NCFTOOLS

A collection of Python tools for working with NetCDF files.

Installation

pip install -e .

Features

• meshinfo: Display mesh information from FlowFM NetCDF files (node/face/edge counts, element types, spatial extent)
• nc2shp: Convert a UGRID-compliant NetCDF mesh file to ESRI Shapefiles
• transzone1: Build a transition zone from triangle mesh faces and select all intersecting faces
• transzone2: Extract the core transition zone — faces fully within the shrunk zone

Usage

Check version

ncftools --version

List all available commands

ncftools-info

meshinfo

Display mesh information from a FlowFM NetCDF file.

meshinfo -i FlowFM_net.nc
meshinfo -h

nc2shp

Convert a NetCDF mesh file to ESRI Shapefiles. Outputs {stem}_faces.shp and {stem}_dissolved.shp in the output directory.

nc2shp -i FlowFM_net.nc
nc2shp -i mesh.nc -o output --crs EPSG:4326
nc2shp -i mesh.nc -q

transzone1

Buffer triangle mesh faces by +1 m to form a transition zone, then select all faces that intersect it. Outputs trans_zone.shp and trans_zone_extend.shp.

Triangles are identified from the type attribute column when present; otherwise they are detected automatically by vertex count (closed rings with 3 unique vertices).

transzone1 -i SHP_NC/FlowFM_net_faces.shp
transzone1 -i SHP_NC/FlowFM_net_faces.shp -o SHP_TRANS
transzone1 -i SHP_NC/FlowFM_net_faces.shp -q

transzone2

Shrink trans_zone_extend.shp (output of transzone1) by −1 m and select faces fully within the core zone. Outputs trans_zone_core.shp.

transzone2 -i SHP_NC/FlowFM_net_faces.shp -z SHP_TRANS/trans_zone_extend.shp
transzone2 -i SHP_NC/FlowFM_net_faces.shp -z SHP_TRANS/trans_zone_extend.shp -o SHP_TRANS
transzone2 -i SHP_NC/FlowFM_net_faces.shp -z SHP_TRANS/trans_zone_extend.shp -q

Python API

from ncftools import meshinfo

meshinfo.show_mesh_info("FlowFM_net.nc")