# -*- coding: utf-8 -*-
# -----------------------------------------------
# Filename: mopad_wrapper.py
# Purpose: Wrapper for mopad
# Author: Tobias Megies, Moritz Beyreuther
# Email: megies@geophysik.uni-muenchen.de
#
# Copyright (C) 2008-2012 ObsPy Development Team
# -----------------------------------------------
"""
ObsPy wrapper to the *Moment tensor Plotting and Decomposition tool* (MoPaD)
written by Lars Krieger and Sebastian Heimann.
.. seealso:: [Krieger2012]_
.. warning:: The MoPaD wrapper does not yet provide the full functionality of
MoPaD. Please consider using the command line script ``obspy-mopad`` for
now if you need the full power of MoPaD.
:copyright:
The ObsPy Development Team (devs@obspy.org)
:license:
GNU Lesser General Public License, Version 3
(https://www.gnu.org/copyleft/lesser.html)
"""
import numpy as np
from obspy.imaging.beachball import xy2patch
from obspy.imaging.scripts.mopad import BeachBall as mopad_BeachBall
from obspy.imaging.scripts.mopad import MomentTensor as mopad_MomentTensor
from obspy.imaging.scripts.mopad import epsilon
# seems the base system we (gmt) are using is called "USE" in mopad
KWARG_MAP = {
'size': ['plot_size', 'plot_aux_plot_size'],
'linewidth': ['plot_nodalline_width', 'plot_outerline_width'],
'facecolor': ['plot_tension_colour'],
'edgecolor': ['plot_outerline_colour'],
'bgcolor': [],
'alpha': ['plot_total_alpha'],
'width': [],
'outfile': ['plot_outfile'],
'format': ['plot_outfile_format'],
'nofill': ['plot_only_lines']
}
[docs]def _normalize_focmec(fm):
"""
Improve stability of plots by normalizing the moment tensors. The scale
does not matter for the beachballs.
"""
# Only normalize 6 component tensors.
if len(fm) != 6:
return fm
fm = np.array(fm, dtype=np.float64)
fm /= np.linalg.norm(fm)
return fm
[docs]def beach(fm, linewidth=2, facecolor='b', bgcolor='w', edgecolor='k',
alpha=1.0, xy=(0, 0), width=200, size=100, nofill=False,
zorder=100, mopad_basis='USE', axes=None):
"""
Return a beach ball as a collection which can be connected to an
current matplotlib axes instance (ax.add_collection). Based on MoPaD.
S1, D1, and R1, the strike, dip and rake of one of the focal planes, can
be vectors of multiple focal mechanisms.
:param fm: Focal mechanism that is either number of mechanisms (NM) by 3
(strike, dip, and rake) or NM x 6 (M11, M22, M33, M12, M13, M23 - the
six independent components of the moment tensor, where the coordinate
system is 1,2,3 = Up,South,East which equals r,theta,phi -
Harvard/Global CMT convention). The relation to Aki and Richards
x,y,z equals North,East,Down convention is as follows: Mrr=Mzz,
Mtt=Mxx, Mpp=Myy, Mrt=Mxz, Mrp=-Myz, Mtp=-Mxy.
The strike is of the first plane, clockwise relative to north.
The dip is of the first plane, defined clockwise and perpendicular to
strike, relative to horizontal such that 0 is horizontal and 90 is
vertical. The rake is of the first focal plane solution. 90 moves the
hanging wall up-dip (thrust), 0 moves it in the strike direction
(left-lateral), -90 moves it down-dip (normal), and 180 moves it
opposite to strike (right-lateral).
:param facecolor: Color to use for quadrants of tension; can be a string,
e.g. ``'r'``, ``'b'`` or three component color vector, [R G B].
Defaults to ``'b'`` (blue).
:param bgcolor: The background color. Defaults to ``'w'`` (white).
:param edgecolor: Color of the edges. Defaults to ``'k'`` (black).
:param alpha: The alpha level of the beach ball. Defaults to ``1.0``
(opaque).
:param xy: Origin position of the beach ball as tuple. Defaults to
``(0, 0)``.
:type width: int
:param width: Symbol size of beach ball. Defaults to ``200``.
:param size: Controls the number of interpolation points for the
curves. Minimum is automatically set to ``100``.
:param nofill: Do not fill the beach ball, but only plot the planes.
:param zorder: Set zorder. Artists with lower zorder values are drawn
first.
