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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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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1answer
94 views

Using Python parser of ArcGIS Field Calculator to populate values in one field based on those in another?

I am trying to populate a field with a sorting code that represents the value of another field. Example: EXPCODE|SORT| S4DNN2 |3.5 H2BNN2 5.0 EXPCODE is a field with a value like "S4DNN2." SORT ...
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270 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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1answer
73 views

Using defined function code block with Python in ArcGIS

I am running a Field Calculation within a Python script in ArcGIS. Within this Field Calculation I am calling a defined function within a code block. Here is the dialogue that I ran and works: ...
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2answers
150 views

How to add multiple python expressions in field calculator

How would I add multiple python expressions in the ArcMap Field Calculator if possible? I tried separating each expression on a new line and also separating with a semi-colon but neither worked. ...
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2answers
66 views

How to add “0” to multiple parts of text value in Field Calculator with Python

I have values in a text column that are as follows: 000_100 100_200 ... 1000_1100 1100_1200 I want it to read: 0000_0100 0100_0200 ... 1000_1100 1100_1200 I want all values to have the ...
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1answer
149 views

if-else logic expression in field calculator

I want to calculate the value of a new field using an if-else condition with field calculator in modelbuilder. Want I want to do is as follows: if my new field is empty, then use the expression ...
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2answers
50 views

in attribute table [closed]

Rows consist of letters and numbers that had 6 strings expression. I want to group these rows according to at least 3 strings be similar. How can I do?
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0answers
57 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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2answers
347 views

Calculate field

I am working in ArcMap 10.2 and would like to calculate a field. The output should be the value of 'field 1' only if 'field 1' has a value 0 or it should give the value of 'field 2'. How to do ...
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4answers
400 views

How to remove period, comma, symbols using field calculator?

I want to delete . , # in attribute table using field calculator (VB Script or Python). How can I remove these using this example address: N. First St., Unit #1 (I don't need city or state name) I ...
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1answer
351 views

Iterate through all fields in attribute table and multiply by field

I have a table with a whole bunch of census variables (race, age, education, etc). I want to multiply all of these fields by a factor that I calculated. For example: Field1 has values of 10,20,30,40 ...
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105 views

How to change GK-coordinates to UTM with the field calculator in QGIS?

i have a qgis project in ETRS89 (UTM) with some vectorshapes. i already transformes them from GK into UTM. but now the attribute table still show me the GK-coordinates. HOW can i change it? with the ...
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1answer
83 views

Problem with addιtion abstraction in Field Calculator

I want a bit analytical respond for the mistakes I have done in my code cause I am new to programming. I am using ArcGis 10.2. and I must process a field with distances in an attribute table I have. ...
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1answer
463 views

Converting 12-hour time to 24-hour time using Field Calculator

Does anyone know how to convert string time formats in ArcMap v10.2 from 12-hour to 24-hour using a simple query in the Field Calculator? i.e. NO Python, NO editing in Excel, NO changing my Windows PC ...
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1answer
131 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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3answers
589 views

How do I normalize the values in a single Field (from a table) in ArcGIS?

First of all, this is my first post, and I would like to appreciate all the useful information I have found so far on this site. Second of all, I have encountered a problem, in Field Calculator. ...
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1answer
63 views

Concatenating fields while also replacing values within certain stings [closed]

I am trying to use python to concatenate multiple fields in a polygon layer. Specifically, I am attempting to combine the values of four fields into one: EXPCODE = !MATRIX! & !PLANT! & !PCT! ...
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2answers
488 views

How to convert negative field values to positive?

I have an xyz file that I want to convert negative field values in the z column to positive values. How do I do this with field calculator?
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3answers
142 views

How do I use the field-calculator in QGIS to return the name of a country from a different shapefile?

I have a shapefile that consists of a list of archaeological sites with the x and y coordinates. I have an Natural Earth shapefile for the countries of world. I was wondering how I go about ...
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1answer
38 views

ArcGIS do calcuation on multiple input fields of attribute table and the number of input fields is changing

I have attribute table with headers: ID(bgrp), F1 (F2011_46), F2 (F2011_48), ...Fn I want to do math calculations on the fields from F1 to Fn. For example, count the total number of non-zero Fn ...
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24 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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1answer
32 views

Polygon shapefile field calculator problem

My project is set in WGS84 only, and I have checked 'enable on the fly'. I have created a polygon shapefile and my problem is that when i use field calculator in the attribute table on my polygon ...
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1answer
47 views

Raster Calculator or Local-Combine tool? (in ArcPy)

i have 3 classified rasters and i wanted to use the following query from r. calculator: (rclslope>=45) & (rclmosaic>=2000) & (rclfocal>15) to arc.py how can i write it? Is it ...
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4answers
1k views

Concatenate string data plus numeric data in Arcmap 10.2.2

I have three attribute fields (Address_No: 1, StreetName: Main, Street_Ty: ST) that I want to merge together. How do I concatenate string data found within the table plus numeric data? I would like ...
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49 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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1answer
237 views

How can I allocate a $rownum in reverse order in QGIS?

How can I allocate the $rownum value in reverse order in QGIS? I have a created a grid layer to use in an atlas and the ID allocated is from top left to bottom right - which is what I want if I want ...
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2answers
347 views

Calculate field management not working within customized Python tool in ArcGIS

I am trying to make a custom made Python Script tool which I would like to use in Model builder. I am using the arcpy.Calulate_field_management function (simple reclass function as an example), but it ...
3
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2answers
318 views

VB Script or Python for Field Calculator when using greater/less than?

