Symbology with more than 200 unique values needed

[MaxRingler1]

Hello,

this is an ArcMap to ArcGIS Pro transitioning question:

I am studying animal movement and space use in populations of often more than 200 individuals (frogs, salamanders, geckos). In ArcMap there was no problem to symbolize these individuals with unique combinations of 15 symbols and with then randomly assigned background colours, based on their "Individual" field. I do not need to identify individuals from a legend, but I need to be able to distinguish between close individuals in an area. Labels don't do the job for me, as they do not provide immediate visual information which points belong together (to one individual).

I now came to realize that apparently, I cannot create a symbology with more than 200 unique values in ArcGIS Pro - although no error message is shown, additionally added unique values after the 200th are simply discarded when trying to add them or when I try to automatically classify layers with more than 200 unique values. Oddly, when I import my old ArcMap layers with their *.lyr files that contain their old symbology, I readily get more than 200 unique values this way. However, creating these large symbologies via ArcMap is not a sustainable strategy for the future.

How can I keep on symbolizing my layers the way I do since 20 years? Isn't new software supposed to provide improvements over older versions?

Max Ringler
University of Bern

P.S.: Also the process of pre-defining unique values (before points with that values have been created) is now much more cumbersome than in ArcMap. There one could populate a field with values which then were established in one go. Now this requires 3 additional mouse clicks *per value* (open hamburger, add value, select value field, type in /paste values). A workaround is to create dummy points, assing them values in the respective fields, and then automatically add all new values, and then delete these points again - but this is not how a straightforward creation of large symbologies should work. 

[ODWC_GIS]

Isn't new software supposed to provide improvements over older versions?

You've been using ArcGIS for 20 years, and can still type that with a straight face?  🤔

The "workarounds" we've come up with and utilized throughout the ArcMap days are alive and well in ArcGIS Pro. 

I don't have a solution for you, so much as a couple ponderous potentials:

• Have you considered breaking up your layers?  Not actually splitting them into different feature layers, of course, but making several copies of the layer within a single map.  Each copy uses a Definition Query to display only a portion of the available data; stagger your dataset across several 'copy' layers.  To anyone just looking at the resulting map, they wouldn't know about the fishy means of producing the expected result.
  • As for the symbols/colors themselves, you can symbolize features based on field values.  Maybe an equation to create RGB values, or a bit of a color-shift for each 'copy' layer?

• I know you said Labels were a non-solution, but it is possible to set the label text as "_" while setting the text color's transparency to 100%... then enabling Callouts and configuring it to be the point symbol you want.  It's a ham-fisted approach, but it's what I've been using to symbolize point locations when there are a lot of point features in a single area, and I'd like them to 'move around' to avoid overlapping one another.