GISGEARS

A collection of Python tools for GIS/hydrology raster and vector analysis.

WhiteboxTools: wsdgen depends on the WhiteboxTools executable, which the whitebox Python package downloads automatically the first time it runs.

Installation

pip install gisgears

Features

• wsdgen: Delineate a watershed from a DEM and an outlet layer (point or line)
• wsdpyshed: Delineate a watershed and stream network from a DEM and an outlet (point or line) using pysheds (no WhiteboxTools needed)
• showtif: Display a DEM GeoTIFF with an elevation colormap and hillshade
• showshp: Display one or more shapefiles overlaid on a single map
• showtable: Print the attribute table of a shapefile or GeoPackage layer

Usage

Command-line

# List all available commands
gisgears-info

# Delineate a watershed from a point outlet
wsdgen --dem dem.tif --outlet outlet.shp

# Delineate a watershed from a line outlet (e.g. a cross-section), keeping intermediates
wsdgen --dem dem.tif --outlet crosssection.shp --all-outputs

# Use a coarser/finer boundary-smoothing filter
wsdgen --dem dem.tif --outlet outlet.shp --smooth-filter 15

# Delineate with pysheds from a pour point shapefile or x/y coordinates
wsdpyshed --dem dem.tif --outlet pourpoint.shp
wsdpyshed --dem dem.tif --outlet crosssection.shp   # line outlet
wsdpyshed --dem dem.tif --xy 285612.0 2936416.7 --acc-threshold 500 --plot

# Inspect a DEM (prints CRS/size/stats, plots elevation + hillshade)
showtif dem.tif

# Overlay shapefiles on one map, labelling features by a column
showshp WSD/watershed.shp outlet.shp -l Station

# Print an attribute table (selected columns, with geometry as WKT)
showtable thiessen.shp -c Station -g
showtable data.gpkg -l roads -n 20
showtable data.gpkg --list-layers

Python API

from gisgears import wsdgen

# Delineate a watershed (written to WSD/watershed.tif, watershed.shp, watershed_smooth.shp)
wsdgen.delineate_watershed(dem="dem.tif", outlet="outlet.shp")

from gisgears import wsdpyshed

# Same idea with pysheds; also writes dem_clipped.tif and streams.gpkg/.geojson to WSD/
wsdpyshed.delineate_watershed(dem="dem.tif", outlet="pourpoint.shp", acc_threshold=200)

from gisgears import showtif, showshp, showtable

showtif.show_dem("dem.tif")
showshp.show_shapefiles(["WSD/watershed.shp", "outlet.shp"], label="Station")
table = showtable.show_table("thiessen.shp", columns=["Station"])  # returns a DataFrame
layers = showtable.list_layers("data.gpkg")  # [(name, geometry type), ...]

Notes

• The outlet layer may be a point shapefile (a single manually-marked outlet) or a line shapefile (e.g. a cross-section at the watershed outlet); wsdgen detects the geometry type automatically.
• By default only the final watershed.tif, watershed.shp and watershed_smooth.shp are written to the WSD/ output directory; pass --all-outputs to also keep intermediate files (breached DEM, D8 pointer, flow accumulation, snapped outlet, etc.) there instead of a temporary folder.
• wsdpyshed takes a point or line outlet (--outlet, reprojected to the DEM's CRS if needed; pick a feature with --outlet-index) or coordinates (--xy). The pour point is snapped to the nearest cell whose flow accumulation exceeds --acc-threshold (default 200, also used for the stream network) unless --no-snap is given. A line outlet (e.g. a cross-section) is rasterized and the watershed is everything draining to any cell it crosses; if it crosses no stream cell, its highest-accumulation cell is snapped like a point. Outputs go to WSD/ by default: watershed.tif, watershed.shp, dem_clipped.tif, streams.gpkg and streams.geojson; --all-outputs adds the conditioned DEM, flow direction and flow accumulation rasters, and --web-map writes streams_map.html (requires folium and mapclassify).