Importing terrain data csv

[KimHist]

Good afternoon, folks. I need to import terrain data in the form of elevation points as a csv.  I have a file of 280 points in x,y,z format, covering 5 acres.  I am using X14.  I tried following the instructions in videos and in this thread: 

I just see a cross (not an x) when I import the data (shown here in a blank plan).  What unit should I be using "to define elevation points" for X & Y.  I know that Z is ft.

I appreciate any assistance.

blank plan terrain data.plan 53Cbulkel.csv

[Alaskan_Son]

I would start by figuring out what measurement is being used in the source file.  Its not that your points aren't being imported.  Its just that they're all essentially stacked right on top of each other since the X and Y values are almost all identical and only differ by a fraction of their respective units. 

[KimHist]

Thank you, Michael.  They are standard coordinates, so degrees.  After I posted I did try converting them to feet, but it didn't seem to help.

[Alaskan_Son]

You'll either need to convert them in Excel or do the conversion after the fact.  Per the USGS:

 

Quote

 

The distances vary. A degree, minute, or second of latitude remains fairly constant from the equator to the poles; however a degree, minute, or second of longitude can vary greatly as one approaches the poles and the meridians converge.

At 38 degrees North latitude (which passes through Stockton California and Charlottesville Virginia):

• One degree of latitude equals approximately 364,000 feet (69 miles), one minute equals 6,068 feet (1.15 miles), and one-second equals 101 feet. 
• One-degree of longitude equals 288,200 feet (54.6 miles), one minute equals 4,800 feet (0.91 mile), and one second equals 80 feet.

 

 

If you know how to do the math, you can do it yourself, otherwise you can use any number of online calculators like this one HERE to figure out more precisely how many feet per degree at any given latitude.  At your location in Arkansas (derived from the coordinates you posted) it looks like each degree of longitude(X) is approx. 299521.53 ft. and that each degree of latitude(Y) is approx. 363977.13 ft.  You would just want to enter those conversion factors during the Import process like so:

 

 

You could also optionally do the conversion in Excel prior to importing.  Either way, using the aforementioned conversion factors, your results should look something like this:

 

 

 

 

 

[para-CAD]

Damn helpful right there!

Very nicely done. 

[KimHist]

1 hour ago, Alaskan_Son said:

You'll either need to convert them in Excel or do the conversion after the fact.  Per the USGS:

 

 

If you know how to do the math, you can do it yourself, otherwise you can use any number of online calculators like this one HERE to figure out more precisely how many feet per degree at any given latitude.  At your location in Arkansas (derived from the coordinates you posted) it looks like each degree of longitude(X) is approx. 299521.53 ft. and that each degree of latitude(Y) is approx. 363977.13 ft.  You would just want to enter those conversion factors during the Import process like so:

 

 

You could also optionally do the conversion in Excel prior to importing.  Either way, using the aforementioned conversion factors, your results should look something like this:

 

 

Thanks, Alaskan Son.
I did use those USGS numbers to convert after I posted, and I still couldn't see anything--except that shape, no data points.  Did I not wait long enough for it to load?  Also the property shape should be 330x660.

Hmmmmmm.

 

 

 

[Alaskan_Son]

21 minutes ago, KimHist said:

Thanks, Alaskan Son.
I did use those USGS numbers to convert after I posted, and I still couldn't see anything--except that shape, no data points.  Did I not wait long enough for it to load?  Also the property shape should be 330x660.

Hmmmmmm.

 

Regarding the fact you didn't "see anything":  You need Build Terrain one way or another.  One quick way is to simply click Terrain>Build Terrain.  Open and closing the actual Terrain Perimeter would do it as well.

 

If you import the points per my instructions, you should see that there are only 2 outlying points.  The vast majority fit nicely into an area almost exactly 660x330.  If you want the whole thing rotated, then you can either rotate after the fact or you can even set that during the import process.

[KimHist]

I tried again before I got your reply, and poof!  The build button worked. It looks like the program completed the contours well outside the zone of the 660x330 perimeter, resulting in the elongated form.  (Either that or Chief hung on to the data from the file that included a 278-foot elevation outlier that snuck in, instead of replacing it with the new one.)  I overlaid the lidar-generated contours and sorted it out.  Thank you!  
Now I need to get this terrain onto my house plan.  You've been so helpful here, that I hope you've got advice for adding it there.  Is it possible to copy the data from here?
Thank you again for talking me off my little ledge of frustration.

[KimHist]

I found the outliers!

[wazzubrad]

Hey Kim, I was able to get the data imported, but I also have the elongated terrain perimeter. Do you remember how you fixed this?

