Reclassify label display using ArcPy?

Question

I can't seem to figure out or find a work around for the symbology labels after a reclassify when trying to automate maps. I run the following code and it is almost doing exactly what i want it to do. After I change a data source path I run the following 2 lines of code. The layer is set to have the colors i want and the numbers match what should be there. The only issue is the display of the labels for the classification.

                arcpy.mapping.UpdateLayer(df, lyr, updateLayer, True) 
                lyr.symbology.reclassify() 

The map is set to have 1 decimal place as is the layer file but after the reclass it is set to 4 significant digits.

Does anyone have any thoughts?

This is the one thing i need to fully automate the maps i am working on. It seems crazy that after doing a change path and a reclass that i have to open the mxd reset the layer properties and then update notes that i have generated based on the new classes with the update ranges.

Answer 1

I think you're expecting too much from 'reclassify'; rather you should be doing a manual classification, or apply this sample code below (untested) to refresh based on specific 'breaks' which of course you define:

# from GraduatedColorsSymbology example 2 in web help    
import arcpy
mxd = arcpy.mapping.MapDocument(r"C:\Project\Project.mxd")
df = arcpy.mapping.ListDataFrames(mxd, "Census")[0]
lyr = arcpy.mapping.ListLayers(mxd, "StatePopulation", df)[0]
lyrFile = arcpy.mapping.Layer(r"C:\Project\LYRs\Population.lyr")
arcpy.mapping.UpdateLayer(df, lyr, lyrFile, True)
if lyr.symbologyType == "GRADUATED_COLORS":
  lyr.symbology.valueField = "POP2000"
  lyr.symbology.classBreakValues = [250000, 999999, 4999999, 9999999, 35000000]
  lyr.symbology.classBreakLabels = ["250,000 to 999,999", "1,000,000 to 4,999,999", 
                                        "5,000,000 to 9,999,999", "10,000,000 to 35,000,000"]
arcpy.mapping.ExportToPDF(mxd, r"C:\Project\Output\StatePopulation.pdf")
del mxd, lyrFile

Answer 2

I fixed the problem by building the range myself as suggested. It just came to me!

Here is the solution. you can add lower range to set the labels as suggested by T. Wayne or just use the range for a some notes i needed to create on the map.

lower_range1 =  "{:.1f}".format(lyr.symbology.classBreakValues[0]) + " - " + "{:.1f}".format(lyr.symbology.classBreakValues[1])

lower_range2 =   "{:.1f}".format(lyr.symbology.classBreakValues[1] + .1) + " - " + "{:.1f}".format(lyr.symbology.classBreakValues[2])

lower_range3 =   "{:.1f}".format(lyr.symbology.classBreakValues[2] + .1) + " - " + "{:.1f}".format(lyr.symbology.classBreakValues[3])

lower_range4 =   "{:.1f}".format(lyr.symbology.classBreakValues[3] + .1) + " - " + "{:.1f}".format(lyr.symbology.classBreakValues[4])