What I have: I have 4 fields for my address ranges. L_ADD_FROM, R_ADD_FROM, L_ADD_TO & R_ADD_TO (all in DOUBLE field type). What I need: The lesser value from L_ADD_FROM and R_ADD_FROM to ...
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2answers
411 views

ArcGIS field calculator: Calculating a new field using multiple fields with python

Basically, I have a large polygon data set that has soil data for an area and I want to assign numeric values to the data based on soil texture text values (e.g. SIL=4, CLY=7, ...). However, the soil ...
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3answers
2k views

How to calculate a value based on another field under arcpy.da.UpdateCursor and cursor.updateRow?

I am trying to do a calculations under arcpy.da.UpdateCursor. I want to calculate the values for the records that have FIPS=06037. I want to take the values from "kg" column and populate the new value ...
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1answer
218 views

Calculate field based on other two added fields in ArcGIS Model Builder

I have a model in model builder where I add 2 fields, "field 1" and "field 2". For each field I calculate their values using the calculate field tools. Afterwards I add a third called "Field 3" of ...
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2answers
82 views

Use Python in Field Calculator to increment up value

Please see screenshot for field calculator Python logic. I have no idea what I'm doing that's any different from this GISSE answer. The error I receive is ERROR 000989: Python Syntax Error (invalid ...
2
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2answers
584 views

Cannot convert string to int using ArcPy Calculate Field

When I load a csv file to join with ArcPy, it converts all string fields that are numeric to integers. Therefore, I have to add another field within the feature class that I'm using for joining that ...
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1answer
220 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 ...
2
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1answer
31 views

Create field on open ArcGIS map - not saved

I am using ArcGIS desktop with an SDE feature layer with enterprise data that I do not have rights to edit. The data changes weekly but I need a field that is sum of 2 current fields without creating ...
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1answer
169 views

if/then with VBScript in ArcGIS Field Calculator giving Error 000539: SyntaxError: invalid syntax?

What is wrong with this VBscript in the field calculator? ColumnC= if [ColumnB] > 0 then [ColumnC] = [ColumnA] / [ColumnB] endif Each time I receive this syntax error message: Error ...
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1answer
254 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 ...
2
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1answer
48 views

Unexpected behaviour when summarizing a field in ArcMap (Un-Equal strings)

I couldn't figure out why when I use summarize the Field " LandUse_Arabic " it the summary shows two identical values in the output table. But when I use select by attribute, despite the fact ...
2
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1answer
376 views

ArcGIS Python syntax error using nested if else

I am trying to use the field calculator in ArcMap 10.2 to fill an empty field based on the contents of two exiting fields usint this python script in the Pre-Logic Script Code. def ...
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0answers
77 views

Line length for line files

Using QGIS, Brighton 2.6. Trying to calculate line-lengths for linear features (roads, trails, fenceline) and used this post (How to find line length in QGIS while editing?) and the links associated ...
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2answers
270 views

Using Python in the field calculator - if/else over multiple fields

I'm trying to work out how to populate a field depending on the lowest score across 6 other fields. I've read several other questions relating to if/else statements but I'm only just starting to learn ...
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2answers
162 views

Setting field equal to raster Name ID for batch process in ArcPy

I am wanting to set an existing field called RasterID to the name of the raster for which the attribute table belongs to, but for a batch of rasters. Is there a way to do this with my current code ...
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2answers
87 views

Using ArcGIS field calculator? [closed]

This field calculate returns an error, whats wrong with it? def Reclass(A): elif ( A>= 0.208113 and A <= 0.261517): return "Low" elif (A > 0.261517 and A < 0.301951): return ...
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1answer
853 views

Populating a field in an attribute table with a consecutive number sequence? [duplicate]

I know that this is probably a very basic question but I cant seem to find an answer through Google searches. I would like to create a field in an attribute table (in ArcMap 10.2) for a Number Label ...
3
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2answers
271 views

How to pad field with blank spaces using calculate field tool of ArcMap?

I am trying to pad the right side of a field with blank spaces so that when I label the field, it labels further over to the left. The only way that I can seem to make this work so far is by adding a ...
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1answer
313 views

Calculate values in one field based on values in another field

I have one field with Zoning Codes (i.e.: RS) and I want to update another field with the string "Residential Single Family". The new field is currently NULL, I would like to add the full text string ...
3
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1answer
661 views

Joined tables and now field calulator is greyed out

In ArcMap (10.2), I accidentally calculated the wrong field outside of an edit session, so there was no way to reverse my action. I restored a previous version (shadow copy) and joined the tables ...
7
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2answers
568 views

How to find if polygon has a hole using field calculator in ArcGIS

Some 3rd party software cannot handle polygons with holes (donut polygons). To find them I always use ArcView 3 field calculator, because: however when I try to do this in ArcGIS, I get this: So ...
0
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1answer
55 views

Sum a field, and take that sum and use it to populate an existing field in the same table

I am trying to break down land uses in a watershed by making a tool in ModelBuilder. Right now I am clipping a land use layer by a watershed polygon, dissolving land use layer by land use code, ...