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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How to use Fields in the Field Calculator? [duplicate]

I'm using the Field Calculator in ArcMap and I need to create a unique ID for every storm drain in my county. An ID Should look something like this: 16-I-003 The first number is the municipal number ...
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137 views

Using the Rule-based style to calculate each grid cell from overlaps

I am using the Rule-based styling properties (QGIS 2.2) to determine the colour of grid cells for a merged shapefile. Each grid cell defined by its ID may be overlapped by several layers as defined by ...
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72 views

Arcgis 10 assign values to field based on values in other field [duplicate]

I have a table with two fields A and B, and i want fill field B with "some values" from field A: FieldA: 123456_CC; 123_D; 1234567_AB; 123456768_F I just need the "text" that is associated with the ...
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77 views

Create and immediately update field using Field Calculator

You can create fields and once created, populate them with data using the Field Calculator. But can you do both at the same time using an expression? Or must you do it in 2 steps?
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30 views

Does ArcGIS Desktop have conditional function useable in field calculations?

Does ArcGIS / ArcView 10 have a conditional function, e.g. ifx(test,if_T,if_F), that could be in-lined in field calculations?
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172 views

Calculate field based on most frequently occuring text/value in other fields in attribute table (ArcGIS)

I was wondering if anyone knows if it is possible to calculate a field based on the most frequently occurring value in other fields. What I have is 5 fields with crop information over 5 consecutive ...
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536 views

How to add a new column in attribute table with attribute with indexes of another max-min ordered attribute field?

I've an attribute column named e.g. VALUE with different values I would like to make a column named e.g. ORDERsuch that the greatest value has the attribute 1 the second value 2 etc. etc. so order ...
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304 views

Cursor Update Python Script for Multiplying Several Fields against a Ratio (Real) in ArcGis

Disclaimer: Python Neophyte, Uber-reliant on GUI, working to wean... I have a Python script for replacing multiple Field values with another table value that was graciously provided by the inimitable ...
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257 views

Using a different projection to calculate areas using the Field Calculator

I have a dataset that is in a WGS84_UTM projected coordinate system, can I force the Field Calculator to use another coordinate system when I use it to calculate areas using pythons ...
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361 views

Convert a number in attribute table to binary

I would like to convert whole integers from decimal to binary in ArcGIS using the field calculator. I am looking for the equivalent of DEC2BIN excel command. All values are 255 or below so 8 bit is ...
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335 views

Stop rounding values in Qgis attribute table

I am calculating the areas of my polygons in Qgis using $area and everything works fine until I click on "save". All my values are rounded to an integer. I tired setting the output field type to ...
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74 views

How to move a value from field1 to field2 using Field Calculator?

Hi I would like to move value in field1 to field2. Purpose is to after that delete the column 'field1' to get a better column naming standard /Jan
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657 views

How do you calculate a column value based on the value of another column?

I am trying to select data based on whether it starts with certain characters and then update a field. For example if [Asbuilt] starts with "WL" then do something. Here are the two methods I have ...
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3k views

Use Round in ArcMap 10.x Field Calculator on field with both numeric and NULL values

With older versions of ArcMap (9.3, 9.2, etc) I was always able to round numbers down to 2 decimal places using field calculator even if that field had both numeric values and a bunch of NULL values. ...
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1k views

ArcGIS field calculator: VBScript get data from previous row

When using the field calculator, how do I get data from the previous row in VBScript? In Python I'd do something like this: for index, row in enumerate(rows,start=1): row[index-1] += 5 I'm ...
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41 views

Update all cells in column to match value of first row?

I have a point layer; the attribute table includes x and y coordinates of original centroids associated with the points (the points were generated from the perimeters of circle features and still ...
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41 views

Error msg “Name is not defined” when trying to populate a field with the shape file name

I am trying to populate a field with corresponding file name. For example, if the file name is Route1.shp then the field value will be Route1 as well. However my code is not working. Can you please ...
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Using “calculate field” in python script fails to display Arabic characters correctly

Using “calculate field” in python script fails to display Arabic characters correctly. I have exported the modelbuilder to python script, but unfortunately the Arabic characters cannot by displayed ...
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49 views

Getting and using XY centroids in ArcGIS Field Calculator using Python Code Block

I am writing a script to obtain Grid reference but cannot fathom how to get XY centroids without creating new fields (all examples I have found are based on writing XY centroids to field). Here's ...
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64 views

Attribute table not updating after QGIS field calculator used? [closed]

Using QGIS 2.8.1 i am trying to update an attribute table using the field calculator. its a vector layer of vegetation communities. i am trying to update the area fields in the table. The output ...
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63 views

new layer from calculations with fields of other layers in QGIS

I've two layers, both with the same fields: A, V, where A is the shape's area and V a value given by me. I want a new layer with shape created by the intersection of the other layers' shapes and a ...
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26 views

How to update the value of a field dependant upon the the fields ID in QGIS Field Calculator

I am looking to create links to website pages and to automate the procedure a bit more I would like to have a standard link followed by the ID of each field. For example, I would like the standard ...
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76 views

Use field calculator to reclassify values from three different fields to populate a new field AND determine overlap with different raster

I want to reclassify values of 3 different fields AND determine if one of those fields is located inside a different polygon to populate the values of my new field. Everything is raster. I created a ...
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162 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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75 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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270 views

