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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What's wrong with this VB Script code for the field calculator in ArcGIS 10?

I am trying to use one field's contents ([Condition]) as a condition for populating another field ([Intact]). I try to run the following code in the Field Calculator, but it never works (and is not ...
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185 views

ArcMap Python Question: Trying to Field Calculate Slope Percent in to Text

I have a layer of polygons that I spatially joined to a raster to point layer of slope percents. My polygons now have the percent of slope in a field called Avg_point. I want to use the field ...
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1k views

How to use QGIS field calculator in python?

I would like to use QGIS Field Calculator in Python to update the existing column based on certain conditions? How can I do this?
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497 views

Syntax error from Python parser of ArcGIS field calculator if then?

Using ArcMap - I would like to calculate one field based on the value of another field. I want to Update the field 'Date_Class' based on the value in another field 'MIN_YEAR_B'. I was trying to do ...
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1answer
319 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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266 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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85 views

How to populate new field according to string content of another field using VB script?

I want to populate a new field called Letting according to the string value found in another field. If 'ASP' or 'Q' is in field ExternalRE then I want 1 in Letting, everything else to be 0. Here is ...
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243 views

ERROR 000989 Issue with Python Script and Field Calculating distance between two long lat points

very new to scripting and I have been struggling with my script for a while. I'm not sure why it doesn't work in field calculator. I am trying to calculate a list of distance between two long lat ...
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1answer
90 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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1answer
126 views

What is the expression for getting a subset of characters in QGIS Field Calculator?

I have a column of 10 character names e.g. L3NAM1988K. How can I delete the first 5 characters and the last 1 character using an expression in the QGis Field Calculator?
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1answer
78 views

Use value of Field in Calculation in Modelbilder

In Modelbuilder I have set up a model, where in one step I do a "Calculate Field" like "round((!OID!-1- %MyField% /15)/452,1)+1" . For the calculation i use the value of %MyField%, which actually is ...
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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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1answer
375 views

Is it possible to have auto-updating area fields?

I'm using QGIS 2.4.0 and I've noticed some problems with the derived area and the $area field. Firstly, I have a polygon which is a filled ring, inside another polygon. The derived area, and therefore ...
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139 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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1answer
670 views

Calculate field in model builder using file name

I have browsed answers to similar questions but I still cant figure it out. I have created a new field called "namemonyr" in all of 646 shapefiles. I now want to populate that field using ...
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1answer
158 views

Add or subtract days to date field using the field calculator

I am using ArcGIS 10.1 I'm not a programmer I want to use the field calculator to add 4 days to the current date if the status is "delivery" or subtract 5 days if its status is "order" this ...
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1answer
412 views

QGIS field calculator expression: selecting min/max values within field groups

I am new to using QGIS (previously used Arc) and trying to get my head round the expressions and Python. I have series of polylines representing routes and require the linear distance from the ...
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1answer
241 views

How to calculate distances in QGIS field calculator?

So I'm using qgis 2.6.0 and I have a csv (converted into a .shp) with two geometry columns, I want to create a new column with the distance between the two geometry: shot.lat shot.lon haul.lat ...
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1answer
122 views

Converting Aspect degree to westness

I have extracted Aspect values in degree from DEM in ArcMap 10.2 full license. I want to investigate effect of Westness in my model so I was using conversion formula of Folded Aspect : ABS (180- ...
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216 views

Using Field Calculator to append attribute

I have a field containing the file names for photos. I need to add the folder location to the beginning of each file name. Anyone know the code for doing this in Field Calculator?
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1answer
339 views

Calculate value from an equation using Field Calculator Python/VB Script

I wanted to calculate a result value from 3 fields using an equation. VBScript or Python codes are also accepted..:-) the equation is RESULT= [(R^2/3)(S^1/2)]/n..
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1answer
409 views

Using if else statement in Python Parser of Field Calculator in ArcGIS for Desktop?

I need help in writing the python script in the field calculator. I have three fields namely: CODE COMPLEX Map1 Map1 is an empty field that I want to populate. I have a number of conditions to cater ...
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3answers
204 views

Field Calculator - How to evaluate and sum multiple fields?

I'll do my best to describe the problem - my main issue isn't so much the python code but rather the logic I'm using. The file I'm working on is a polygon shapefile with forest attribute data. In the ...
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255 views

Calculate Field based on two fields using python

I'm trying to calculate new values for a field based on two other fields. In VB I don't have any problem, but I need to use python to publish my gp service.
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1answer
720 views

How to create a Qgis python script to manipulate fields with some parameters?

I'm just beginning with QGIS. I have a shape file with 10 fields field1, ..., field10, and many thousands of data. I will like to automatize the next sequence (in a python script or a model): load ...
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1answer
57 views

Categorizing GPS data based on cumulative time using ArcGIS Desktop?

I have GPS data which includes “Lon”, “Lat”, and cumulative Time from 0 (sec) as fields. I want to add an integer variable new field, “Trip,” which starts from zero, and is incremented by one after ...
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How to add column to attribute table using field calculator with $length function?

