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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using mod() with IF THEN field calculation

I am trying to use the field calculator to assign a "odd" or "even" value to a field of small integers. I usually do this with by selecting where: MOD([field],2) = 0 and then just calculating it ...
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592 views

Moving “last name” from last to first in Attribute Table of ArcGIS Desktop?

How do you get e.g. "John D. Doe" to "Doe, John D." in the AT using VB Scripting without going individually going through each line? I am using ArcGIS 9.3. I should note that not all the names are ...
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Find and Replace expression needed in Field Calculator ArcGIS 10

Looking for the Field Calculator code (Python preferred) to replace the last numeral values in a field using another field's values for entire attribute table. Please see screen shot here:
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539 views

Calculating file name with field calculator

Is it possible to calculate the file name in an attribute table? My shape file has a name like "cities.shp". In this shape file I want to have a attribute "cities").
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1answer
647 views

How to add attribute data up?

Sorry if this question is too simple/easy for you guys, but I'm still learning QGIS and pretty much teaching myself where I can. Is there a way to add data from 2 columns into one new column inside ...
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Why is ICalculator.Calculate significantly slower than the CalculateField geoprocessing tool with SDE datasets?

I just discovered today that there are essentially two ways to calculate field values in ArcObjects: 1. Using ESRI.ArcGIS.GeodatabaseUI.ICalculator: ITable table = …; ICursor updateCursor = ...
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Correct SQL expression when looping different fields

I'm having trouble with the follow lines of code. Practically what I am doing is a 10 shapefile loop in which field represents the name of the field that I want to be calculated( the name differs by ...
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Script (ArcPy) vs field calculator (Python Parser) behaviour of getPart in ArcGIS for Desktop?

From time to time I have to access geometry field and shuffle through points in it. Process is simple: Get shape Get it's part Iterate through part's points This is how it looks like in a script ...
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326 views

basic problem using division in field calculator

This is a very basic question, but I can't figure out what's going on. I've got election results I'd like to simply display as percentages rather than vote totals, which should be as simple as ...
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630 views

How to SUM field and then insert into NULL column?

I am only in the beginning stages of learning Python. I have a column, 'QUANTITY_SOLID', that I want to take the sum of all of its rows. I understand I can do this with 'SUMMARY_STATISTICS', but i'm ...
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195 views

Extract one GPS fix per day from data?

I am in the fortunate position of having 2 years worth of animal movement data. With such a large amount of data I would like to extract only one fix per day to make it easier to work with. Data = 14 ...
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How to Calculate Field in joined table using ArcPy?

I have to calculate a field based on another field in a joined table, but an error occurs: "Parameters are not valid. ERROR 000728: Field !Table_A.field_A! does not exist within table" My code: ...
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Field Calculator VB Script Codeblock IF statement syntax is wrong?

I can't figure out why the syntax is wrong in Field Calculator ArcMap 10. The complete codeblock is Dim CapitalDia As Number Dim TwagDia As Number Dim X As Number CapitalDia = [New_Pipe_S] TwagDia ...
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split string after first word

I want to split a string field after the first word using the space as a delimiter so that "WA ROSSOUW ORANJE BELEGGINGS" becomes "ROSSOUW ORANJE BELEGGINGS". I am using Arcmap10. Thanks.
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Is there a Log or Ln function in QGIS Field Calculator?

I can't seem to find any way to take the logarithm (natural or base 10) of a field in QGIS. I have gotten to the field calculator but there is not a button for log and I can't seem find any formula ...
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100 views

Using ArcGIS Field Calculator to populate new field from old field

I'm trying to assign speed values to street types using TIGER street shapefiles. So I created the new field for the speed, and I was going to use the field calculator to take the MTFCC classifications ...
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844 views

Calculate average value for each row

The picture is an example, but the method would be the same at mine bigger dataset. So i have some parcels with each a ID value and some fields. such as field 1, field 2, field 3, fieldd 4,... with ...
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Field calculation- Arcpy

I am developing a script to calculate the values of two fields (C and D) based on value of field A (It is a Point feature): A C D 0.2 1 1 0.2 1 2 0.2 1 3 0.4 2 1 0.5 3 1 0.5 3 2 So the idea is n ...
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Iterative position within Field Calculator/Python

I'm not great with Python or programming in general, so I'm not even sure how to ask this question. Basically what I've got is in the left column, and what I want is in the right column. UniqueID ...
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Nested “if” statements in ArcGIS Field Calculator

The solution in VB for the base process is @ "If then" VB Script code (or Python) equivalent to SQL's IN ('x','y',z') expression in ArcGIS Field Calculator question? ...
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1answer
2k views

How to summarize a column in QGIS field calculator

I have data with a column containing a number value, and I want to divide the value of each feature by the total sum of all the values in the column (to get a percentage). So I would like to know if ...
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819 views

Calculate Field in ModelBuilder gives General error executing calculator. ERROR 999999: Error executing function. Expected end of statement?

I am attempting to do zonal statistics for multiple images and I need to add an extra field that will have the name of each raster file in each row to the finally appended file. I have added a field ...
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Can Hyperlink be based on two fields for path and file name separately?

I need to create a hyperlink field. I have one field with the file name, and another field that contains only part of the file path (the real path is unknown). The table contains 14,000 records with ...
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How to concatenate numbers and add in leading zeros?

