Field calculators (available in QGIS, ArcGIS Desktop, etc) can recalculate the values of a single field on all, or selected, records within a table using an expression.

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same or similar search word with field calculator

I am using arcgis 10.1 I have two tables A and B need to find attributes of table B data are on the table A I'm doing a join between table A and B now I want to use the field calculator via a script ...
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48 views

How to use QGIS field calculator to delete style code?

I am struggling with following issue: How to delete style code before id codes x.x.xx.. and the }s in the end? Examples below. Any help appreciated! {\fArial|b1|i0|c0|p34;A.B.11} ...
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558 views

Why does Field Calculator say failure during processing, check geoprocessing results window for details? [duplicate]

I am using the Field Calculator and keep receiving the following error: 'There was a failure during processing, check the geoprocessing results window for details'. I am not very tech-savvy but I have ...
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220 views

Field Calculator - replace string function - data value recognised as a column and is “not found” [closed]

I have the same challenge as GrahamD - Field Calculator - replace string function I have exactly the same challenge. Exactly the same as GrahamD's challenge, p abbreviated for pan. Type_2 as a test ...
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237 views

Arcpy CalculateField using formatting syntax

I have 2 feature classes (FC) that I am merging together and then performing some field calculations on. The 1st FC has 100k+ records in it, and the second FC is a blank FC that I'm using as a ...
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219 views

Field Calculate with a function written in python within a larger python script

I'm writing a python program where I need to field calculate using a python function. The function takes two strings; one used for an if statement and the other to become an integer complete a simple ...
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312 views

Why does CalculateField set values to <Null> when output extent is in a different coordinate system?

I'm quite new to ArcGIS, and now I have to work on a script that goes through a list of feature classes to: add a field to their attribute table and fill that field with a number that I retrieve ...
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2k views

How to search text string and select item in QGIS?

I have a table attribute with complete roads name. I have to search items by digiting a part of the road name and I need to colour all the items selected. eg: ROAD NAME: / road 01 / road 02 / road 11 ...
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124 views

Trying (+ failing) to use a Function in Field Calculator

I'm trying to populate a field using a function. When I run this in Pyscripter, it works fine: d = {} # Function # def find_dups(val): d[val] = d.setdefault(val, -1) + 1 return d[val] # ...
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834 views

How to calculate polygon areas in acres or square miles instead of feet?

I have a layer in State Plane NAD83. When I use "Vector|Geometry Tools|Add/export geometry columns" or Field Calculator they both create the area in feet. What if I want acres or square miles? Thanks ...
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552 views

How can I easily detect gaps in a polyline using arcmap 10.0 (arcview license)?

I'm making routes by selecting links from a streets layer which I export as a new temporarely layer in arcmap 10. This layer which I call route_temp unfortunately can be very long and contain gaps, ...
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359 views

Add sequence numbering based on attributes in a table [duplicate]

Is there a way to auto populate a sequence of numbers based on another attribute in a table? For example, if field "Name" has a sequence of numbers from 1 to 10, and I want to number all the rows in ...
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2k views

Replacing NULL values in geodatabase table?

How do you update NULL values within a geodatabase table using the ArcGIS Field Calculator (service pack 4) without changing other values to NULL? I've tried the suggestions on this previous ...
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366 views

Error when using .isalnum in ArcGIS fieldcalculator

ArcGIS keeps throwing an error when I use the following script in the field calculator, using Python: pre-logic script code: y= () if !fieldx!.isalnum(): y= 1 else: y= 0 Fieldy= y The ...
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34 views

Concatenate Multiple String Fields and Convert to Date field using ArcGIS Field Calculator?

I'm Working in Model builder using the calculate value tool. I have three columns - SignatureDay, SignatureMonth, SignatureYear - All three are string data types and all consist of just numbers for ...
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53 views

Building heights above DEM through field calculator

I have a series of building polygons which I would like to convert to a raster illustrating their height. I have the building heights but not their elevation above sea level datum. I have the ...
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124 views

Writing Python script in Field Calculator in ArcGIS Desktop?

I'm a programmer, I have programmed in C#, Java, but not with Python. And I'm not a geographic worker. How can I write a python script into Field Calculator to be able to check the other column value. ...
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118 views

Painfully slow performance with Join and Calculate Field

I have a point layer and a table with approximately 100 fields. I need to join the table to the point layer based on a key field and create a new shapefile / feature class. This script has been ...
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120 views

How to calculate cumulative decreasing sum in ArcGIS-10.2

I need to calculate the cumulative decreasing sum as a field in a rasters attribute table. The cumulative decreasing sum is the accumulation of the last values to the first, so it is basically the ...
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52 views

Field Calculator not showing some fields

When I open my attribute table, click on a column, and select Field Calculator it opens and doesn't list all of the Fields in my attribute table. Why can't Field Calculator find these Fields?
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73 views

What is the syntax for Python 2.7 to permanent display in percent in a field column?

What is the syntax to build to calculate field, for example, Acres to Percent? 841173.00 to 82 % What I want the field column in Percent to be display numbers with percent with the alignment to ...
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36 views

Interaction with two variables as parameters, saving the raster properties output into a table (.dbf)

The draft of the model below TASK: I need to calculate the percentage of river channel that is covered with shadow in each timestep RESOURCS: I have values for azimuth and elevation of the sun ...
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166 views

Replacing attribute table entries using python script. Script needed

I am using ArcMap 10 from ArcGIS 10.2.1 package. I got an attribute table, with few collumns. I need to replace some column "String_A" entries with newer "String_B" entries, in the same row. In both ...
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102 views

How to calculate/record attachments' file names using Field Calculator?

