digger.make.breach

Module Contents

Functions

breach

Modify provided topography to add breaches, usually to crossing structures.

API

digger.make.breach.breach(topo_path: str, breach_path: list = [], b_prefix: str = 'b', all_touched: bool = False, west: float | None = None, south: float | None = None, east: float | None = None, north: float | None = None, write_tif: bool = True, write_tt3: bool = False, fig_path: str = 'breach.png') → None

Modify provided topography to add breaches, usually to crossing structures.

Digital elevation models reflect a two-dimensional surface and sometimes this results in three-dimensional structures (e.g., bridges and culverts) represented as dams. digger.make.breach provides an approximate method to modify a DEM to remove bridges or similar structures.

The user prepares a polyline-type file that contains information about the start and end points of each breach. This polyline is buffered based on a user- specified width. Within the raster grid cells covered by the buffered breach segment the topography is modifed to reflect a planar surface that slopes from the (x,y,z) location of the starting pont to the (x,y,z) location of the ending point.

from digger import make
topo = 'path/to/input/topography.tif'
breach = 'path/to/input/breaches.shp'
make.breach(topo_path=topo, breach_path=breach)

Inputs:

topo_pathstr

Path to rasterio-readable file containing the initial topography input file. Output is written at the resolution of this file. Expected in projected coordinates (e.g., meters or feet, not degrees).

breach_pathstr

Path to fiona-readable file containing polyline-type records indicating the extent of each breach. On row per breach, indicating the start and end of the area to be modified. Only two coordinates per row (that is, no multi-segment lines). The file should include an attribute width_m reflecting the full width of the breach.

b_prefixstr

Prefix of the path to write any output of b (eta-h).

all_touchedbool

Option passed to rasterio.features.rasterize that controls which raster grid cells are considered. See here for additional details.

westfloat

The extent within topo_path to consider for this analysis. Along with west, east, and north, this parameter may reduce the size of the terrain consider, speeding computation time and reducing file size.

southfloat

The extent within topo_path to consider for this analysis.

eastfloat

The extent within topo_path to consider for this analysis.

northfloat

The extent within topo_path to consider for this analysis.

write_tt3bool

Whether to write out topotype 3 files b. If written, the b_prefix has ‘.tt3’ added to the end.

write_tifbool

Whether to write out geotif files of b. If written, the b_prefix has ‘.tif’ added to the end.

fig_pathstr

The base filepath for figures generated. The file extension will be used by matplotlib to determine the type of file (png, pdf, etc).

Output:

None