topo-create v3.2.3¶

Mercurial revision 5786:5c8b45563631 | 2026-08-04

Description¶

topo-create is a tool designed to create a new Digital Terrain Model (MNT). It allows users to merge multiple input files, specify grid resolutions, and customize output formats.

Usage¶

topo-create -o output [OPTIONS]

Options¶

General Options¶

Option	Description
`--help`, `-h`	Display help and exit.
`--debug`	Enable debug verbose mode.

Grid Specification Options¶

Option	Description
`-z <name>`	Preset zone name for grid specification.
`-n <file>`	Notebook file for grid specification.
`-g <file>`	Path to the grid file.
`-m <file>`	Path to the mesh file.
`--mapping <frame_resolution>`	Frame and resolution for the grid. Template: `[lon_min:dlon:lon_max;lat_min:dlat:lat_max]`. `dlon` and `dlat` support degrees, minutes, and arcseconds.
`--spherical=true`	Use spherical coordinates (default: `true`).
`--spherical=false`	Disable spherical coordinates.

Input Options¶

Option	Description
`-b <file>`	Path to an MNT file to be merged. Multiple calls allowed.
`-q <file>`	Path to a quadtree MNT file to be merged. Multiple calls allowed.
`-l <file>`	Path to an ASCII file containing all the files to process. Use `-iP` to set the input path.
`-iF <format>`	Input format. Supported formats: `grd`, `grd-float`, `nectdf`, `xyz`.
`-iP <path>`	Input path to read multiple files (used with `-l`).
`-v <name>`	Variable name in input files (must be unique).
`-mask <value>`	Mask value to apply.

Depth/Altitude Options¶

Option	Description
`-inv`	Toggle depth/altitude (invert sign).
`-zmin <value>`	Minimum imported depth.
`-zmax <value>`	Maximum imported depth.

Output Options¶

Option	Description
`-o <output>`	Specify the output filename.
`-oF <format>`	Output format. Supported formats: `grd`, `grd-float`, `netcdf`, `xyz`. Default is `netcdf` if the output file ends with `.nc`, otherwise `grd`.
`-deflate <level>`	Compression level (0 to 9). Default is `0` (no compression).

Examples¶

Create a New MNT from a Grid File¶

topo-create -g grid_file.nc -o output.grd

Create a New MNT from a Mesh File¶

topo-create -m mesh_file.nc -o output.nc

Merge Multiple MNT Files¶

topo-create -b mnt1.grd -b mnt2.grd -o merged_output.grd

Merge Quadtree MNT Files¶

topo-create -q quadtree1.nc -q quadtree2.nc -o merged_quadtree.nc

Specify a Custom Grid Resolution¶

topo-create --mapping "[0:0.1:10;0:0.1:10]" -o custom_grid.nc

Use Spherical Coordinates¶

topo-create --spherical=true -g grid_file.nc -o spherical_output.nc

Disable Spherical Coordinates¶

topo-create --spherical=false -g grid_file.nc -o cartesian_output.nc

Process Files from a List¶

topo-create -l file_list.txt -iP /path/to/files/ -o merged_output.nc

Set Input and Output Formats¶

topo-create -iF xyz -oF netcdf -l file_list.txt -o output.nc

Invert Depth/Altitude¶

topo-create -inv -g grid_file.nc -o inverted_output.nc

Apply Depth Limits¶

topo-create -zmin -100 -zmax 100 -g grid_file.nc -o limited_depth.nc

Apply Mask Value¶

topo-create -mask 9999 -g grid_file.nc -o masked_output.nc

Enable Compression¶

topo-create -deflate 5 -g grid_file.nc -o compressed_output.nc

Environment Variables¶

topo-create does not explicitly rely on environment variables for its core functionality. However, it uses OpenMP for parallel processing. You can control the number of threads using:

Variable	Description
`OMP_NUM_THREADS`	Number of threads to use for parallel processing.

Example:

OMP_NUM_THREADS=4 topo-create -g grid_file.nc -o output.nc

Notes¶

Input Files:
- Supported input formats: grd, grd-float, netcdf, xyz.
- If no input format is specified, the tool attempts to infer it from the file extension.
Output Files:
- If no output format is specified, the default is grd unless the output filename ends with .nc (then netcdf is used).
- Compression (-deflate) is only applicable for netcdf and grd-float formats.
Grid and Mesh Files:
- Use -g for grid files and -m for mesh files.
- The --mapping option allows fine-grained control over grid resolution and extent.
Merging Files:
- Use -b for merging standard MNT files and -q for quadtree MNT files.
- Multiple files can be merged by specifying -b or -q multiple times.
Depth/Altitude:
- Use -inv to toggle between depth and altitude.
- Use -zmin and -zmax to filter depth values outside the specified range.
Masking:
- The -mask option allows you to specify a value to use as a mask for missing or invalid data.