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I have a polyline shapefile with the attributes seen above.

startx and starty represent the coordinates of the beginning of each segment of a polyline. endx and endy represent the coordinates of the end of each segment of a polyline.

I have a raster with values of Flow Accumulation, known as FA.

I would like to extract the values on the raster at the coordinates of the start points and place them in this attribute table at "StartFA" and at the end points and place them in this attribute table at "EndFA".

I have so far performed "Feature Vertices to Points" using point types "START" and "END". I then performed "Extract Values to Points".

How do I put the values I am looking for into my polyline shapefile attribute table?

I am using ArcGIS 10.1 with an ArcInfo license.

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If I understand your question correctly, I run something similar on occasion for stormwater lines. It involves extracting depths at each endpoint and adding them to the table of the lines.

What you can do is create your own Unique ID's based off of the XY coordinates of both sources and then use those to join the tables together. You would end up doing two joins, one for the startFA and one for the endFA.

Add new fields called startFAXY and endFAXY in your lines table. Populate those by concatenating your coordinates of start and end. The startFAXY of FID0 would be "-76.350441, 45.434355". Run this same procedure on endFAXY. Then, continue this same process on your extracted values FA table so that you have a column that concatenates your FA table coords. Use these concatenated XY values as a unique ID to join the two sources together (lines table + FA table) and populate the field. The first join (startFAXY + FA table) would populate the startFA field. The second join (endFAXY + FA table) would populate the endFA field.

Using the example from above, FID0 startFAXY -76.350441, 45.434355 would join to a record in the FA table with a concatenated "ID" of -76.350441, 45.434355.

It is generally not perfect since it deals with coordinates, but I find I am able to capture >98% so any manual matching is not too bad. Add in the use of the Attribute Transfer Tool during cleanup/QA and it really reduces the headache.

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  • The extract values to points tool has populated my point files with the values I want. How can I put those values into my polyline attribute table? So many fields in both the point tables and the polyline table match.
    – JC11
    Commented Feb 27, 2014 at 16:29
  • I apologize if I explained that poorly. If you concatenate the X and Y into one field (in points and lines), you should end up with a unique, joinable field. Your concatenated start coords for lines would join to the concatenated startFA coords (same for endFA). Otherwise, yes, there will be a one-to-many issue if only the X or Y is used.
    – MapHound
    Commented Feb 27, 2014 at 16:43
  • I have performed the task and joined the point tables with the polyline table. This now leaves me with a lot of duplicate attributes, but includes 2 attributes representing the FA that I want to keep. Does the attribute transfer tool avoid this?
    – JC11
    Commented Feb 27, 2014 at 18:26
  • Is it possible the endpoints are duplicated, such as an endpoint for one line is the startpoint of another? The attribute transfer tool is more of a manual process requiring to click the source point then clicking the input point. If there are duplicate points, that may be a problem though.
    – MapHound
    Commented Feb 27, 2014 at 20:47
  • I used joinfield_management and that solved the issue.
    – JC11
    Commented Mar 3, 2014 at 17:04

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