topic ArcPy - retrieve scale-based symbol class min/max scales in ArcGIS Pro Questions

ArcPy - retrieve scale-based symbol class min/max scales

DavidPike — Fri, 28 Apr 2023 15:03:04 GMT

Hi,

ArcGIS Pro 2.8.1, Python either in notebook or IDLE.

I'm trying to create simple tool to list layer properties of any given aprx/mapx. I'm happy enough with retrieving the basic layer properties needed, however I can't seem to find a way of accessing unique symbol scale settings. https://pro.arcgis.com/en/pro-app/latest/help/mapping/layer-properties/scale-based-symbol-classes.htm

I've had a look at the unique value renderer Class but can't see anything jumping out at me. Also thinking of complications where scale-based symbology is set up..

Any ideas much appreciated.

#simple script to get layer scale import arcpy aprx = arcpy.mp.ArcGISProject("CURRENT") m = aprx.listMaps()[0] for lyr in m.listLayers(): if lyr.supports("dataSource"): print(lyr.name, lyr.minThreshold, lyr.maxThreshold)

Re: ArcPy - retrieve scale-based symbol class min/max scales

JohannesLindner — Fri, 28 Apr 2023 21:29:38 GMT

You have to dive into the CIM for that.

def get_min_max_scale(layer): result = dict() cim = layer.getDefinition('V3') renderer = cim.renderer try: symbol_classes = renderer.groups[0].classes except (AttributeError, IndexError): print("Symbology not applicable!") symbol_classes = [] for sc in symbol_classes: result[sc.label] = [sc.symbol.minScale, sc.symbol.maxScale] return result lyr_with_unique_symbols = arcpy.mp.ArcGISProject("current").activeMap.listLayers("TestPoints")[0] get_min_max_scale(lyr_with_unique_symbols) #{'capital': [0.0, 0.0], 'city': [500000, 0.0], 'town': [100000, 0.0], 'village': [50000, 0.0]} lyr_with_single_symbol = arcpy.mp.ArcGISProject("current").activeMap.listLayers("TestLines")[0] get_min_max_scale(lyr_with_single_symbol) #Symbology not applicable! #{}

Re: ArcPy - retrieve scale-based symbol class min/max scales

DavidPike — Fri, 28 Apr 2023 21:49:22 GMT

Absolute genius, thanks Johannes!