vis_river: Visialize DEM river as lines (not raster)

In brry/mhmVis: Visualisation of 'mHM' Input and Output Files, Including 'netcdf' Files

Description

Convert flow accumulation raster to line segments and plot it. This enables much faster drawing, making it suitable e.g. for drawing small maps with the river added on top in the corner of plots, e.g. with berryFunctions::smallPlot as in the example.

Usage

vis_river(dem, proj = NA, prop = 0.98, col = rivPal(n = 150), lwd = 1:6,
  add = FALSE, legend = TRUE, title = "Catchment area  [1000 km^2]",
  legargs = NULL, quiet = FALSE, ...)

Arguments

dem	List returned by read_dem or character string giving a directory (passed to read_dem).
proj	Projection passed to read_asc. DEFAULT: NA
prop	Proportion of catchment areas (of each raster cell) beyond which a channel counts as river. Lower values mean longer stretches identified as rivers. DEFAULT: 0.98
col	Color scale. DEFAULT: rivPal(n=150)
lwd	Line width range. DEFAULT: 1:6
add	Logical: add to existing plot? DEFAULT: FALSE
legend	Logical: add colPointsLegend? DEFAULT: TRUE
title	Character: Legend title. DEFAULT: "Catchment area [1000 km^2]"
legargs	List of arguments passed to colPointsLegend.
quiet	Logical: should progress messages be suppressed? DEFAULT: FALSE
...	Further arguments passed to segments.

Value

data.frame with segment indices

Author(s)

Berry Boessenkool, [e-mail], Mar 2017

See Also

vis_dem, read_dem

Examples

# To be added

if(FALSE){
dem <- read_dem("U:/mHM_shared/basel_6935051/input/morph", proj=3035)
op <- par(no.readonly=TRUE)
vis_dem(dem, png=FALSE)
riv <- vis_river(dem)
par(op)
ca <- riverlines(dem, riv, col="orange")
# for large catchments, computing is time consuming, so plotting can be outsourced

library(berryFunctions)
logHist(dem$facc*(facc$cellsize/1000)^2, breaks=30) # km^2
}

# Add rivers as small plot
## Not run:  ## Not run in CRAN checks to avoid downloading background map
library(OSMscale)
map <- pointsMap(lat=riv$y, lon=riv$x, zoom=7, proj=pll(), plot=F)
par(mar=c(0,0,0,0))
plot(map, removeMargin=FALSE)
vis_river(facc, add=TRUE, lwd=1:3)

par(op)
plot(cumsum(rnorm(300)), type="l") # some gauge properties, e.g.
smallPlot({
        plot(map, removeMargin=FALSE)
        vis_river(facc, add=TRUE, lwd=1:3, legend=FALSE)
        points(8, 47.55, col="red", pch=3, lwd=3, cex=2)
        }, x1=0, x2=0.4, y1=0.77, y2=1, mar=0, border=NA, bg=NA)


## End(Not run) # end dontrun

brry/mhmVis documentation built on May 13, 2019, 7:53 a.m.