:param mopad_basis: The basis system. Defaults to ``'USE'``. See the
`Supported Basis Systems`_ section below for a full list of supported
systems.
:type axes: :class:`matplotlib.axes.Axes`
:param axes: Used to make beach balls circular on non-scaled axes. Also
maintains the aspect ratio when resizing the figure. Will not add
the returned collection to the axes instance.
.. rubric:: _`Supported Basis Systems`
========= =================== =============================================
Short Basis vectors Usage
========= =================== =============================================
``'NED'`` North, East, Down Jost and Herrmann 1989
``'USE'`` Up, South, East Global CMT Catalog, Larson et al. 2010
``'XYZ'`` East, North, Up General formulation, Jost and Herrmann 1989
``'RT'`` Radial, Transverse, psmeca (GMT), Wessel and Smith 1999
Tangential
``'NWU'`` North, West, Up Stein and Wysession 2003
========= =================== =============================================
"""
import matplotlib.collections as mpl_collections
from matplotlib import patches, transforms
fm = _normalize_focmec(fm)
# initialize beachball
mt = mopad_MomentTensor(fm, system=mopad_basis)
bb = mopad_BeachBall(mt, npoints=size)
bb._setup_BB(unit_circle=False)
# extract the coordinates and colors of the lines
radius = width / 2.0
neg_nodalline = bb._nodalline_negative_final_US
pos_nodalline = bb._nodalline_positive_final_US
tension_colour = facecolor
pressure_colour = bgcolor
if nofill:
tension_colour = 'none'
pressure_colour = 'none'
# based on mopads _setup_plot_US() function
# collect patches for the selection
coll = [None, None, None]
coll[0] = patches.Circle(xy, radius=radius)
coll[1] = xy2patch(neg_nodalline[0, :], neg_nodalline[1, :], radius, xy)
coll[2] = xy2patch(pos_nodalline[0, :], pos_nodalline[1, :], radius, xy)
# set the color of the three parts
fc = [None, None, None]
if bb._plot_clr_order > 0:
fc[0] = pressure_colour
fc[1] = tension_colour
fc[2] = tension_colour
if bb._plot_curve_in_curve != 0:
fc[0] = tension_colour
if bb._plot_curve_in_curve < 1:
fc[1] = pressure_colour
fc[2] = tension_colour
else:
coll = [coll[i] for i in (0, 2, 1)]
fc[1] = pressure_colour
fc[2] = tension_colour
else:
fc[0] = tension_colour
fc[1] = pressure_colour
fc[2] = pressure_colour
if bb._plot_curve_in_curve != 0:
fc[0] = pressure_colour
if bb._plot_curve_in_curve < 1:
fc[1] = tension_colour
fc[2] = pressure_colour
else:
coll = [coll[i] for i in (0, 2, 1)]
fc[1] = tension_colour
fc[2] = pressure_colour
if bb._pure_isotropic:
if abs(np.trace(bb._M)) > epsilon:
# use the circle as the most upper layer
coll = [coll[0]]
if bb._plot_clr_order < 0:
fc = [tension_colour]
else:
fc = [pressure_colour]
# transform the patches to a path collection and set
# the appropriate attributes
collection = mpl_collections.PatchCollection(coll, match_original=False)
collection.set_facecolors(fc)
# Use the given axes to maintain the aspect ratio of beachballs on figure
# resize.
if axes is not None:
# This is what holds the aspect ratio (but breaks the positioning)
collection.set_transform(transforms.IdentityTransform())
# Next is a dirty hack to fix the positioning:
# 1. Need to bring the all patches to the origin (0, 0).
for p in collection._paths:
p.vertices -= xy
# 2. Then use the offset property of the collection to position the
# patches
collection.set_offsets(xy)
collection._transOffset = axes.transData
collection.set_edgecolors(edgecolor)
collection.set_alpha(alpha)
collection.set_linewidth(linewidth)
collection.set_zorder(zorder)
return collection
[docs]def beachball(fm, linewidth=2, facecolor='b', bgcolor='w', edgecolor='k',
alpha=1.0, xy=(0, 0), width=200, size=100, nofill=False,
zorder=100, mopad_basis='USE', outfile=None, format=None,
fig=None):
"""
Draws a beach ball diagram of an earthquake focal mechanism. Based on
MoPaD.
S1, D1, and R1, the strike, dip and rake of one of the focal planes, can
be vectors of multiple focal mechanisms.
