C3d-Batch snap points to a line

[Ben_T181598]

I am trying to snap surveyed river single beam bathymetry points to a common line for input into a 1D hydrodyamic model. I know there is a way to do this in GIS but life would be a lot easier if i can do it in C3d. i can turn OSNAPZ to 1 and manually snap perpendicular to a best fit polyline but takes too long for the amount of points i need to process. I would like to able to batch select a bunch of points and snap them to a line. Or take a line and inherit the elevations of adjacent points given some tolerance. Something like that.

Thanks for any help.

-B

[Novarese]

Would you please elaborate it graphically, by means of a screenshot or a sketch..?

[Tom Beauford]

I doubt if many are going to know what "surveyed river single beam bathymetry points" are. If they are in C3d you can produce a surface with them, not sure how that relates to a "1D hydrodyamic model" whatever that is. A standard polyline has only one elevation, you would need a 3Dpolyline or better yet a feature line for it to have the elevations of those points.

You will have better luck getting C3d answers using C3d terms in your questions so C3d folk can read them.

[Richard McDonald]

Taking that the single line was the only survey done (for centre river for instance) and a surface cant be produced to suit your needs.

Get a .csv file from the sounder software. Then changing all the x or y co-ordinates to match the first in the file. Using civil or one of the many lisps on the net, input back into you drawing and you will end up with your "best fit line" this can then be rotated to suit the base mapping.

Regards

[Tom Beauford]

Taking that the single line was the only survey done (for centre river for instance) and a surface cant be produced to suit your needs.

Just recently produced a narrow surface from shots taken along the centerline of an easement with no angle breaks. All I needed was for the shots to not be in a perfect straight line to produce a narrow surface to label the contour elevations. I wouldn't expect those river points to be in a perfect straight line either. He might draw and extract a profile line from the surface,but I don't follow the terms he's using so your modification of the csv file may be the best solution.

[Ben_T181598]

Sorry if there was confusion. Attached is an example of a surveyed transect taken by boat (no need to worry abt how it was collected, Position RTK GPS - depth given by echosoundser) I cut a best fit line in xy to represent where i want the points to fall. I know we don't want to move surveyed data but this method is acceptable given the degree of accuracy associated with hydraulic modeling. The slow method would be to drag and snap perpendicular the COGO points to the polyline still keeping the Z value in place by setting OSNAPz to 1. This is not feasible for big surveys where we might collect 10's of thousands of points with 100's of transects. Ultimately what i export into the model will be a 2 column csv with just STA, and elevation. The snapping to a line step is important because if you just do a distance formula from NE values you are overestimating the overall width of the channel. I can also create 3d polylines or feature lines between the points very efficiently, if that helps, using polyline transparent commands. Also there are automatic ways to create best fit lines that can be weeded by leanear regression values that i then convert to 3d polys or feature lines. 9-16-2013 3-45-00 PM.png