I used the following code to add a separate column to the attribute table with the length of features. from PyQt4.QtCore import QVariant from qgis.core import QgsField, QgsExpression, QgsFeature ...
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1answer
310 views

Remove Leading Zeros with QGIS Field Calculator

I'd like to take this attribute value: "MAP_PAR_ID": "0160011000", and populate a new field with "16-11". This works: concat(substr("MAP_PAR_ID",0,3), '-', substr("MAP_PAR_ID",5,3)) but i need to ...
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76 views

Using Field Calculator to fill out a list of unit numbers

I am adding address points for individual units in trailer/RV parks and I would like to be able to use the Field Calculator to assign the unit numbers. Is it possible to tell the Field Calculator a ...
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1answer
118 views

count how many times an attribute is repeated, using “field calculator”

I'm using Arcgis 10.2.2 there is a way to count how many times an attribute is repeated, using the "field calculator" to make a selection after example of repeating more than 20 times
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1answer
71 views

Referencing fields in code block of Field Calculator in ArcGIS for Desktop?

I'm trying to use values from a field to fill a new field with a truncated version. The 'str.rindex' function is working out well, but I can't seem to figure out how I'm supposed to reference the ...
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Field Calculator QGIS: CASE WHEN [duplicate]

at first, sorry for my English. I'm using Google translator. I have a .shp file with attribute table. Like this... -- A -- -- B -- -- C -- QString Double Double Data ...
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88 views

Averaging XY data for locations in QGIS

I wanted to find out mean of the selected point using QGIS. I tried out selecting using attribute table but could not find an option for mean in field calculator. I have attached a screenshot with ...
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209 views

Field Calcuator to add percent using Python

What might I go wrong here is that I am trying to add percent. I use the Field Calcualtor and it keeps getting an error. I am opening the Table to add a field named Percent and then type this: ...
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1answer
115 views

How to work with accentuated strings in Python scripts in ArcGIS Desktop Field Calculator?

` pre-logic: def myCalc(name,nameVal): if (name == nameVal): return 1 else: return 0 var_name= myCalc(!Epulettipus!,"Lakóépület") ` This doesn't work with accentuated strings. (But ...
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2answers
627 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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1answer
101 views

Concatenate fields value excluding empty values

I need to concatenate the value of two fields excluding empty values, using Field calculator. The fields are: AREA_HI and AREA_LO I have tried using a Python script but ArcGIS returns an error ...
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1answer
62 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 ...
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1answer
761 views

Slow performance with Add 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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1answer
889 views

ArcGIS 10.0, Field Calculator Nested “if” statement with strings

I need to assign a value depending on other two columns "FNP" and "Teilort". I wrote this script in phyton for field calculator. It actually works (no error messages) but the results in every cell is ...
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0answers
113 views

Geometric functions in field calculator in QGIS

I had a look in the manual of QGIS and I also browsed the Internet to find some useful information about the geometric functions of the field calculator. I've found this post but I'm still confused. ...
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1answer
436 views

Finding distance between consecutive points using ArcGIS Desktop?

I am wondering how I can get the distance between consecutive GPS locations in ArcMap 10 (i.e. the distance between consecutive GPS locations sent in during a wildlife telemetry study).
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How to delete last part of a string starting from the 1st non numeric character? [closed]

I'm looking for a Python or VB statement to remove the last part of a string, starting where the 1st non Numeric character appears, using the Field Calculator in ArcMap 10. Here's an example of what ...
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2answers
363 views

Iterate calculate field in multiple tables in ModelBuilder

I would like to iterate calculate field in multiple tables using ArcGIS Model Builder. The figure below explains details of the calculations. My existing model calculates value only for the first ...
2
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2answers
114 views

How to handle “Error: Town not found” when updating an existing field with Field Calculator?

I want to update a field in field calculator. update existing field is checked. Column to be updated : Column2 CASE WHEN "COLUMN1" IS NOT NULL THEN "COLUMN2" = "Town" ELSE ...
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3answers
350 views

How to flip, or invert attribute tables with respect to row ID arcgis

I need to invert the fields of an attribute table relative to the row ID field. As a very simple example of what I need; if the row IDs of 1, 2, and 3 corresponded to identical values in another ...
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2answers
4k views

How to replace “NULL” value with Zero in geodatabase table

I am having some difficulties to change "NULL" values to zero in geodatabase. I have tried the following python code in ArcGIS 10.1 ("Field Calculator") to change it but did not work. Pre-Logic ...
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2answers
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ArcGIS Field Calculator passes European-formatted floats as tuples

I have the problem that the ArcGIS Field Calculator doesn't read a float number when it is included in Python by referring to the field that contains it, in this way: def giveResult(floatValue): if ...
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378 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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2answers
106 views

Returning value from other field, using FieldCalculator

I am very new to Python and need what I believe is a very basic script in order for my field to represent another fields' input, if the field's value is 0. I tried to search for this, but gave up ...