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joebocop
487 post(s)
#09-Jan-22 22:30

It's Sunday, and I might be missing something.

Is there already a function that takes a point geom source, a distance, and and azimuth, and returns the geom of a new point (or line segment ending) at the new location?

Thank you.

jsperr120 post(s)
#09-Jan-22 22:45

Try this topic in help.

https://manifold.net/doc/mfd9/traverses.htm

joebocop
487 post(s)
#10-Jan-22 01:56

We need a "like" button.

Thank you, the docs explain what I need to do; create the table using SQL, export as CSV, then import into the traverse dialog.

Cheers,

joe

dchall8
916 post(s)
#10-Jan-22 03:46

Like the idea of a like button.

Dimitri


6,899 post(s)
online
#10-Jan-22 06:36

create the table using SQL, export as CSV, then import into the traverse dialog.

? "Export a CSV"? No need for all those extra steps. Just create a new drawing, and create a line, interactively editing the traverse coordinates on the fly.

joebocop
487 post(s)
#10-Jan-22 21:21

Yeah, I think I have some work to do here, I don't *really* know the 2-d distances, only 3-d; I'm trying to create and visualize the lines in 2-d.

What I've got is two tables. One contains a few thousand "start" points having line_id, X,Y, and Z values.

I also have a table of survey points having line_id, "distance" (as measured from the start point on the ground with a hip-chain), azimuth (from the last survey point), and "dip" (being degrees above or below flat "0" from the previous survey point on that line).

If the "distance" is 20, but the dip is non-zero, then I need to first compute the 2-d distance the line should cover. Those facilities don't already exist in 9, do they? Where I would import a traverse file describing degree-changes in elevation over a distance, and the resulting 2-d line segment would measure the correct length in 2-d space?

Dimitri


6,899 post(s)
online
#11-Jan-22 07:00

Those facilities don't already exist in 9, do they?

Sure they do: use a computed field to get the 2-D length of the line from the angle ("dip") between that line and the length of the 3-D hypotenuse. But if you have an Esri-style traverse file, you already have those 2-D line lengths, right?

Mike Pelletier


1,966 post(s)
#11-Jan-22 14:34

Sounds like the pythagorean theorem formula in a calculated field is what you need. However, you also may need to deal with ground to grid conversion if your distances are large enough and your showing this on a map with other info.

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