[KimHist]

On 5/5/2023 at 12:12 PM, wazzubrad said:

Hey Kim, I was able to get the data imported, but I also have the elongated terrain perimeter. Do you remember how you fixed this?

Yes, Brad, I  took some notes to be sure I'd remember most of the steps.  I imported an image of my property lines with topo data into Chief from GIS parcel records. Next I adjusted the image using the Chief measure tool to make sure I'd sized it to fit our property correctly (660 feet on the X axis by 330 on the Y axis).  Then I measured the imported terrain to determine how much the X data appeared to be off.  I got .8196 as the multiplier for the X axis, but yours may be different, because of course lat. and long. aren't the same type of data as 2D X/Y data.  I used that multiplier (.8196) and adjusted my Xs in the X-Y-Z elevation spreadsheet.  I then moved my image of the topo to the terrain data. The image of the topo was obviously less detailed but lined up well.  I imported a sat image with the same property boundaries (from GIS)  after I deleted the topo image.  I did all of these adjustments in a new plan and then used Edit>Edit Area (All Floors) on my house plan to import the house plan and position it.  I'm not 100% satisfied with my results, but they are pretty darn good, with 1-foot contours. I'm going to tweak it more later this week.

Did you use the 3DEP USGS tool for your elevation points? What it generates appears to be much more reliable than Garmin, but the lidar topo image doesn't overlay accurately with previous USGS topos.  My husband brought me a few data points (e.g. existing well) that he gathered with the Garmin.  They were clearly off, so a few Saturdays ago we got an extra-long measuring tape, and he held it at various points while I used my phone to walk due east to the road.  Those points line up fairly well (considering my need to duck around a few trees and the 10-foot increase and then 10-foot decrease in elevation) with what we can see for sure in sat images.

I hope my explanation makes sense.  Please let me know if it works for you or if you need a different multiplier.  I'm still refining my own data, so if you don't get good results with my "fix," I'd really appreciate knowing.  I have been extremely busy with my day job for the past month, but I should be able to get back to this work by next weekend.  Then some time during the week of 15th, I may reach out to the state GIS folks about the lidar data. 

[KimHist]

On 5/5/2023 at 12:12 PM, wazzubrad said:

Hey Kim, I was able to get the data imported, but I also have the elongated terrain perimeter. Do you remember how you fixed this?

Brad, I updated to X15 too, if that matters.

[KimHist]

On 5/5/2023 at 12:12 PM, wazzubrad said:

Hey Kim, I was able to get the data imported, but I also have the elongated terrain perimeter. Do you remember how you fixed this?

I also did not use this tool http://www.csgnetwork.com/degreelenllavcalc.html that Alaskan_Son posted to calculate more precisely for the location.  Did you?  Maybe that will fix the elongation.  If it does, let me know!

[wazzubrad]

Thank you Kim! That’s a great breakdown. I’m trying a couple different software tools, CloudCompare and QGIS, along with your method and help from Alaskan_Son, to see if I can get the USGS data imported into CC or QGIS and then exported into the correct coordinate format for chief to import. I’ve got it imported into chief, but it’s many more steps than I think it could be, partially due to the coordinate formatting. I’ll keep trying time allows.

[KimHist]

19 hours ago, wazzubrad said:

Thank you Kim! That’s a great breakdown.  . . .. I’ve got it imported into chief, but it’s many more steps than I think it could be, partially due to the coordinate formatting. I’ll keep trying time allows.

You're welcome!
I used the 3DEP USGS tool to click all over the property, recording the lat/long points in a spreadsheet.  Then I used the USGS elevation generator to get elevation points. Formatting was easy, just CSV I think. 

[KimHist]

I wish we could get the detailed lidar elevation data by section, because right now it is such large sets (looks to be bigger than townships) that it is almost impossible to download and use.

 

[wazzubrad]

Kim, have you used the software QGIS? With QGIS, we can clip the unneeded liar data to only what’s needed. I’m still learning, but was able to use it to clip and then export CSV file that I then imported into Chief via the Terrain Import tool. YouTube has some videos which were helpful. If I can refine this process, I will post a tutorial on the method.

[KimHist]

On 5/10/2023 at 8:58 PM, wazzubrad said:

Kim, have you used the software QGIS? With QGIS, we can clip the unneeded liar data to only what’s needed. I’m still learning, but was able to use it to clip and then export CSV file that I then imported into Chief via the Terrain Import tool. YouTube has some videos which were helpful. If I can refine this process, I will post a tutorial on the method.

Ooooh! Did you get something better than 3-meter contours?  If so, I'm really interested.  I wanted 1-foot contours.