How to Calculate Cumulative Field Values in Arcmap

My problem is conceptually quite simple; In Arcmap 10.2, I wish to create a field which contains the cumulative values of another field in the same attribute table. For example, if the first three ...
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279 views

How to calculate unique IDs starting from highest current ID

I have been using a python script in field calculator in ArcGIS 10.2 to add unique IDs automatically, however there are two things I would like to improve this process: Each ID also has letters at ...
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107 views

If/then Field Calculator

I have two fields in my model, the first is a spatial join return for the township, the second is a spatical join to a city. If there is not city, then the field is left blank. The column that has ...
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71 views

Use Field Calculator to change “Status” field in Annotations

I am trying to turn off a lot of annotations at once by using Field Calculator to set status to Unplaced. Just typing "Unplaced" into the expression, I get this error: The calculated value is ...
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210 views

ArcMap 10.1 Crashing when using field calculator

I keep getting a serious error message when I try to use the field calculator. I've joined a .csv to my SDE feature class and am trying to set one of the columns equal to one of the columns from the ...
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140 views

Updating a feature class

I am working on ArcGIS 10.2.1. I have a feature class containing more than 4000 records and a table having approximately 1000 records. Both feature class and table have some common fields however, ...
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175 views

Conditional Calculate Field Many to One

Anyone have experience calculating a field based on a many to one scenario? I have a feature class in a geodatabase with a field of unique names. Feature Class Table (let's call this ...
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345 views

Autoincrementing Python Script is over writing all fields versus just fields that are null

Using ArcMap and the Field Calculator I have a python script that should autoincrement the FacilityID field if it is null. It works the first time through but the second run causes it to overwrite ...
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239 views

Replacing attribute table entries using Python script

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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1k views

Getting ValueError: max() arg is an empty sequence on a Python Script in the Field Calculator in ArcMap

I have a script that populates a FacilityID Field on a Attribute table in the Field Calculator but when I run the script below I am getting a error. EDIT: Python Script: def autoInc(): import ...
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Field Calculator extract three last digits from another field

How everyone! I have two fields the on is the cadastral number which is for example 051020213001 and I am trying to fill the other field (label) with the last 3 digits from the cadastral number, in ...
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245 views

Auto increment a new column using Model Builder Field Calculator in QGIS?

I am making a model which requires creating a grid and clipping various layers to it. Using the Create grid function does not provide an ID column, instead it creates 2 columns: "longitude" and ...
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174 views

Error when dividing a field with a number

Using arcpy CalculateField_management i want to divide a field with a spacific number: arcpy.CalculateField_management(EZG_shp, "IDX_AT_PK", "(!EURO_SUM!/!Anz_Pers!)/1668,4","PYTHON") This works in ...
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50 views

How can I populate a field of the polylines to indicate if they intersect?

I have two feature classes, one ploylines, one a buffer. How can I populate a field of the polylines to indicate if they intersect?
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436 views

Calculating Stream Length-gradient Index (Hack Index) with the field calculator

I'm trying to calculate the Stream Length-Gradient Index of a stream (example data below). Just started to get into python, but am struggling with a solution to this problem. I have 42 streams to run ...
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139 views

Problem in long expression in field calculator

I am trying to compute the following expression with Field calculator. The input table values are around the size of this value: 562643580,7843, and the field name (the field of destination) is: ...
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225 views

Is there a way to automatically calculate attribute values for new features?

I am creating a vector point layer which will be added to over time. I have been using the field calculator to populate fields such as X and Y coordinates. I'm wondering if there is a way to have ...
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208 views

Help with field calculator in Python script

I am getting a syntax error in my script but I know from testing it in ArcMap attribute table, the syntax is fine. Anyone have any idea why this code doesn't work? I see that a search cursor has been ...
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341 views

VBA ArcGIS 9.3 Field Calculator: 'countif' across several fields

I have an attribute table with 15 columns that contain either a '0' or a taxonomy number. I would like a summarized column that shows the number of different species. location type1 type2 type3 ...
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111 views

How to perform intersect operations in the Field Calculator in QGIS?

How to use the Intersect function? How would I specify to REPLACE layer1.field1 with layer2.field2 WHEN layer1.geometry INTERSECTS layer2.geometry Is that feasible in QGIS?
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219 views

How to correctly use LIKE in the code block of a Reclass expression in ModelBuilder Calculate Field

I have a Reclass expression that works when i am search for single instance of a data field. I also wish the Reclass to work with a SQL type LIKE selection with Wildcards. e.g. I need to reclassify ...
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323 views

Python Field Calc for Document Hyperlink

I am trying to create a script that will hyperlink to a .tiff or .pdf. These files are stored in one folder on a shared server. I want the script to look in a field: 'PLAT_IMAGE', which has the plat ...
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407 views

remove whitespace Python code results in odd character - Field Calculator

I need to remove whitespace from the end of a string in a field in ArcMap. I tried first the VBA function RTrim, but whitespace still remained. I thought maybe the whitespaces were tabs, so I tried ...
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209 views

Comparing field values to update new field using ArcGIS for Desktop?

I am currently doing an analysis in ArcMap 10 using python. I have two shape layers, one is a point layer and the other one is a line layer. The point layer have attributes for point's unique ID, as ...
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110 views

How to reach a field value of a record in field calculator in ArcGIS 10.1

I have two fields showing number of people in two age groups "young" and "old". these people also live in a cell (point) whose distance to a specific facility is calculated. then I categorized these ...