This command highlights depression contours by changing their layer, color, and adding tick marks. A depression contour is a closed contour line that leads to a local minimum such that there are no contour lines with a higher elevation within the contour. This routine finds the depression contours out of the selected polylines. The depression contours are highlighted, and the user selects which ones to label.
Layer name of existing contours <CTR>:
Enter
Layer name for depression contours <DCTR>:
Enter
Width for depression contours <1.0>: Enter
Tick Interval for depression contours <50.00>:
Enter
Tick Size for depression contours <6.0>:
Enter
Select the existing contours.
Select objects: Select all
the contour polylines, even the contours that aren't
depression contours.
Select objects: press Enter to conclude selection.
The program then sorts and displays the high and low elevations of
the selected contours.
Reading the selection set ...
Locating the depression contours ...
Highlight all or selected
depression contours [All/<Selected>]? A The "All" option changes all
contours identified as depression contours to the specified layer
and adds tick marks. The "Selected" option highlights
all contours identified as depression contours and then user
is prompted to select which ones to change to specified depression
contour layer and add tick marks to.
Drawing the depression contours ...
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Highlighted depression contours |
Pulldown Menu Location: Surface >> Modify Contours
Keyboard Command: depress
Prerequisite: Contours should be plotted and visible on the
screen.