pos: if z is given, y is needed!")
pos = []
pos.append(np.array(x, dtype=dtype).reshape(-1))
if y is not None and max_dim > 1:
pos.append(np.array(y, dtype=dtype).reshape(-1))
if z is not None and max_dim > 2:
pos.append(np.array(z, dtype=dtype).reshape(-1))
return tuple(pos)