points to line

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05-08-2012 11:58 AM
KaileyAdams
New Contributor II
Okay, so I'm trying to use the points to line tool. I've used it before and it has worked fine. But for some reason now whenever I use the tool it will do its thing at the bottom of the screen and act like it's going to give me something. And it does, kind of. When the tool finishes running a new layer will pop up on the left side, i.e., January_1998_points_to_lines. And this is fine, and it will have whatever symbol it was randomly assigned under it. This is what happens when things go right, except for the fact that no lines pop up on the map when the layer does. It is just the layer, and after the layer pops up, if I try to click anything at all the program will not respond and I have to shut it down. This is really getting frustrating. I'm very new to this stuff so it could be a simple fix, but I have no idea. If anyone could help I would really appreciate it!
13 Replies
DanLee
by Esri Regular Contributor
Esri Regular Contributor
Kailey,

I understand your frustration, but I would like to take a few more steps to track the problem.

1. Continue from where you are - you have an output from Points To Line, but not shown in map:
       Open a new map, not an existing one, and add that output to the map. Do yo see any lines?
       If not, right-click the layer and open the attribute table. Are there any records?

       Add the point data to the map. Right-click the point layer, select "Properties ...".
       Under the "Source" tab, do you see the GCS_WGS_ 1984  information?

2. To verify whether the Points To Line tool works on your computer:
       Please get the attached zip file - it contains a shapefile with 5 points and a field, ORIG_FID. Unzip the file to a folder.
       Open a new map, not an existing .mxd. Add myPoints.shp to the map.
       Run Points To Line tool, specify the ORIG_FID as the Line Field, and give an output name.
       Does the tool run successfully? Do you get two lines in the output? Does ArcMap freeze?
       Can you repeat the process again with a different output name?
       If this works, the tool works.

I have stated that I am using ArcGIS 10.0 SP3. Do you have any ArcGIS 10.0 SP on your computer? To check in ArcMap:
       Click "Help" on top of the window and then select "About ArcMAp ...". Do you see any ArcGIS 10.0 Service Pack number?

Thanks for your patience.
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KaileyAdams
New Contributor II
I added the points to line layers, the ones that wouldn't show up before, to a new map. The lines showed up this time. There are records and the information under the source tab does specify GCS_WGS_1984. There is a problem with the lines though, it is described below.

I downloaded the zip file you included and tried everything you said, and it all worked. So the tool must be working.
When I look under the "Help" and "About ArcMap..." It says that it is ESRI ArcMap 10.0 and farther right in parentheses it has (Build 2414).

I tried adding data again, out of curiosity, to see what would happen. Surprisingly, I got a different result. Each time I add data and use the points to line tool (I have done this several times tonight, but only tonight) the tool runs and gives me an output that appears on the screen without the program shutting down. But this output is not what I expected, I'll attach a screen shot so you can see, but there are several horizontal lines running across the map, which I know should not be there. The number of lines, and the placement, differ with each month and year I work with, but the same types of lines always appear. I'm not sure what is causing this, because it has not happened before (except when I added the lines which didn't work before to a new map document).

I have attached a screen shot of the output of my data and the excel file that goes with it.
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DanLee
by Esri Regular Contributor
Esri Regular Contributor
Kailey,

Thank you for taking the steps I suggested and confirming that the Points To Line tool works fine on your machine. The problem you had with ArcMap might be just "hiccups", depending on what had been done prior to the process in that map or even what other software or extension(s) were running or had been used at the time.

It seems you don't have any SP on your ArcGIS 10. Thanks for checking that.

Using your 2000 data, I reproduced the display as shown in your image. The GCS used in the display covers from 0 degree (left edge of the map) to 360 degrees (right edge of the map). So, when a line segment goes from longitude 350 degrees to 2 degrees, it is that long. For example the line of Storm value 76 is made up with 7 vertices; the longitude of the 4th vertex is 357.5 degrees and longitude of the 5th vertex is 2.5 degrees, so it is a long line; and technically it is drawn correctly in this "cartesian" like display coordinates.

I understand that in reality those two vertice are only a few degrees apart in longitude. So, one would expect that the line is drawn from 357.5 longitude to 360 and then restart from 0 degree longitude and end at 2.5 degrees (I am omitting the latitudes here). However the current system doesn't know that the line should wrap around the 360 or 0 degree meridian, so it just follows the coordinate values as in a Cartesian system.

Technically the Points To Line produces the line correctly, following the order of the point coordinates. You didn't see this problem before probably because the lines you had in the past didn't cross the 360 or 0 longitude or you used a projection in which this issue wouldn't occur. Can you tell which reason it might be from your side?

I am not sure what workaround is the best; some colleagues suggest that you first decide what GCS you will use to display your data and then edit the point coordinates so that a line wrapping around 360 or 0 degree longitude should have a vertex at 360 and restart with a vertex at 0 longitude. That way the line will be drawn following the given coordinates.

I have brought up this subject to our team - whether it is possible for our system to support the drawing with an option of going the "shorter" side of the globe. There may not be an easy answer very soon.
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NaimeCelik
Occasional Contributor

Did anyone find solution to how to work this tool? No matter what I did, it just not working and giving error 9999999 or warning 001059.