Cursors are used by database programmers to process individual rows returned by database system queries.

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15
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2answers
2k views

Exporting table to XYZ ASCII file via ArcPy?

I'm looking for a way to export an ArcGIS table (created with the Sample tool) to a text file via ArcPy. I can do this in ArcGIS via the context menu by right-clicking the table, but have not found ...
12
votes
2answers
445 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 ...
9
votes
5answers
524 views

How to improve performance when using ArcGIS cursors in Python with big tables?

I have a pretty big point feature class in a file geodatabase (~4 000 000 records). This is a regular grid of points with a 100m resolution. I need to perform a kind of generalization on this layer. ...
7
votes
2answers
1k views

Getting unique value of second field using arcpy.da.SearchCursor?

I have a feature class and using arcpy.da.SearchCursor I'm getting unique values of a field (e.g. Name). How can I use this method to get the associated row value of a different field (diff field = ...
6
votes
5answers
211 views

How to access adjacent rows with cursor?

In the attached screenshot, the attributes contain two field of interest "a" and "b". I want to write a script to access the adjacent rows in order to make some calculations. To access a single row, ...
6
votes
2answers
250 views

What technology is used behind arcpy cursors?

I'm using ArcGIS Server 10.0. I have a geoprocessing using arcpy search, update and insert cursors. I'd like to know more about the technology behind these cursors. Does it use any driver or pool to ...
5
votes
1answer
1k views

Is it possible to sort an arcpy.da.UpdateCursor()?

I have an ArcPy Data Access update cursor that I would like to sort before making updates to it. The cursor makes updates if I don't sort, but if I add a sort to the cursor I get an error, ...
4
votes
2answers
996 views

arcpy.SearchCursor row.var

In arcpy.SearchCursor for row in rows I can return row.fieldname statically, but if fieldname is a variable, I don't know how to return the row.value of that variable dynamically. for example: ...
4
votes
2answers
266 views

Is it a bad idea to convert a File Geodatabase table to a dictionary?

First, what am I trying to do? I am building a Python script that should be called from an ArcMap 10.0 toolbox. This scripts uses (among other inputs) data contained in huge gdb tables. It processes ...
4
votes
3answers
575 views

How to create Where Clause from user input via Python list?

I am trying to perform a query based on values in a Python list. The where clause will then be used in an Update Cursor, so that the rows NOT equal to the values in the list will be deleted. This is ...
4
votes
3answers
981 views

How to extract data using arcpy.da.SearchCursor

I have a shapefile of point features showing fire locations in a given year. One of the fields is named "YYYYMMDD" and indicates the corresponding date that that fire happened. In Python, I am trying ...
4
votes
1answer
110 views

How to add Attributes to a polygon with arcpy

I have a question about arcpy. I want to create a polygon FeatureClass with attributes. The code below is just test-code that generates some polygons for speed testing. I want to add some additional ...
4
votes
1answer
142 views

How to extract certain values from a table using the SearchCursor Tool

I am trying to write a python script to extract certain values from a table: the table I am referring to is a big collection of nitrate values for different water depths, which are deposited in the ...
3
votes
3answers
248 views

Using da.SearchCursor to get count of unique values in a field

Is it possible to use arcpy.da.SearchCursor() to get a count of unique features in a field without a dictionary? So, by this I mean if I have a field called TEXT which contains 10,000 rows populated ...
3
votes
2answers
1k views

Move the cursor backward - opposite of row = rows.next()

I'd appreciate if anyone could please tell me if there is a way to go up one row in python cursor. opposite of row = rows.next() Thank you!
3
votes
1answer
659 views

Arcpy Update Cursor (arcpy.da.UpdateCursor()) not saving changes to 'SHAPE@LENGTH'

Looked around and found other Cursor questions, but nothing dealing with updating 'SHAPE@LENGTH'. I am running ArcGIS 10.2.1 and have a multipoint shapefile that I am grouping into polygons based on a ...
3
votes
2answers
119 views

How to calculate a value based on another field under arcpy.da.UpdateCursor and cursor.updateRow?

I am trying to do a calculations under arcpy.da.UpdateCursor. I want to calculate the values for the records that have FIPS=06037. I want to take the values from "kg" column and populate the new value ...
3
votes
1answer
2k views

Using ArcPy update cursor to replace <Null> value?

