I too have a csv file that has 4 fields of lat/lon. I can add x, y to 2 of the fields (Dlon/Dlat) but not too Plon/Plat. my dataframe is in NAD_1983_UTM_Zone_16N and when i add x,y i use wgs 84 . All my fields are numeric.
George, can you say what is your workflow and what product you are using? ArcMap 10.? or ArcGIS Pro 2.??
I added .csv file in Table of Contents using Pro 2.3 and I was able to select all four fields.
ArcMap 10.5.1
I cannot get PLon/Plat to plot out only Dlon/Dlat
open the table
sort descending
you have one crappy point
delete it from the csv file and re-add as an event layer
I cannot see that record when I sort descending, is my table limit reached in Arcmap concerning number of records?
Well it seems that when I work with a csv file I am only seeing 2000 records, cannot change that, if I export the csv to a file geodatabase then i see all records and the null value which we had missed in the original excel file.
You could even remove it in excel or fix it there, before bringing it into Arc*
That explains why you couldn't see it because the extent was totally off, so even 'zoom to layer' wouldn't work