pygmt.grdcut¶

pygmt.
grdcut
(grid, **kwargs)[source]¶ Extract subregion from a grid.
Produce a new outgrid file which is a subregion of grid. The subregion is specified with region; the specified range must not exceed the range of grid (but see extend). If in doubt, run
pygmt.grdinfo
to check range. Alternatively, define the subregion indirectly via a range check on the node values or via distances from a given point. Finally, you can give projection for oblique projections to determine the corresponding rectangular region setting that will give a grid that fully covers the oblique domain.Full option list at https://docs.genericmappingtools.org/latest/grdcut.html
Aliases:
G = outgrid
J = projection
N = extend
R = region
S = circ_subregion
Z = z_subregion
 Parameters
grid (str) – The name of the input grid file.
outgrid (str or None) – The name of the output netCDF file with extension .nc to store the grid in.
projection (str) – Required if this is the first plot command. Select map projection.
region (str or list) – Required if this is the first plot command.
'xmin/xmax/ymin/ymax[+r][+uunit]'
. Specify the region of interest.extend (bool or int or float) – Allow grid to be extended if new region exceeds existing boundaries. Give a value to initialize nodes outside current region.
circ_subregion (str) –
'lon/lat/radius[unit][+n]'
. Specify an origin (lon and lat) and radius; append a distance unit and we determine the corresponding rectangular region so that all grid nodes on or inside the circle are contained in the subset. If +n is appended we set all nodes outside the circle to NaN.z_subregion (str) –
'[min/max][+nNr]'
. Determine a new rectangular region so that all nodes outside this region are also outside the given zrange [inf/+inf]. To indicate no limit on min or max only, specify a hyphen (). Normally, any NaNs encountered are simply skipped and not considered in the rangedecision. Append +n to consider a NaN to be outside the given zrange. This means the new subset will be NaNfree. Alternatively, append +r to consider NaNs to be within the data range. In this case we stop shrinking the boundaries once a NaN is found [Default simply skips NaNs when making the range decision]. Finally, if your core subset grid is surrounded by rows and/or columns that are all NaNs, append +N to strip off such columns before (optionally) considering the range of the core subset for further reduction of the area.
 Returns
ret (xarray.DataArray or None) – Return type depends on whether the outgrid parameter is set:
xarray.DataArray if outgrid is not set
None if outgrid is set (grid output will be stored in outgrid)