shore.io.grd

Pack and merge Xall binary .grd mesh files. SHORE produces one .geo per block; write_grd concatenates them into the single Fortran-unformatted binary that the Xall solver consumes, and merge_grd concatenates multiple .grd files for multi-component Xall runs.

For the binary format and CLI, see shore grd and shore grd-merge.

write_grd

def write_grd(
    path: str | Path,
    geo_paths: list[str | Path],
) -> Path

Pack one or more .geo files into a single Xall .grd. The input list determines both the block count and the block ordering — which must match the ordering used to generate the companion cc.par.

Parameter	Description
path	Output file path. .grd extension appended if absent.
geo_paths	Ordered list of .geo paths, one per block. Must not be empty.

Returns the actual Path written.

The dimension records store cell counts (ni-1, nj-1, nk-1), not node counts. Coordinates are written as flat float64 arrays in Fortran column-major order (i-fastest), matching the format the Xall reader expects. Records use Fortran unformatted sequential binary format (4-byte length markers, native endianness).

merge_grd

def merge_grd(inputs: list[str | Path], out: str | Path) -> Path

Concatenate two-or-more .grd files into one. The merged file lists every block from inputs[0] first, then inputs[1], etc.; the header block count is rewritten to the sum. Shape and coordinate records are passed through byte-for-byte — no node values are touched.

Parameter	Description
inputs	Two-or-more input .grd paths, in the desired output order.
out	Output path. .grd extension appended if absent.

Returns the actual Path written.

Raises ValueError for fewer than 2 inputs or a malformed input file.

Coordinated invocation

Invoke merge_grd and shore.io.cc_par.merge_cc_paras a pair, with the same input ordering. The companion merge_cc_par shifts patch block-indices and family pointers (and box associated_block indices) to match the merged block list; without the matching cc.par the merged .grd is unusable.

from shore.io.grd import merge_grd
from shore.io.cc_par import merge_cc_par

merge_grd(
    ["background.grd", "wall.grd"],
    "assembly.grd",
)
merge_cc_par(
    ["background.cc.par", "wall.cc.par"],
    "assembly.cc.par",
    grd_filename="assembly.grd",
)

Example

from shore.io.grd import write_grd

write_grd(
    "wall.grd",
    [
        "wall_sub0.geo", "wall_sub1.geo",
        "wall_sub2.geo", "wall_sub3.geo",
        "wall_cap_north.geo", "wall_cap_south.geo",
    ],
)

See also

• shore grd CLI — the command-line wrapper for write_grd.
• shore grd-merge CLI — wrapper for merge_grd.
• shore.io.cc_par — the companion ASCII chimera descriptor.
• shore.io.geo — .geo reader / writer.