ch_checkchannels: Check Channels

In CSHS-hydRology/CSHShydRology: Canadian Hydrological Analyses

Check Channels

Description

Generates a map of the generated channel network layer.

Usage

ch_checkchannels(
  dem,
  channels,
  outlet = NULL,
  main_label = "",
  channel_colour = "blue",
  pp_colour = "red",
  contour_colour = "grey"
)

Arguments

dem	raster DEM that catchments were generated from
channels	channel polyline (or channels list from ch_wbt_channels) (sf object)
outlet	location of catchment outlet (sf object)
main_label	Main label for channel plot.
channel_colour	Colour for channel. Default is "blue".
pp_colour	Colour for catchment pour points. Default is "red".
contour_colour	Colour for contours Default is "grey".

Details

Generates a simple map of the drainage network plotted over the contours to allow a visual assessment.

Value

check_map

a ggplot object of a map with channel layer

Author(s)

Dan Moore

See Also

ch_checkcatchment

Examples

# Not tested automatically as requires installation of Whitebox
library(raster)
test_raster <- ch_volcano_raster()
dem_raster_file <- tempfile(fileext = c(".tif"))
no_sink_raster_file <- tempfile("no_sinks", fileext = c(".tif"))

# write test raster to file
writeRaster(test_raster, dem_raster_file, format = "GTiff")

# remove sinks
removed_sinks <- ch_wbt_removesinks(dem_raster_file, no_sink_raster_file, method = "fill")

# get flow accumulations
flow_acc_file <- tempfile("flow_acc", fileext = c(".tif"))
flow_acc <- ch_wbt_flow_accumulation(no_sink_raster_file, flow_acc_file)

# get flow directions
flow_dir_file <- tempfile("flow_dir", fileext = c(".tif"))
flow_dir <- ch_wbt_flow_direction(no_sink_raster_file, flow_dir_file)
channel_raster_file <- tempfile("channels", fileext = c(".tif"))
channel_vector_file <- tempfile("channels", fileext = c(".shp"))
channels <- ch_wbt_channels(flow_acc_file, flow_dir_file, channel_raster_file,
channel_vector_file, 1)

# get pour points
pourpoint_file <- tempfile("volcano_pourpoints", fileext = ".shp")
pourpoints <- ch_volcano_pourpoints(pourpoint_file)
snapped_pourpoint_file <- tempfile("snapped_pourpoints", fileext = ".shp")
snapped_pourpoints <- ch_wbt_pourpoints(pourpoints, flow_acc_file, pourpoint_file,
snapped_pourpoint_file, snap_dist = 10)
ch_checkchannels(test_raster, channels, snapped_pourpoints)

CSHS-hydRology/CSHShydRology documentation built on Aug. 18, 2022, 4:44 p.m.