I have been combing the help associated with (None) values in arc, and have not been able to solve the following problem: I have a a field with mixed Null and integer values: 0 100 I would like ...
3
votes
2answers
400 views

ArcPy Data Access Insert Cursor not writing geometries to feature class?

I'm running ArcGIS 10.2.1 and am having troubles with the Insert Cursor in the arcpy module. I have an empty feature class in my geodatabase and have created the short script below to try and find the ...
3
votes
2answers
643 views

Using Select By Location to update field in feature class using ArcPy?

I am using Arc 10.1 and I am working on a script that takes a value from a field within one shape file and updates a field in another shape file based on its location. Basically I have smaller parcels ...
3
votes
1answer
30 views

ArcMap Using Python to Rename a Feature Class based on Print Results

I would like to rename a feature class based on the EDITOR and DATE fields. I wrote this code: import arcpy fc = "C:\Users\PythonTesting.gdb\MyFile" f1, f2, f3 = "EDITOR", "DATE", "OBJECTID" ...
3
votes
2answers
1k views

set values in feature class attribute table to null

I've created a point-data featureclass (fc) containing data from a simple .txt file using Arcpy as follows: arcpy.CreateFeatureclass_management(out_path= outPath, out_name= 'fcTest', geometry_type= ...
3
votes
1answer
621 views

Zoom to Shapefile attribute table row feature

I am working with the python code below in ArcGIS to zoom into a shapefile's attribute table row features without selected until the end of table one by one. I am trying to use this code but this one ...
3
votes
1answer
117 views

Copy multiple features in feature class, update field value based on number copied

I have created a field which will indicate the records I want to alter. What I want to do is then cycle through these records, each will contain sum values in a field.Based on the sum I want to copy ...
3
votes
2answers
292 views

arcpy.SearchCursor loops one time but then does not repeat

The part of the script I'm having trouble with is the arcpy.SearchCursor. The cursor runs 1x and then does not re-run. The goal was to re-retrieve the field value and apply it to the image layout. It ...
3
votes
0answers
109 views

Basic arcpy script with cursors running SLOW!

I've got 2 polygons layers (no gaps): IDUs and crops. What I want is to identify the 3 largest crops by % area for each IDU. This seems common enough but I couldn't find a way to do it all using ...
2
votes
2answers
332 views

Use updatcursor to replace values in multiple fields

I have spent a couple days digging through forums here, ESRI help and elsewhere and each variation of the codes I have tried has not worked. As best as I can tell this is due to my attempt to loop ...
2
votes
2answers
586 views

Measure area of a polygon in specific units using ArcPy

I am trying to find the area of a particular polygon (OriginalPolygon, below), and I can do that... But, I'd like it in acres regardless of the original units of the polygon.(Data is coming into this ...
2
votes
2answers
83 views

How do I skip rows with searchcursor based on an interger value

For example, if I have 100 records, and I want to sample 10% of the records. How do I tell the search cursor in arc10 to read the value of the 9th record, or every 10. I tried to do row[0 + count] and ...
2
votes
1answer
185 views

Invalid SQL Error when using InsertCursor on table created using CreateTable

I am trying to write a list of items to a new table in Arc. When I attempt to add a new row to an Arc table, I get the following error: Runtime error Traceback (most recent call last): File ...
2
votes
1answer
423 views

Am I over-complicating adding and then calculating fields? Suggestions for a better way? (Python)

I'm attempting to re-position a question I asked yesterday here. I am starting to think that the way I wrote my code just isn't the best way. Am I overcomplicating things? I know for a fact that ...
2
votes
1answer
218 views

Updating and inserting a field within the same loop

I am working with an empty feature class where I am writing a script to create polylines within the featureclass and attach an associated text value with the polyline. I am using a for loop as noted ...
2
votes
1answer
79 views

Using ArcPy to Read from Excel Spreadsheet to Python Dictionary

How would I go about creating a script that reads a specified excel spreadsheet and places the values in a dictionary? I have read about the xlrd library and how the library in such endeavors to read ...
2
votes
1answer
39 views

arcpy cursor not accepting float(Inf)

I have a vector layer in which I have added some fields of type 'float' using arcpy.AddField_management. I'm performing simple calculations between those fields using update cursors but the problem is ...
2
votes
1answer
107 views

