Name
oco — Orthogonal contours
Syntax
oco [frq frequency] [col color] [liw linewidth] [bsp] [nos] [noadj] [cur] [nrg] [dar] [trm] [ang] [cod] [cdc] [cdr] [chd] [split] [src]
Description
Display orthogonal contours from grids and generate drainage areas.
Arguments
frq frequency
Indicates density of orthogonal contour lines. Default is 7. Lower number gives higher density.
col color
Will be displayed in color color.
liw linewidth
Will be displayed with linewidth linewidth.
bsp
Will smooth the lines with b-splines.
nos
Will not seek for the deepest region (which is default).
noadj
Will not adjust the lines to lay slightly above the grid.
cur
Will produce one ortho contour from the cursor position.
nrg
No regridding or decimation for large grids.
Drainage area calculation
dar
Will produce drainage areas (which is closely related to orthogonal contours).
trm number_of_nodes
Remove drainage areas by minimum _number_of_nodes in areas.
ang angle
Remove drainage areas lower than a certain angle between areas.
cod
Combine two drainage areas defined by the two latest cursor positions.
cdc [lin] [col color]
Calculate a closed drainage curve for an area defined by the latest cursor position. The result curve is saved in workspace draincurve. The curve is smoothed by a spline unless the lin argument is used. Color of the curve can be set by col and color selection.
cdr [smo] [col color]
Calculate closed drainage curves for all drainage areas. The result curves are saved in workspace allcurves. The curve is linear unless the smo is used. Color of the curves can be set by col and color selection.
chd
Change a drainage area defined by the cursor position. This has an expanding effect of the drainge area.
split
Split a drainage area along a line defined by the two last cursor positions just outside the drainage area at opposite positions.
src
The dataset in active is set as the source grid in drainage calculation.
Examples
Ex.1: Orthogonal contours and drainage areas
z ;# Erase screen win demo ;# Get demo window (450000 460000 6450000 6460000 1000 4000) spe bgc whi ;# Specify background color to white mak ran 11 ;# Make 11 random points grp 222 222 ;# Make grid oco frq 14 col bla liw 2 ;# Draw orthogonal contours oco dar ;# Calculate drainage areas map drain ;# Map the drainage areas
The above example produces this image.
Orthogonal contours and drainage areas
See also
cal - Calculation algorithms, mak tan