Wrap meca

doc/api/index.rst

@@ -35,6 +35,7 @@ Plotting data and laying out the map:
  Figure.image
  Figure.shift_origin
  Figure.text
+ Figure.meca
 
 Color palette table generation:
 

pygmt/base_plotting.py

@@ -984,3 +984,153 @@ def text(
 
  arg_str = " ".join([fname, build_arg_string(kwargs)])
  lib.call_module("text", arg_str)
+
+ @fmt_docstring
+ @use_alias(R="region", J="projection", B="frame", S="convention")
+ @kwargs_to_strings(R="sequence",)
+ def meca(
+ self,
+ lon=None,
+ lat=None,
+ depth=None,
+ spec=None,
+ convention=None,
+ plot_lon=None, # FIXME: implement -C flag if plot location is specified
+ plot_lat=None,
+ text=None,
+ scale=None, # FIXME: implement
+ **kwargs,
+ ):
+ """
+ Plot focal mechanisms.
+
+ Parameters
+ ----------
+ lon: int or float
+ Longitude of event location.
+ lat: int or float
+ Latitude of event location.
+ depth: int or float
+ Depth of event location in kilometers.
+ spec: dict, 1D array, 2D array, or str
+ Object specifying event parameters that are consistent with the specified convention.
+ If a string specifying a filename is assigned to spec, no other parameters are required,
+ as those parameters are assumed to exist in the file.
+ List of required spec parameters for different conventions:
+ a (Aki & Rickards): strike, dip, rake, magnitude
+ c (global CMT): strike1, dip1, rake1, strike2, dip2, rake2, mantissa, exponent
+ m (seismic moment tensor): mrr, mtt, mff, mrt, mrf, mtf, exponent
+ p (partial focal mechanism): strike1, dip1, strike2, fault_type, magnitude
+ x (principal axis): t_exponent, t_azimuth, t_plunge, n_exponent, n_azimuth, n_plunge, p_exponent, p_azimuth, p_plunge, exponent
+ convention: str
+ a (Aki & Richards), c (global CMT), m (seismic moment tensor), p (partial focal mechanism), x (principal axis)
+ Optional (auto-detected) if spec is defined as a dict.
+ plot_lon: (optional) int or float
+ Longitude at which to place beachball
+ plot_lat: (optional) int or float
+ Latitude at which to place beachball
+ text: (optional) str
+ Text string to appear near the beachball
+
+ Examples
+ --------
+ fig = pygmt.Figure()
+ fig.meca(lon=239.384, lat=34.556, depth=12.0,
+ spec=dict(strike1=180, dip1=18, rake1=-88, strike2=0,
+ dip2=72, rake2=-90, mantissa=5.5, exponent=0),
+ region=[239, 240, 34, 35.2], projection='m4c')
+ fig.show()
+
+ fig = pygmt.Figure()
+ fig.meca(spec='focal_mechanisms.psmeca')
+ fig.show()
+ """
+
+ # Check the spec and parse the data according to the specified convention
+ if type(spec) is dict:
+ if lon is None or lat is None or depth is None: # if no specified location
+ raise GMTError("Location not fully specified.")
+
+ # These are constants related to GMT and could be defined elsewhere (top of file?)
+ AKI_PARAMS = ["strike", "dip", "rake", "magnitude"]
+ GCMT_PARAMS = [
+ "strike1",
+ "dip1",
+ "rake1",
+ "strike2",
+ "dip2",
+ "rake2",
+ "mantissa",
+ "exponent",
+ ]
+ # FIXME: allow specification of moment instead of mantissa and exponent.
+ MT_PARAMS = ["mrr", "mtt", "mff", "mrt", "mrf", "mtf", "exponent"]
+ PFM_PARAMS = ["strike1", "dip1", "strike2", "fault_type", "magnitude"]
+ PA_PARAMS = [
+ "t_exponent",
+ "t_azimuth",
+ "t_plunge",
+ "n_exponent",
+ "n_azimuth",
+ "n_plunge",
+ "p_exponent",
+ "p_azimuth",
+ "p_plunge",
+ "exponent",
+ ]
+
+ # Aki and Richards convention: -Sa in GMT
+ if set(spec.keys()) == set(AKI_PARAMS):
+ convention = "a"
+ foc_params = AKI_PARAMS
+
+ # Global CMT convention: -Sc in GMT
+ elif set(spec.keys()) == set(GCMT_PARAMS):
+ convention = "c"
+ foc_params = GCMT_PARAMS
+
+ # Seismic moment tensor convention: -Sm in GMT
+ elif set(spec.keys()) == set(MT_PARAMS):
+ convention = "m"
+ foc_params = MT_PARAMS
+
+ # Partial focal mechanism convention: -Sp in GMT
+ elif set(spec.keys()) == set(PFM_PARAMS):
+ convention = "p"
+ foc_params = PFM_PARAMS
+
+ # Principal axis convention: -Sx in GMT
+ elif set(spec.keys()) == set(PFM_PARAMS):
+ convention = "x"
+ foc_params = PA_PARAMS
+
+ else:
+ raise GMTError("Parameters in spec dict do not match known conventions.")
+
+ # Construct the vector (note that order matters here, hence the list comprehension!)
+ spec = [lon, lat, depth] + [spec[key] for key in foc_params]
+
+ # Add in plotting options, if given, otherwise add 0s as required by GMT
+ for arg in plot_lon, plot_lat, text:
+ if arg is None:
+ spec.append(0)
+ else:
+ spec.append(arg)
+
+ elif convention is None:
+ raise GMTError("We need a convention to know how to interpret the input!")
+
+ # if spec is not a dict it is handled here
+ kind = data_kind(spec)
+ with Session() as lib:
+ if kind == "matrix":
+ file_context = lib.virtualfile_from_matrix(
+ np.atleast_2d(spec)
+ ) # np.atleast_2d allows 1D and 2D arrays
+ elif kind == "file":
+ file_context = dummy_context(spec)
+ else:
+ raise GMTInvalidInput("Unrecognized data type: {}".format(type(spec)))
+ with file_context as fname:
+ arg_str = " ".join([fname, build_arg_string(kwargs)])
+ lib.call_module("meca", arg_str)