Adding values from list to field in feature class using ArcPy?

Question

I have the code below. fc is a shapefile. I add a new field called "RANK". I want to populate the RANK column with values from Final_Rank list. Fortunately, they are of the same size. Field RANK has got 11 rows and Final_Rank has 11 values. The code below creates the field RANK and then adds 11 additional rows, below the existing 11 rows in the attribute table and inserts the values to RANK beginning notfrom the start but from the 11 additional rows. I want the code to add the values to the existing RANK field without adding any rows.

print Final_Rank

arcpy.AddField_management(fc, "RANK", "Double")

with arcpy.da.InsertCursor(fc, 'RANK') as cursor:
    for i in Final_Rank:
    cursor.insertRow(i)

Answer 1

You should be using UpdateCursor instead:

print Final_Rank

arcpy.AddField_management(fc, "RANK", "Double")
pointer = 0
with arcpy.da.UpdateCursor(fc, 'RANK') as cursor:
     for row in cursor:
         row[0] = Final_Rank[pointer]
         pointer += 1
         cursor.updateRow(row)

Answer 2

Insert Cursor is for adding new rows:

InsertCursor can be used to add new rows.

From what i understand you dont want new rows. You want to populate the new field RANK with the values in list Final_Rank. For this you should use the Update Cursor:

UpdateCursor establishes read-write access to records returned from a feature class or table.