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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Calculate area intersected areas, problem

(I'm working in QuantamGIS) I intersected two layers creating a new layer. Within the attibute table of this new intersect layer i would like to calculate the new areas. However, it just doesn't ...
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1answer
53 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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29 views

Combining and extracting attributes from 2 columns to populate a third (Concatenate)

I am working with a FEMA flood zone shapefile which contains a FIELD_ZONE field and a SUBTY field. I created a third field called ZONE_TYPE that needs to be populated by combining or extracting ...
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4answers
150 views

Python script for Field Calculator. ArcGis 10.2.2

I have a point shapefile with two columns i want to process. The first column is aspect and the second is aspect_m60, there is only one row with the aspect of my point. I have tried to write a script ...
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1answer
37 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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1answer
26 views

How can I make attribute table field dependent? [duplicate]

In an attribute table I am making new fields bounded each other by the Field Calculator. Once I have written the formula for the new field in the Field Calculator, ArcGIS make the calculation for the ...
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2answers
77 views

Using ArcGIS field calculator? [on hold]

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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4answers
1k views

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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1answer
39 views

If statement problem in Field Calculator - Arcgis

I have a field entitled "Lung_lunc". It contains some "0" values and the rest are values > 0. I want to turn those "0" values, into "0.0001". I have added a new field: "Lung_lunca", and I want to use ...
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2answers
86 views

How do I add rows together to populate a new field?

How do I add the values in columns 11_acciden, 12_acciden, 13_acciden, and 14_acciden in order to populate the total_acci column?
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1answer
47 views

How to fill the column in attribute table with same values?

I have about 19000 records, I added new column and I would like to fill it with string values (eg. brand)- same value for all rows. I'm not considering copy/paste. I know I could do it with exporting ...
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2answers
54 views

How to assign a unique ID to groups of items in the attribute table in ArcMap?

Using arcmap's field calculator I need to programatically loop through all of the entries in the field and for each name it gets its own unique id. So names that are the same would get the same ...
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1answer
40 views

How can QGIS Field Calculator sum values from a spatially joined table?

Can the Field Calculater be used to sum values from a related table via a Spatial Join? I have two vector polygon layers A and B, each with a numerical column VALUES. I want to update VALUES in ...
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2answers
157 views

Performing math in Python parser of ArcGIS field calculator?

I never used python but now I need a code to do this calculation: I'm doing this: math.atan(math.fabs( !Y2! - !Y1!)/math.fabs( !X2! - !X1!) )*(180/math.pi)
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1answer
34 views

ArcGIS Field Calculator nested elif is None not working

I am calculating a field based on two other fields in ArcMap 10.2 using python. My Pre-Logic Script Code is def myfunc(legend,Btype): if(legend == 'Apple'): return 'Banana' elif(legend == ...
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3answers
13k views

Basic If/Then in ArcGIS 10.2 Field Calculator (Python or VB)

I've been looking through these threads and can't seem to figure out my answer yet. Very new to VBA and Python, but lots of years with Arc.I know I can do this the slow way with Select By Attributes, ...
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1answer
71 views

Rewriting VB codeblock as Python for ArcGIS Field Calculator?

I am looking for assistance to rewrite my VB codeblock into Python. Im on Win7, Arc10.2 and Python 2.7 The code below works fine for me, I am simply looking to port it to Python so i can progress down ...
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1answer
27 views

Combine string and OBJECT ID

I would like to update the Map_Feature_ID field with a String " WP_" and then follow the "WP_" with the OBJECTID field. So I will end up with "WP_1", "WP_2" all the way to the end in the Map Feature ...
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3answers
534 views

Replacing Variable in VB-Expression-File (.cal) of ArcGIS Desktop?

I'm trying to modify a VB-Expression saved in a cal-file by ArcGIS Desktop 9.3: dim out if [D19830701]=-9999 then out= [D19830501] else out= [D19830701] end if ...
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1answer
80 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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1answer
71 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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1answer
210 views

How to create sequential field based on sorted data? (or extract pop-up data?)

I downloaded a kmz field and converted it to a GDB fc on arcmap. However, the field I need to label the layer by is stored in the pop-up html field... It looks like this: <html ...
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1answer
70 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
430 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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2answers
429 views

Can anyone tell me why my field calculator is returning this error?

All I am trying to do is pull into a text field, a section of another text field via: fieldB = !fieldA![some_index:other_index] However I keep receiving the error below and I can't figure out why. ...
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46 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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1answer
34 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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1answer
38 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
42 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: ...
2
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2answers
83 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
50 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
170 views

Calculating a Unique ID on a Subgroup of Polygons

I would like to assign a unique ID to polygons in a dataset. The catch to my issue is that I would like polygons that fall within a polygon to have the same unique ID. My example is related to ...
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2answers
47 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
29 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 ...
1
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4answers
76 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 ...
3
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1answer
147 views

How to calculate the intersected area from a layer with overlapping buffers in qgis

I need to calculate the area of landusetypes in 50m around various dots (all in one shapfile). My problem is, the buffers around the dots are overlapping each over in some places. I tried to ...
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3answers
2k views

ArcGis Python Script, Calculate Field

Sorry for my English. I am trying to write a Python Script for ArcGis 10.2. #import system modules import arcpy import math from arcpy import env #Set environment options ...
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2answers
280 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 ...
0
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1answer
75 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. ...
4
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2answers
3k views

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 ...
0
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1answer
42 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 ...
6
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1answer
112 views

How to remove comma from combined fields which should be null?

I have Drivers License as one field and State as the other and there are to be combined and formatted as Drivers License, State. How do I handle records that do not have either a Drivers License or ...
2
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1answer
32 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 ...
4
votes
1answer
206 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 ...
2
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3answers
110 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
53 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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2answers
463 views

area values determined with field calculator become null when saving

using field calculator in Qgis 1.8.0 to get the area, it shows just right at first but when I save it, the values become Null. help please
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1answer
40 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! ...
1
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1answer
335 views

Join and Calculate vb.net

Im trying to join an excel table to a shapefile and then calculating those fields using vb.net. The code I have written has no errors, but won't work when I try it in ArcGIS 10.1 and I'm out of ideas. ...
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1answer
218 views

Slow performance with Add Join and Calculate Field?

I have a point layer and a table with approximately 100 fields. I need to join the table to the point layer based on a key field and create a new shapefile / feature class. This script has been ...