Python Use SearchCursor/InsertCursor to split attributes in fields

I download data daily and create a geodatabase table. Fields: Company, Customers_Active, Customers Total, County, State Example Data {CompanyA,CompanyB}, {141,424}, {1000,3421}, Cook County, ...
2
votes
1answer
154 views

Using the UpdateCursor to change the values in fields added with arcpy.Addfield_management

I am working with some ArcGIS data and trying to add fields using AddField_management. >>> arcpy.AddField_management("huc4","Class","TEXT") I want to populate this new field using the ...
2
votes
1answer
497 views

How to use ArcPy cursor to define each feature sequentially as current selection of layer?

I want to implement a script that runs through each feature of a feature class, zooms to the extent of the feature, sets the scale to 1:5.000 and adjacent takes a picture of the scene. The steps are ...
2
votes
1answer
35 views

Is it possible that ArcObjectsed ITable.Search hits default table version but cursor iterates over the edited current version of the table?

I'm very new to ArcObjects and working on an ArcMap addin. I'm having some trouble with understanding the results I'm receiving from my queryFilter. It seems doing a ITable.Search(queryFilter, true) ...
2
votes
3answers
76 views

How to update the Z value using an UpdateCursor?

I have created the following script to mimic the ArcGIS 3D Analyst tool, FeatureTo3DByAttribute, which creates a 3D copy of a 2D feature class and sets the Z to a specified attribute. import arcpy, ...
2
votes
2answers
78 views

arcpy.da cursor : iteration not started

I am trying to convert cursors written in 10.0 to use the new arcpy.da module in 10.2.1. If I step through the code in debug mode, it steps into the for loop; however, when I attempt to run the code I ...
2
votes
1answer
76 views

Do I need to set arcpy.env.workspace at the beginning of my python code?

I am new to Arcpy and have been doing simple tasks such as AddField_management and updateCursor. However I have been getting error msgs, such as errors 99999 etc. The errors I get are related to ...
2
votes
4answers
587 views

How to take 2 points from One featureClass, create a line between those points, and add the line to a new featureClass (aka Shape File)?

I'm a total noob/beginner in ArcObjects. I'm coding in C#. I want to extract 2 points from a given featureClass, create a straight line between those 2 points, create a new feature class and add ...
2
votes
3answers
559 views

Calculate Area proportional

I have two tables both of them having polygon geometry. Lets consider Table 1 has bigger polygons which overlap over the smaller polygons in table 2.Now I know how to find how many polygons from table ...
2
votes
2answers
403 views

Why cant I use SelectLayerByAttribute_management while a cursor is set

I've been having a problem with arcpy in that the simple line: arcpy.SelectLayerByAttribute_management ("TEMP_LINES") produces this response: Runtime error : ERROR 000358: Invalid expression Failed ...
2
votes
2answers
649 views

GROUP BY clause in the UpdateCursor arcpy.da

I need to specify a "group by" clause for UpdateCursor arcpy.da. From here I found out that it's possible to do using an optional pair of SQL prefix and postfix. But there are no examples and I'm ...
2
votes
1answer
1k views

Incorrect field name resulted in RuntimeError: ERROR 999999 (Also, better code for adding and calculating fields)

This is the bottom half of my code (and it's been edited somewhat to share publicly). The code works perfectly fine when the fieldList has only three fields in it, but when I populate it with all 108 ...
2
votes
1answer
75 views

Mystery duplicate values

I'm using a unique list to populate up to 10 fields for a fc with correct geometry, in an "overloading" manner as you would in excel. I noticed on my first run through I had an "index out of range" ...
2
votes
1answer
304 views

How to read XY, get raster value and then update field?

I've written a script to run through a point layer, using the SearchCursor in the data access module and then read the XY values. Within the with statement, I then use GetCellValue to get the ...
2
votes
2answers
694 views

Field calculator or update cursor?

I have a feature class in which one field (let's call it "Field_A"), as yet empty, is to be populated by the contents of another field ("Field_B") multiplied by a certain number (I'll call it the ...
2
votes
0answers
36 views

Updating Cursor to Include Newly Created Features

I am using ArcMap 10.1 and python to create cursor that starts at the one and only row of a polyline shapefile, some code runs to create a new feature based on the position of the exisiting feature, ...