Getting attribute table using Python in arcgis 10

[SreenivasaRaoPigili]

Hi,
   I am new to python scripting. Can anyone pls help me on the below query.
1.I have one MXD, which contains 10 shapefiles.
     ---- i am able to access these shapefiles using arcpy.mapping.listfeatures(mxd).
2.Based on the shapefile names, i have to access the different colmns in the attribute table.
    ---- Here i am unable to access the layer attribute table.
    ----- by using arcpy.listfields(shapefile), i am trying  to get the column values. But i am getting some object references.

[JosephArmbruster]

I'm not sure if the behavior is the same in 10 but in 9.3 the fields returned by the listFields method are field objects.  You can access their name and type using the .Name and .Type members.  Here is a short example:

fields = gp.listFields(shapefile, "*", "ALL")
for field in fields:
   print field.Name, ' : ', field.Type

[DarrenWiens2]

If you want to access the actual cell values in the columns, use a cursor (like a SearchCursor).

[SreenivasaRaoPigili]

Hi,
   Thanks for giving reply. Now the issue got resolved.
Currently I am facing one more issue.
Actually I have two lists. let us say, listA = [1,2,3,4,3,2,1] and listB = [7,8,9,5,4,3,1]. Here have to get output like below.
in listA, we are getting value-1 in 2 indexes. I have to sum the values from listB in those positions.
Finally I have to output like below.
sum of 1's is ----7+1=8
sum of 2's is ---8+3=11
sum of 3's is----9+4=13
sum of 4's is----5

can you please help on this task.

[BruceNielsen]

You can accomplish this by using a dictionary. Here's some code:

dict={}
for x in zip(listA,listB):
    if x[0] in dict:
        dict[x[0]] += x[1]
    else:
        dict[x[0]] = x[1]
newListA=dict.keys()
newListB=dict.values()

[DarrenWiens2]

There are many ways to do this (check here for an intro to lists), but I would start by making a loop to go through the list, a counter to keep track of the index position, and using the list.reverse method to flip the list. Add the current index value to the flipped index value.

Edit: Correct me if I'm wrong, but in your example you're adding the first to last value, second to second-last, and so on...

[JakeSkinner]

Are you trying to Sum the two lists together based on the index of each list?

Ex:

listA = [1,2,3,4,3,2,1]
listB = [7,8,9,5,4,3,1]

index[0] = 7 + 1 = 8
index[1] = 8 + 2 = 10
index[2] = 9 + 3 = 12

If you are, you can use the following code to do this:

import os

listA = [1,2,3,4,3,2,1]

listB = [7,8,9,5,4,3,1]

listC = []

x = 0

while x < len(listA):
    listC.append(listB + listA)
    x += 1
                 
print listC

[SreenivasaRaoPigili]

Hi All,
    Thanks for yours quick response.  Thanks Bruce Nielsen. yours approach is solving my problem.