I have a point feature class containing attachments corresponding to jpg files (sometime more than one jpg per feature). I would like to use the "field calculator" to calculate/record a new field that ...
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127 views

QGIS: graphical-modeler to calculate area of polygons

I'm trying to calculate the area of polygons using the field-calculator in QGIS (2.0.1). If I do this manualy it works fine, but if I do this using the graphical-modeler I get NULL as area for every ...
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1k views

how to use the TRIM function in field calculator

I need to remove leading spaces in a field in my attribute table, but not how to do it from the field calculator
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152 views

CalculateField_management - updating fields with X and Y coordinates for start and end of line

I've searched all the help documents and can't see where my script is going wrong. I've tried adding the fields as FLOAT, replacing "PYTHON_9_3" with just "PYTHON" but it just doesn't work. The ...
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138 views

ArcMap Calculate Field..if “text” in !Field!

Is it possible to use Field Calculator in ArcGIS to add text to a new field based on an if in statement? Example: In an attribute table I have a some fields called !X!, !Y!, !Z! where "A (xx%)", "B ...
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37 views

Wich is the way to create serial field following alphabetical order with QGIS?

I have a field with names, a string field, and I want to create another one with serial content following the alphabetical order. I have this: -------- |Field1| -------- | B | -------- | C ...
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395 views

Field calculator error and Geoprocessing results window empty

I need to use the field caculator for a new field that I have just added but I keep getting the following error: The problem is that when I open the Geoprocessing Results window is just completly ...
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89 views

Can QGIS report/calculate areas/perimeters of individual polygon components within multipart shapefile?

Can QGIS report/calculate the areas/perimeters of individual polygon components within a multipart shapefile without using the "explode" vector tool to generate a new file? using QGIS 2.2.0 on ...
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113 views

Is it possible to calculate a value based on values of another row?

I have a point shape file in qgis. For one of the attributes, I would like to offset the values, i.e. the value for point 1 goes to point 10, the value for point 2 goes to point 11 and so on. I see ...
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350 views

Conditional Calculation of a text Field Value Based on antoher text field value ArcGIS10.1 [duplicate]

I Created a new field to explain some zoning codes in an attribute Table. I basically want the new field "Zone" to have a string value based on the field "Zoning" For example if the "Zoning" field ...
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165 views

Problem in calculating length

I am Digitizing road line in India using open layer plugin.When I calculate the length of line using field calculator it gives me the result in millimeter . I thought it is the projection problem and ...
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242 views

Python: using CalculateField_management for duplicating attributes with a double quotation mark

I am writing a python script which duplicates a field. The field contains names of pipelines but some of these names has double quotation (ex. 8" NGL PIPELINE). I have created a new field and trying ...
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163 views

How can I calculate different polygons by different attributes?

I'm doing my master thesis and want to calculate different polygons (in QGIS 1.8 for Mac) in four different columns which I defined by different attributes. i.e. some of the attributes in the first ...
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77 views

Table calculation in QGis

I have a shape file with the attribute "yield". I need to know the math difference between yield (id1) and yield (id2)...then yield (id2) and yield (id3) and so on... I hope you understand what I ...
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289 views

How to calculate the area of the convex hull of a points layer

I have a shapefile in QGIS that I have created by importing a CSV of points, using Points2One to convert to a shapefile and then importing the shape. I am now trying to calculate the are of the shape ...
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126 views

Stacking attributes in a text field

I am trying to stack my text in an attribute table using the field calculator, but it does not seem to be working. My field name is: Facilities. My attributes are in this format: Public ...
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172 views

FieldPyculator Plugin - How to concatenate fields?

How can i concatenate two fields using pyculator plugin? There is any document with all pyculator functions that i can use in "field expression"?
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2answers
901 views

How to auto populate multiple fields in attribute table?

i have Feature Class Buildings, it has many fields like ...
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680 views

Null output from field calculator code block

I have a simple calculation to compare two columns and populate a new column with the lower value but I am getting null output...any ideas? expression ...
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22 views

How to use calculatefield_management with ArcPy and joined second table? [duplicate]

How can I use calculatefield_management with ArcPy if I have a joined second table? I want to go through the attached table's field and I want to get records where the certain fields is. How can I ...
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22 views

How to use random number generator to select by attributes in ArcMap? [duplicate]

I am not familiar in using Python and random number generator. I was wondering how to select 250 rows/values from a column named "JUROL". Every value in that column is different and the column ...
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32 views

How do I auto-populate more than one other attribute field with values based on the value of another field within the same record?

Based on value selection from one attribute field, would it be possible to auto-populate many fields within the same record with predefined values either from a range of values within another field or ...
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33 views

Many ELSE statement in Expression in QGIS (2.6) [duplicate]

is it possible to have more than one ELSE in the CASE WHEN statement in the Expression builder in QGIS? For example: CASE WHEN "population" > 5000 THEN 'big' ELIF WHEN "population" > 1500 THEN ...
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27 views

Copying the numeric portion of an address to a new field

I'm attempting to copy just the numeric portion of a street address into a new table using the Field Calculator in QGIS. The expression I'm trying to use is: left( "SITE_ADDR", strpos( "SITE_ADDR", ...
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21 views

Python script to get count of features that meet a certain criteria [duplicate]

I am in search of a Python script for use in the ArcGIS Field Calculator to return the number of features that meet a certain criteria. Here's where I am getting stuck: def ...
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102 views

Python script to get feature count in a feature class that fall in a specific range

I need to write a Python script to be used in the ArcGIS Field Calculator that will return a feature count for values between a range defined by the values in two other columns. Here is a graphic ...
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31 views

Is there a way to automate field calculations for ArcGIS Server?

I have a field that I'd like to be concatenated with each new objectID when a feature is created in my feature service. Workflow: Feature added, already contains objectID. Would like my Service ...