How Can I Find The Missing Sequence Number in a Field in ArcGIS

[MAMDOUHZALAKY]

How Can I Find The Missing Sequence Number in a Field in ArcGIS I have thousand numbers on that field ? I have ArcGIS 10.8

[JohannesLindner · Accepted solution]

You can do it with a little Python script:

fc = "TestPolygons"  # path the the feature class or name of the layer
field = "IntegerField1"

# get a set of values in the field
values = {row[0] for row in arcpy.da.SearchCursor(fc, [field])}
# get a set of the complete range
complete_values = set(range(min(values), max(values)))
# the difference between these sets are the missing numbers
missing_values = complete_values - values
print(sorted(missing_values))

[MAMDOUHZALAKY]

what should I change in your Python script to work , I create field test to run your Python script but it does not work ,  I want to know the missing number in field parcel ….I need more details!!!

[MAMDOUHZALAKY]

[JohannesLindner]

The script is meant to be run in the Python Window, not in the Fieled Calculator.

• Open the ArcMap Python Window
• Copy/Paste the script into the window
• Change the first two lines
• Execute by pressing Enter (may have to press it twice)

[MAMDOUHZALAKY]

Ok now its work …. but can we make another change in the python script to let him give us the missing number in group A and the missing number in group B , because the missing number in group A is different than the missing number in group B.

[JohannesLindner · Accepted solution]

fc = "TestPolygons"  # path the the feature class or name of the layer
field = "IntegerField1"
group_field = "TextField1"

# read the fc
data = [row for row in arcpy.da.SearchCursor(fc, [group_field, field])]

# iterate over the groups
groups = {d[0] for d in data}
for g in sorted(groups):
    # get the values in that group
    values = {d[1] for d in data if d[0] == g}
    # get a set of the complete range
    complete_values = set(range(min(values), max(values)))
    # the difference between these sets are the missing numbers
    missing_values = complete_values - values
    print("Missing values in group {}: {}".format(g, sorted(missing_values)))

[MAMDOUHZALAKY]

Thank You Very Much For Your Great Solution