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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If/then VBScript/Python code equivalent to SQL IN ('x','y',z') expression in ArcGIS Field Calculator?

we need just like the following, only with multiple records selected... have tried the "xyz" in (1,2,3,4,5) SQL code but of course VB Script wants something else. dim f2 if [field1] = "foo" then f2 ...
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Using IF operator with Python parser of ArcGIS Field Calculator?

I want to assign numbers to a certain types of building and I need to use field calculator. I tried many different versions of this and I still cant find whats wrong. Could you tell me where do I ...
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570 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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617 views

Cannot compute area of shapefile in field calculator of QGIS?

This shapefile represents the counties of NM. I am trying to compute the area of each polygon (yes, I know there is an area field, but this is a simpler example of a problem I'm having which doesn't ...
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How to insert a quotation mark through the Field Calculator of attribute table of a Shapefile?

I have a shapefile of polylines with information of diameter. But the problem is that i didn't enter the inch sign(") with the values of diameter. What would be the solution that qutation mark would ...
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Elseif Conditional Statement in QGIS Field Calculator

I am trying to write an ELSEIF conditional statement in QGIS Field Calculator (version 1.8.0). I have used an example I found online: CASE WHEN val < 0 THEN 'negative' WHEN val = 0 THEN "neutral'...
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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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603 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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661 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 = table....
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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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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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647 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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196 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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103 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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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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How to use the field calculator's centroid() Geometry function in qgis 2.0?

There is an option in the field calculator for centroids under geometry which when you double click gives you "centroid( ". What information is required here in order to use this function?
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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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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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871 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
416 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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386 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
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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 ...
4
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2answers
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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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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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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
433 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 ...