Source code for pygmt.src.surface

"""
surface - Grids table data using adjustable tension continuous curvature
splines.
"""
import xarray as xr
from pygmt.clib import Session
from pygmt.exceptions import GMTInvalidInput
from pygmt.helpers import (
    GMTTempFile,
    build_arg_string,
    data_kind,
    dummy_context,
    fmt_docstring,
    kwargs_to_strings,
    use_alias,
)


[docs]@fmt_docstring @use_alias( I="spacing", R="region", G="outfile", V="verbose", a="aspatial", f="coltypes", r="registration", ) @kwargs_to_strings(R="sequence") def surface(x=None, y=None, z=None, data=None, **kwargs): r""" Grids table data using adjustable tension continuous curvature splines. Surface reads randomly-spaced (x,y,z) triples and produces gridded values z(x,y) by solving: .. math:: (1 - t)\nabla^2(z)+t\nabla(z) = 0 where :math:`t` is a tension factor between 0 and 1, and :math:`\nabla` indicates the Laplacian operator. Takes a matrix, xyz triples, or a file name as input. Must provide either ``data`` or ``x``, ``y``, and ``z``. Full option list at :gmt-docs:`surface.html` {aliases} Parameters ---------- x/y/z : 1d arrays Arrays of x and y coordinates and values z of the data points. data : str or 2d array Either a data file name or a 2d numpy array with the tabular data. {I} region : str or list *xmin/xmax/ymin/ymax*\[**+r**][**+u**\ *unit*]. Specify the region of interest. outfile : str Optional. The file name for the output netcdf file with extension .nc to store the grid in. {V} {a} {f} {r} Returns ------- ret: xarray.DataArray or None Return type depends on whether the ``outfile`` parameter is set: - :class:`xarray.DataArray`: if ``outfile`` is not set - None if ``outfile`` is set (grid output will be stored in file set by ``outfile``) """ kind = data_kind(data, x, y, z) if kind == "vectors" and z is None: raise GMTInvalidInput("Must provide z with x and y.") with GMTTempFile(suffix=".nc") as tmpfile: with Session() as lib: if kind == "file": file_context = dummy_context(data) elif kind == "matrix": file_context = lib.virtualfile_from_matrix(data) elif kind == "vectors": file_context = lib.virtualfile_from_vectors(x, y, z) else: raise GMTInvalidInput("Unrecognized data type: {}".format(type(data))) with file_context as infile: if "G" not in kwargs.keys(): # if outfile is unset, output to tmpfile kwargs.update({"G": tmpfile.name}) outfile = kwargs["G"] arg_str = " ".join([infile, build_arg_string(kwargs)]) lib.call_module(module="surface", args=arg_str) if outfile == tmpfile.name: # if user did not set outfile, return DataArray with xr.open_dataarray(outfile) as dataarray: result = dataarray.load() _ = result.gmt # load GMTDataArray accessor information elif outfile != tmpfile.name: # if user sets an outfile, return None result = None return result