Hi Esther,
On Wed, Sep 1, 2010 at 13:29, Nally Kaunda-Bukenya <nkau...@yahoo.com> wrote:
> #THE PROGRAM:
> import arcgisscripting
> gp=arcgisscripting.create()
> gp.Workspace = "C:\\NPDES\\NPDES_PYTHON.mdb"
> fc = "Outfalls_ND"
>
> try:
> # Set the field to create a list of unique values
> fieldname = "OUTFALL_ID"
>
> # Open a Search Cursor to identify all unique values
> cur = gp.UpdateCursor(fc)
> row = cur.Next()
>
> # Set a list variable to hold all unique values
> L = []
>
> # Using a while loop, cursor through all records and append unique
> #values to the list variable
> while row <> None:
> value = row.GetValue(fieldname)
> if value not in L:
> L.append(value)
> row = cur.Next()
> row.SetValue(Tot_Outf_Area, sum(row.AREA_ACRES)) #total area of
> each outfall=sum of all area 4 each unique outfallid
> cur.UpdateRow(row) #to commit changes
> row=cur.Next()
> print row.Tot_Outf_Area
> # Sort the list variable
> L.sort()
>
> # If a value in the list variable is blank, remove it from the list
> variable
> #to filter out diffuse outfalls
> if ' ' in L:
> L.remove(' ')
>
> except:
> # If an error occurred while running a tool, print the messages
> print gp.GetMessages()
Have you tried running this code? I suspect it won't work at all --
and because you are catching all possible exceptions in your
try...except, you won't even know why. Here are the things that I'd
suggest, just from glancing over the code:
- Remove the try...except for now. Getting an exception, and
understanding why it occurred and how best to deal with it, is IMHO
very helpful when prototyping and debugging.
- Take another look at your while loop. I don't know ArcGIS, so I
don't know if the UpdateCursor object supports the iterator protocol,
but the normal Python way of looping through all rows would be a for
loop:
for row in cur:
# code
For example, you are calling cur.Next() twice inside the loop -- is
that what you want?
Hope that helps,
Rami
>
>
>
> #Please Help!!!
>
> #Esther
>
>
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
>
--
Rami Chowdhury
"Never assume malice when stupidity will suffice." -- Hanlon's Razor
408-597-7068 (US) / 07875-841-046 (UK) / 0189-245544 (BD)
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