Having trouble mapping XY data in ArcMap

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New Contributor II

Hi everyone,

This is my first ever post. I am having trouble mapping latitude and longitude coordinates in ArcMap. I am having trouble plotting XY coordinates in ArcMap 10.7. I imported points from a device called PocketLab. These are normal XY coordinates, but when I turned them into a feature class and tried to overlay them on the Oregon counties, they don't show up. I can confirm that the coordinate system and dataframe match for all my items.

 

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MVP Esteemed Contributor

Things should work fine from Excel. Just follow the step by step in the KB article and you should be fine.

You do not need a shapefile to plot points, they are "events" dynamically drawn from the table. You can then right click the event layer, save as shapefile or feature class once you have the points plotting on the map.

This is all detailed in the KB article.

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New Contributor II

I can't view the photos for some reason, so here they are again.

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MVP Regular Contributor

I suspect that your long-lat points don't have a defined Geographic Coordinate System (perhaps GCS WGS84)

and your map of Oregon seems to be in a web mercator projected coordinate system.  If your points don't have a defined coordinate system then they won't project-on-the-fly to that of the map.

 

data-management/define-projection 


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New Contributor II

Thanks for the quick reply. I tried using the Project (data management) tool to reproject all of my items to WGS 1984 Geographic Coordinate System. This didn't end up changing anything. I also tried setting my data frame to the same coordinate system as my items.

Since I can only seem to change the coordinate system of the data frame itself through the properties menu, I ended up using ArcToolbox to fix the problem. Points are still not showing up over the oregon shapefile even though I can confirm they are all in the same coordinate system.

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MVP Regular Contributor

Have you tried to add the coordinates to the table to confirm them.

Add XY Coordinates (Data Management)—ArcMap | Documentation (arcgis.com)


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MVP Esteemed Contributor

Nicholas,

Project will not solve your problem because the coordinate system was set wrong when you read in the points. You need to delete your points and start again. If you set the coordinate system in the Add XY dialog to match your XY coords in the table on the initial add xy to map , the points will plot on your map in the right place no matter what the data frame coordinate system is set to.

Please read the KB article I linked, it walks you through the process, step by step.

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MVP Regular Contributor

I should have added, when you calculate the coordinate system, don't specify an output coordinate system.  You want them to be in the shape's coordinate geometry as noted in the link

The output POINT_X and POINT_Y field values are based on the coordinate system of the dataset, not the coordinate system of the map display.

You don't want to do this part

To force the POINT_X and POINT_Y values to be in a coordinate system different than the input dataset, set the Output Coordinate System  environment.


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MVP Esteemed Contributor

This is not Nicholas's problem, he has go back and do it again, and this time set the coord system to match the xy coordinate his table from the get go, as he creates point events (per KB I linked).  (ArcGIS Pro is better at this, it looks at the table values and if it looks like geographic in the table, it auto-sets to GCS WGS84, not the map's CS.)

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MVP Regular Contributor

Based on what he said, I assumed he could tell whether the coordinates were in decimal degrees or in a projected coordinate system and defining them wrong wouldn't be an issue.

Perhaps doing it in ArcGIS Pro would be a better solution if ArcMap is still procedurally buggy


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New Contributor II

I appreciate the help. I'll give this all a try. Might I add that my ArcMap has given me a ton of problems, both inside and outside of my Coursera GIS class. Bugs, bugs everywhere. This program is a giant industry standard headache sometimes, but very rewarding once it does what I want it to.

Sounds to me that I need to reconvert the excel files into .csv and then make sure that the shapefile I have is already in ArcMap beforehand, then turn the coordinates into XY data. Since I had originally plotted the XY data before adding anything else, they were given their own coordinate system (which can't be altered). 

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