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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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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156 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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182 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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360 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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262 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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2k 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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59 views

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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269 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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190 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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51 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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464 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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142 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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229 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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215 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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113 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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239 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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347 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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433 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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218 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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112 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 ...
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559 views

How to calculate field as cursor name?

First time dealing with cursor. I have lines intersecting polygons, I want to get a table with all attributes of the lines, add a field and calculate the field as the name of the polygon. I was able ...
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95 views

How to import text only out of a string field to a new field

I want to import data out of a string field in my shapefile to a new field for labeling. The string field contains river names and codes and I just want to display the text i.e river names
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433 views

Field Calculator Runs In IDLE (2.6.5) but not ArcGIS 10 SP3

just wondering if anyone else is having issues with the field calculator in ArcGIS 10 SP3. In the following code I do a pretty simple field calculation with a variable (an array) as one of the ...
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Do QGIS Field Calculator xat(n) and yat(n) functions work in version 1.7.x?

I'm trying to use the xat(n) and yat(n) in the Field Calculator but can't get them to work. Does anybody have an example how to use them? I need the start and end coordinates for line segments, does ...
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35 views

How do I Calculate Grouped Percentiles or Batch percentiles in ArcMap?

My question is similar to this one which was answered successfully: Calculating Percentiles in ArcMap? My addition is how do I batch this solution for multiple files or apply a group-by feature to ...
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If then statement in model builder

I have a model that adds several fields, two which are manual inputs (County Name and User). I am manipulating several parcel layers (approx 90 counties). In my model, one field takes the state and ...
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25 views

Forcing area calculation into miles in QGIS (without changing the PCS) [duplicate]

I'm working on an assignment that requires me to create an area column in miles without changing the projected coordinate system. ArcGIS has a tool that can do this ('Calculate Geometry')-- does QGIS ...
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34 views

Using Advanced Python Calculator in QGIS Modeler

I'm trying to create a column with integer values based on a small function that basically uses conditional statements. In short, a reclassification. My attempt below: def getValue(Etat): if Etat ...
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63 views

How to use QGIS field calculator between different points of same layer?

I'm in a course learning about GIS systems, and we have recently recorded a gps track. I've exported this track as .gpx and imported the points into QGIS. Each point has a timestamp. One of the ...
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47 views

Coordinates for specific points calculated in QGIS Field Calculator?

I have got a layer in QGIS that is comprised of connected points which define regions of a country, thus the attribute table consists of 38 regions while the number of nodes in this layer is about ...
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33 views

Network Anlayst hierarchy evaluator [closed]

Working with ArcGIS (v10.2.2) Network Analyst and reformating the road network with a hierarchy evaluator and receive the following error message: The field evaluator result statement has multiple ...
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18 views

Incorrect Acreage QGIS 2.6.0

I have six polygons, all of (fairly) similar size. The first one is 8 acres, the others are obviously wrong with 120,000 acres, and 106,000 acres and so on. I am calculating with the field calculator, ...
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41 views

Systematic inaccuracy in QGIS shape area

I’m trying to find out why I get different area figure in QGIS than in AutoCAD when I’m using the same shape file? What I did is I drew a shape in AutoCAD, imported it in QGIS and used the field ...
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111 views

ArcGIS Calculate Fields gives Warning 000405 No records within table?

Situation: I have feature layer sitting outside processing extent in Environment settings. If I open layer's table and use field calculator - Calculate Geometry on some numeric field: it works ...
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59 views

How to fill column with several conditions using QGIS field calculator?

I know the synthax in order to fill one field with only one condition (field calculator): case When "attribut" = 'value' then value End But how to do populate automatically one field with ...
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55 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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26 views

QGIS (2.0.1): Field calculator for length not working - values way too high

Same problem as another thread: Field Calculator returning incorrect length and area values Trying to calculate length of a line shapefile, and field calculator is returning values that are way too ...
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120 views

Field Calculator stopped working

The field calculator seems to have stopped working for one of my attribute tables (it works fine on others). No matter what I get it to express (I've tried simply 2*2, just as a test) it just produces ...
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48 views

Trying to export stacked text to CAD using ArcGIS 10.2

I've been experiencing some unwanted results when trying to export stacked text to CAD using ArcGIS 10.2 for desktop. With the Export to CAD tool I can easily export polygons. However, I'm also trying ...
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61 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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162 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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47 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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35 views

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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82 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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83 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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258 views

Cumulative field calculation using Python in ArcGIS for Desktop?

I am using the following Python code to sum cumulatively but I need the summation to take place while the other field is equal to 1 and then again start the summation when it's equal to 2. I need the ...
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313 views

Cause of Field Calculator UnicodeEncodeError: 'ascii' codec can't encode character u'\xf6' in position 5: ordinal not in range(128)? [closed]

def Befahrung(value1,value2): if value1 is ' ': return ' ' else: return "G:\\Example\\" + str(value1) + "\\File_" + str(value2) + ".pdf" I try to create a field with a hyperlink. It works ...
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75 views

Calculating average of 3 fields where nulls are present

I have created a new field to calculate the average of 3 other fields in a table where nulls are present. Using python as the parser(with no code block) I used this: (!Slope_PCT! or 0 + !Flood_PCT! ...
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28 views

Can a joined-layer have its attribute changed depending on what layers are selected/deselected?

Using QGIS, I have a polygon-grid layer which covers everything, Layer_All joined with 2 other grid layers: Layer_1 and Layer_2, both of which intersect at various points. I would like Layer_All to ...
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551 views

Null value error with Python in field calculator

I'm trying to calculate the angle between two line segments in ArcMap 10.0. I have a point shapefile, so I'm using the xy coordinates of 3 successive points to calculate the angle. I'm trying to use ...