:param fm: Focal mechanism that is either number of mechanisms (NM) by 3
(strike, dip, and rake) or NM x 6 (M11, M22, M33, M12, M13, M23 - the
six independent components of the moment tensor, where the coordinate
system is 1,2,3 = Up,South,East which equals r,theta,phi). The strike
is of the first plane, clockwise relative to north.
The dip is of the first plane, defined clockwise and perpendicular to
strike, relative to horizontal such that 0 is horizontal and 90 is
vertical. The rake is of the first focal plane solution. 90 moves the
hanging wall up-dip (thrust), 0 moves it in the strike direction
(left-lateral), -90 moves it down-dip (normal), and 180 moves it
opposite to strike (right-lateral).
:param facecolor: Color to use for quadrants of tension; can be a string,
e.g. ``'r'``, ``'b'`` or three component color vector, [R G B].
Defaults to ``'b'`` (blue).
:param bgcolor: The background color. Defaults to ``'w'`` (white).
:param edgecolor: Color of the edges. Defaults to ``'k'`` (black).
:param alpha: The alpha level of the beach ball. Defaults to ``1.0``
(opaque).
:param xy: Origin position of the beach ball as tuple. Defaults to
``(0, 0)``.
:type width: int
:param width: Symbol size of beach ball. Defaults to ``200``.
:param size: Controls the number of interpolation points for the
curves. Minimum is automatically set to ``100``.
:param nofill: Do not fill the beach ball, but only plot the planes.
:param zorder: Set zorder. Artists with lower zorder values are drawn
first.
:param mopad_basis: The basis system. Defaults to ``'USE'``. See the
`Supported Basis Systems`_ section below for a full list of supported
systems.
:param outfile: Output file string. Also used to automatically
determine the output format. Supported file formats depend on your
matplotlib backend. Most backends support png, pdf, ps, eps and
svg. Defaults to ``None``.
:param format: Format of the graph picture. If no format is given the
outfile parameter will be used to try to automatically determine
the output format. If no format is found it defaults to png output.
If no outfile is specified but a format is, than a binary
imagestring will be returned.
Defaults to ``None``.
:param fig: Give an existing figure instance to plot into. New Figure if
set to ``None``.
.. rubric:: _`Supported Basis Systems`
========= =================== =============================================
Short Basis vectors Usage
========= =================== =============================================
``'NED'`` North, East, Down Jost and Herrmann 1989
``'USE'`` Up, South, East Global CMT Catalog, Larson et al. 2010
``'XYZ'`` East, North, Up General formulation, Jost and Herrmann 1989
``'RT'`` Radial, Transverse, psmeca (GMT), Wessel and Smith 1999
Tangential
``'NWU'`` North, West, Up Stein and Wysession 2003
========= =================== =============================================
.. rubric:: Examples
(1) Using basis system ``'NED'``.
>>> from obspy.imaging.mopad_wrapper import beachball
>>> mt = [1, 2, 3, -4, -5, -10]
>>> beachball(mt, mopad_basis='NED') #doctest: +SKIP
.. plot::
from obspy.imaging.mopad_wrapper import beachball
mt = [1, 2, 3, -4, -5, -10]
beachball(mt, mopad_basis='NED')
"""
fm = _normalize_focmec(fm)
mopad_kwargs = {}
loc = locals()
# map to kwargs used in mopad
for key in KWARG_MAP:
value = loc[key]
for mopad_key in KWARG_MAP[key]:
mopad_kwargs[mopad_key] = value
# convert from points to size in cm
for key in ['plot_aux_plot_size', 'plot_size']:
# 100.0 is matplotlib's default DPI for savefig
mopad_kwargs[key] = mopad_kwargs[key] / 100.0 * 2.54
# use nofill kwarg
mt = mopad_MomentTensor(fm, system=mopad_basis)
bb = mopad_BeachBall(mt, npoints=size)
# show plot in a window
if outfile is None:
bb.ploBB(mopad_kwargs)
# save plot to file
else:
# no format specified, parse it from outfile name
if mopad_kwargs['plot_outfile_format'] is None:
mopad_kwargs['plot_outfile_format'] = \
mopad_kwargs['plot_outfile'].split(".")[-1]
else:
# append file format if not already at end of outfile
if not mopad_kwargs['plot_outfile'].endswith(
mopad_kwargs['plot_outfile_format']):
mopad_kwargs['plot_outfile'] += "." + \
mopad_kwargs['plot_outfile_format']
bb.save_BB(mopad_kwargs)