Python scripting (update cursor, extract previous row values)

Question

I am new to Python scripting.
I would like to use SearchCursor to iterate in each row using the FID as index. Then I would like to evaluate length based on the following conditions:

If the length >100 then (CAT remains at 0) and proceed to next row.
If the next length is less than 100, then it should go back to the previous (immediate) row (that has a value of >100)  and extract values in that row (FID, Length, CAT), and save them in an empty table, then the script should stop there.

fields = ["FID", "Length","CAT"]

with arcpy.da.SearchCursor(fc, fields) as cursor:

for row in cursor:
        if row[1] > 100:    
           print (row[2])        
    
        elif row[1] < 100:
           #Some code accessing the previous row here
           print (row[0], row[1], row[2]) #to test what is to be printed

BERA · Answer

A little bit convoluted but it works:
import arcpy

tbl = r'C:GISdata.gdbtbl'
data = [row for row in arcpy.da.SearchCursor(tbl, ['OID@','length','CAT'])] #List all rows
#>>data
#[(1, 180, 0), (2, 179, 0), (3, 168, 0), (4, 141, 0), (5, 129, 0), (6, 125, 0), (7, 115, 0), (8, 70, 0), (9, 51, 0), (10, 16, 0), (11, 3, 0)]

for row1, row2 in zip(data, data[1:]): #For each pair of rows
    #print(row1, row2)
    #(1, 180, 0) (2, 179, 0)
    #(2, 179, 0) (3, 168, 0)    
    #...
    if row1[1]>100 and row2[1]<100:
        the_one = row1[0] #If true then store objectid as the_one variable
        break #No need to keep iterating after it is found
#>>the_one
#7 #My objectids start with 1
tbl_out = r'C:GISdata.gdbtbl_out'
oidfield = arcpy.Describe(tbl).OIDFieldName
sql = "{0} = {1}".format(arcpy.AddFieldDelimiters(tbl, oidfield), the_one)
arcpy.MakeTableView_management(in_table=tbl, out_view='result', where_clause=sql)
arcpy.CopyRows_management(in_rows='result', out_table=tbl_out)

Python scripting (update cursor, extract previous row values)

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