I have three text fields populated as follows: 1, 9, 1 that I need to concatenate into a field that looks like 01.09.01. Getting to 1.9.1 is easy but can anyone help out with how to formulate it so ...
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Why can't I multiply two string fields in the Field Calculator by converting them to int() and float()

I'm using ArcGIS 10 and new at python scripting. I have a string field that I need to calculate by multiplying two other string fields. I can do it in python using two arbitrary values... CINPT1 = ...
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VBA functions use in ArcGIS Field Calculator

Would this be ok to use them for the field calculator in ArcGIS 9.3 ? See here MS Excel VBA Functions Or should I fix them in MS Excel and save as a file and then use the join with the shapefile or ...
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Remove decimal points from string field using field calculator

I have a string field populated with shape lengths in my attribute table but they have 12 decimal points. How do you remove decimal points from a string field populated with numbers using the field ...
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Using UNC pathname with Calculate Field tool in ArcPy?

This question is different to Using Calculate Field to fix hyperlinks in ArcPy gives Cannot use VB for services? which was asked previously because it is using the Python parser specifically, rather ...
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1answer
383 views

Replacing multiples words using field calculator in attribute table python

I need to replace multiple words with one word in a field at one time in one script. Example in my LettersField I need to replace all the "Aa" and all the "Bb" and all the "Cc" with "Rr". I am ...
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1answer
372 views

How to use Field Calculator to assign values to only Odd (or Even) page fields for Data Driven Pages?

I am creating a map book but do not want the page numbers for each map page to be on the same side (since its printed double sided), I need the page numbers to be placed on opposite sides? I am using ...
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1answer
185 views

Are Date columns in feature classes stored as python datetime objects?

I have a Date column called readings_measurement_tstamp stored in my feature class. I would like to add a String column to this feature class and Field Calculate it to be be just the %H:%M:%S ...
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How to replicate trunc function on QGIS?

I've search a bit before asking this question, but I haven't found the answer. Is there a Trunc function on QGis? I've tried using floor, but it doesn't work (like I want) if the number is negative, ...
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How to use the Intersects function in the Field Calculator of QGIS?

I would like to have an example on how to use the Intersects function in the Field Calculator of QGIS. Basically, I want to know which feature from a polylines layer intersects a polygons layer and ...
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Using Calculate Field (Data Management) tool to calculate 3D Length in ArcGIS 10.1

I'm relatively new to the world of model builder and scripting, so it's likely there is a very simple solution to the question I've been trying to figure out. I'm trying to create a tool that takes ...
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1answer
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Unit of $length in QGis Field Calculator

I'm calculating field of various features in my shapefile using QGis. I'm getting some sample length as 0.134914579766986. I want to know in what unit (eg: meters, km etc) is the above value ?
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arcpy: check for same record in cell above and below

After using the find duplicates in arcmap 10, I want to check if the feat sequence ("find duplicates" marks all records with the same attributes with the same number [in "feat_seq"] and creates a ...
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How to concatenate two fields (type double) into a single field?

In arcgis 10.3 using the field calculator I'm trying to concatenate a census tract field (double) with a census block field (double) into a single field that has the two values separated by a decimal ...
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Qualifying field names in field calculator

I am trying to set up a quick model that: Takes a point feature layer of development projets (a table in an access database with xy coordinates), Spatially joins polygon neighborhood designations to ...
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1answer
78 views

Using Python strip and split functions in ArcGIS Field Calculator?

I am trying to populate a field with the last word in an address string using field calculator within ModelBuilder. My code takes the whole address string (1234 S Brittany Town Dr) as a parameter, ...
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How do I use Python to edit a field in an attribute table?

I have a few data tables full of information on salt water injection wells, with injection volumes given on a monthly basis. I need to add these monthly values up in order to get an annual value for ...
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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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110 views

Area calculation of an object without coordinates

I have a photo of an object with a scale and I want to calculate its area. I guess I have to create a polygon of the area to be calculated to use the 'field calculator'. But how do I tell the program ...
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1answer
429 views

Debugging Visual Basic Code Block in calculate field using ArcGIS Desktop?

From time to time, I have to use Visual Basic in Calculate Field. As the code get bigger, the more complicated is to debug it. And ArcGIS (9.3) does not help as the error messages are, in the best ...
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Why doesn't the Field Calculator work in ArcGis 10?

When I try to calculate a field nothing happens. I have always been able to just select the field, open the field calculator and type = and the new number. This is frustrating because the other GIS ...
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1answer
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Auto-generated field in ArcSDE for end user

The objective: Create a process where a coworker can open an .MXD, start editing, add a feature to represent a complaint, then add records in a related table to represent an inspection. Along the way, ...
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Field Calculator does not notice selection? [closed]

I have a problem with the Field Calculator in ArcGIS 10. I selected specific points of a Shapefile I want to calculate, but FC is always calculating all fields. Unfortunately there is no checkbox in ...
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How I can reverse numbers in a string without reversing any text? [closed]

I have a string, I need to reverse just the numbers in the string without the text: String: [321 test] The result will be: [123 test]
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Setting Zero values back to NULL

I'm working with ArcGIS 10.2 for Desktop and OS Windows 7. I need to set numeric vales from Zero back to NULL, but I can't from the field calculator. I'm working with a vector file and I need to ...
3
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127 views

Arcmap field calculator python script returns no data

I am running ArcMap 10.2 I have 4 fields with which I am working. many have duplicate entries. in order to find the single correct entry from all the duplicates I am trying to calculate out the ...
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Round decimal number in ArcGIS10.1

How can I round the decimal number in a table in Arcmap: e.g. how can I set it to 2.60?