Importing terrain data csv

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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.

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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.

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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.

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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:

• 2
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Very nicely done.

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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:

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.

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21 minutes ago, KimHist said:

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.

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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.

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I found the outliers!