Using Field Calculator to summarize range of values?

Question

I am fairly new to ArcGIS and GIS operations.

I am trying to use field calculator to summarize a range of values having different FID_xyz. For example

I have a geo table with the following FID_xyz with their corresponding GRIDCODE.

Now I need to populate a new field ( for e.g AREA_OVERLAP) I added after the FID columns :

I was wondering if someone can help me with a .cal expression to summarize or other operations for a batch of values tied to a certain row. I am somewhat familiar with Python but not accustomed to the ArcGIS environment.

Thank you!

​

KaustavChaudhury1 · Answer

Thank you Darren.

This looks promising.

I am away from my system at this moment. I'll give it a shot!

DarrenWiens2 · Answer

I'm not sure how you do this in the field calculator, but here's how you can do it in Python:

>>> fc = 'points' # change to your feature layer name
... fid_fields = [i.name for i in arcpy.ListFields(fc,'FID_*')] # list of "FID_" fields
... all_fields = ['TOTAL_AREA_OVERLAP'] + fid_fields # add overlap field to beginning of list
... with arcpy.da.UpdateCursor(fc,all_fields) as cursor: # update cursor
...    for row in cursor: # loop through cursor
...        total = 0 # start at 0
...        for i in range(len(fid_fields)): # for each FID field
...            total += row[i+1] # accumulate
...        row[0] = total # store total in first position
...        cursor.updateRow(row) # write row

KaustavChaudhury1 · Answer

Yes. I am trying to find the sum of values for the fields for each row but only the fields that start with "FID_".

About using excel , it only allows 256 columns. Still I exported it to csv and fulfilled my task. But this is just one of the tables out of several and it was getting cumbersome to manage for each tables. Hence I was hoping for a more efficient way to do it in-vivo Arcgis. I saw a number of posts about python expressions that can batch process such operations and was hoping if that is possible for my task as well.

Thank you!