Determining Min/Max values from feature class using ArcPy?

Question

I am very rusty/inexperienced in Python.

I would like to create a more compact script that prints min and max values of each numeric field from a feature class. Right now I have the code below repeated for each field that contains numeric values.

How would I code this to identify if a field has numeric values and then print the min and max values to the python shell or even better to a .csv/text file?

import arcpy
data = "C:/Workfolder/Input.gdb/FeatureClass"

listname = []
cursor = arcpy.da.SearchCursor(data, "field1")

for row in cursor:
    listname.append(int(row[0]))

print 'Field1_min, {0}'.format(min(listname))
print 'Field2_max, {0}'.format(max(listname))

fatih_dur · Answer

I think one of the efficient options would be using where and sql_clause arguments of arcpy.da, for example:
field_to_find_min_max = "MyFieldName"
min_value = arcpy.da.SearchCursor(data, field_to_find_min_max, "{} IS NOT NULL".format(field_to_find_min_max), sql_clause = (None, "ORDER BY {} ASC".format(field_to_find_min_max))).next()[0]
max_value = arcpy.da.SearchCursor(data, field_to_find_min_max, "{} IS NOT NULL".format(field_to_find_min_max), sql_clause = (None, "ORDER BY {} DESC".format(field_to_find_min_max))).next()[0]

This also makes sure the only non-NULL values are processed (where clause).

Michael Stimson · Answer

Using the list is clever, or at least it seems until you get to a very large feature class. Instead of the list:

import arcpy
data = "C:/Workfolder/Input.gdb/FeatureClass"

cursor = arcpy.da.SearchCursor(data, "field1")

FirstRecord = True

for row in cursor:
    if FirstRecord:
        FirstRecord = False
        MinValue = int(row[0])
        MaxValue = int(row[0])
    else:
        MinValue = min(int(row[0]),MinValue)
        MaxValue = max(int(row[0]),MaxValue)

print 'Field1_min, {0}'.format(MinValue)
print 'Field2_max, {0}'.format(MaxValue)

Or using Summary Statistics:

import arcpy
data = "C:/Workfolder/Input.gdb/FeatureClass"
arcpy.Statistics_analysis(data,r"c:WorkFolderInput.gdbStatTable",[["Field1","min"],["Field1","max"]])
cursor = arcpy.da.SearchCursor(r"c:WorkFolderInput.gdbStatTable",["Field1_min","Field1_max"])
row = cursor.next()
print "Field1 Min = %s, Field1 Max = %s" % (str(row[0]), str(row[1]))
del row
del cur
arcpy.Delete_management(r"c:WorkFolderInput.gdbStatTable")

Be careful that field1 is, or can be converted to, an integer. If it's a date or string field you're gonna have problems!

Stephen Lead · Answer

Another way to calculate the minimum is to use the SummaryStatistics function.
To iterate through the fields, use the ListFields function:
# Create a list of fields using the ListFields function
fields = arcpy.ListFields(feature_class)

# Iterate through the list of fields
for field in fields:
    if(field.type == 'Integer' or field.type == "Double"):
        #calculate the minimum using SummaryStatistics

Determining Min/Max values from feature class using ArcPy?

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