2
votes
2answers
54 views

What is the most efficient method to iterate geoprocessing operations through an attribute table?

I want to calculate the clipped raster layer percentage for a shapefile consist of overlapping polygons, since ArcGIS doesn't support tabulate area for overlapping features, so I used a loop to ...
0
votes
1answer
51 views

How to automatically generate least-cost paths between several polygons?

What is the fastest way to automatically generate least-cost paths (LCPs) between several polygons with ArcGIS ? I created a python program to do this by using the functions "CostDistance" and ...
12
votes
2answers
310 views

How is the data access cursor performance so enhanced compared to previous versions?

The data access module was introduced with ArcGIS version 10.1. ESRI describes the data access module as follows (source): The data access module, arcpy.da, is a Python module for working with ...
2
votes
3answers
125 views

Iterating using search cursor and layer selection performance?

I'm trying to use the results of a search cursor to iteratively make selections on a feature class and then create new feature classes (so you get a new feature class or shp for each unique value in a ...
5
votes
2answers
157 views

Creating numpy.array with variable number of fields to test arcpy.da.ExtendTable performance?

There was an ArcPy Café blog posting entitled Adding Fields: Performance Tips which advocated: Two approaches to help increase performance when adding numerous fields to a table or feature ...
4
votes
2answers
169 views

How to transfer attributes to thousands of local points from ArcSDE feature class with millions of polygons?

I have a set of points and a huge feature class with topographic information (OS MasterMap for who knows it). I'm talking millions of polygons huge. I want to transfer attributes of the polygons to ...
0
votes
0answers
96 views

ArcMap: Append is really slow

I'm writing a Python script for ArcGIS 9.3.1 which is supposed to do the following: Create a new feature class in local FGDB Loop over a set of IDs (~40,000) Select features from an Oracle GDB with ...
3
votes
1answer
193 views

IO Performance of ArcPy in virtual machine

The following script just copies a file into RAM, performs some simple operations and writes the result back to hard disc: import arcpy import random import time arcpy.management.Delete("in_memory") ...
1
vote
0answers
81 views

Why might ArcPy, TableToTable, MakeQueryTable and ArcSDE have performance issue in IDLE?

I have written a Python script tool to do: Make Query Table Table To Table (with fieldmapping). The code is nothing more than arcpy.MakeQueryTable("table1;table2;table3", ...
8
votes
1answer
168 views

Difference between python window and toolbox

Are there differences in performance or other potentially critical area between running a python script in the python window versus running it from the toolbox in ArcGIS 10.0? I am asking in cases ...
2
votes
1answer
162 views

Clipping buffers to census tracts

I have donut buffers generated to protect anonymity of household locations. They need to be clipped so that they are only inside the census tract that the original point was in. The code takes about 8 ...
5
votes
2answers
872 views

How to improve Python script processing speed (performance)?

I've been working on a script which essentially reads in a large amount of point and polygon data and generates frequency values for a featureclass of 2.5 acre hexes covering California. I have found ...
11
votes
1answer
2k views

Fastest way to count the number of features in a feature class?

With the introduction of the Data Access module in arcpy (30x faster search cursors), I want to know if counting features matching sql criteria is faster than the traditional MakeTableView + GetCount ...
5
votes
3answers
907 views

arcpy taking longer and longer in a loop

I am looping through an amount of point arrays, creating data on the fly. The features/arrays, are largely similar in size. One thing I have noticed, is that when I start the process, the time it ...
27
votes
4answers
3k views

Performance of ArcGISScripting and large spatial data sets

I am currently writing a python script using the arcgisscripting module to process a reasonably large data set (~10,000 records in total) normalised over a small number of tables, 8 in total. The ...