Hi,
There are lots of ways of doing it.
If you wish to stay in a spreadsheet do this:
Isolate one of the layers containing Points
Make a Point Group of the points on that layer
Repeat for the other layer
Export each to the point groups to CSV files containing Point number,
easting, northing and elevation
Insert each file into separate worksheets in Excel
Sort each worksheet by Northing, then Easting
Copy the A,B,C and D columns from one worksheet to columns H,I,J and K in
the other worksheet
In column E create a difference value between the Eastings in columns B and
I
In column F create a difference value between the Eastings in columns C and
J
Use an If value in the formula so that the value only displays if the
difference exceeds 0.1 or some other sutiable value
Check the results to see if all the differences are OK - such that all point
rows contain matching points
If not move the data till you are satisified you have matching locations
Create the elevation difference in column G between columns D and K
However, Joe's advice to use the LDT tools and create a differential
surface is a far far better solution.
Not only does it entail less work and not require Excel, but you can plot
contours of the surface on different layers to get different colours for cut
and fill, and plot the zero contour to get the boundary of cut and fill etc.
--
Laurie Comerford
CADApps
www.cadapps.com.au
www.civil3Dtools.com
wrote in message news:5666075@discussion.autodesk.com...
I have two sets of points that fall in a 25' grid. The first set has
elevations established conventionally. The second set has elevations
established by another high-tech method. It is easy to compare their
elevations visually in the drawing, since their positional horizontal
accuracy is less than 5 hundreds of a foot.
Now I'm being ask to select these points and create a Comma Delimited File
(CSV) in Excel to create a spreadsheet to show their differences. Point
numbers are not consecutive on these two sets. How can I do that easily? Is
there any way to perform this task? We have thousands of points and doing
this manually would take forever. Is there a special function I need to know
about?