Source code for pygmt.gridding

GMT modules for Gridding of Data Tables
import xarray as xr

from .clib import Session
from .helpers import (
from .exceptions import GMTInvalidInput

[docs]@fmt_docstring @use_alias(I="spacing", R="region", G="outfile") @kwargs_to_strings(R="sequence") def surface(x=None, y=None, z=None, data=None, **kwargs): """ 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: (1 - T) * L (L (z)) + T * L (z) = 0 where T is a tension factor between 0 and 1, and L 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. spacing : str ``'xinc[unit][+e|n][/yinc[unit][+e|n]]'``. x_inc [and optionally y_inc] is the grid spacing. region : str or list ``'xmin/xmax/ymin/ymax[+r][+uunit]'``. Specify the region of interest. outfile : str Optional. The file name for the output netcdf file with extension .nc to store the grid in. Returns ------- ret: xarray.DataArray or None Return type depends on whether the outfile (G) parameter is set: - xarray.DataArray if outfile (G) is not set - None if outfile (G) is set (grid output will be stored in 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":}) outfile = kwargs["G"] arg_str = " ".join([infile, build_arg_string(kwargs)]) lib.call_module(module="surface", args=arg_str) if outfile == # if user did not set outfile, return DataArray with xr.open_dataarray(outfile) as dataarray: result = dataarray.load() elif outfile != # if user sets an outfile, return None result = None return result