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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Field Calculator: Add “0” to the front of all values in a column

I have a table for each state with Zip Code values. The 5-digit Zip Codes that start with "0" have been reduced to 4-digits. I cannot figure out how to add a "0" to the front of all the values in the ...
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144 views

Lists in field calculator in ArcMap?

Would anyone please indicate to me why this is not working. I am trying to convert all instances of '02ND' to '2ND' for example where some of the input fields (f1) are already converted and some are ...
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2answers
107 views

Field Calc to change one digit in a sequence Arcmap

I have an 11 digit ID in one field I'll call "Current_ID". I would like to create a new field named "New_Field" and populate it with same value except I need to change the value of the 4th digit from ...
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4answers
4k views

Calculating acreage using ArcGIS Field Calculator?

What is the expression to calculate an acreage in USA ? I am aware that there is a geometry calculate but when you convert raster to polygon it doesn't do it's job and I have to use the field ...
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4answers
875 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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125 views

How can I do more flexible matching in conditional expressions than provided by LIKE?

With LIKE '%' works but I have had no luck with character ranges, i.e. [0-9] to match a digit. Oh for a regular expression ;)
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1answer
4k views

Delete first two letters from a string field

I'm looking for a field calculator python statement to delete only the first two letters of string entries. For Ex: !Name!.strip([0:2]) I know this syntax is incorrect. Thanks a lot
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500 views

Syntax error from Python parser of ArcGIS field calculator if then?

Using ArcMap - I would like to calculate one field based on the value of another field. I want to Update the field 'Date_Class' based on the value in another field 'MIN_YEAR_B'. I was trying to do ...
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3k views

How to Convert a Number to Percentage in Field Calculator

Using ArcGIS 10.2 and Personal geodatabase,I have a field with values of Numbers like 0.461538 and Type of "Double" can you please let me know how I can Export them to new Field in Percentage Format ...
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1answer
4k views

How to search text string and select item in QGIS?

I have a table attribute with complete roads name. I have to search items by digiting a part of the road name and I need to colour all the items selected. eg: ROAD NAME: / road 01 / road 02 / road 11 ...
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1k views

field calculator syntax error

I'm trying to calculate the direction the 'generate near table' function gives me into actual directions, N, NW etc. Azimuth would be a start too. I tried this script in the field calculator but it ...
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724 views

If/else statement in arcgis

I try to fill the fields with the condition if / else but it does not work. I do not know where is my mistake in the code. def TextValue ( !Classe! ): if !Classe! == "Steppe arbustive" or !Classe! ...
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67 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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2answers
697 views

Calculate Fields with Null Values using arcpy.da.UpdateCursor of ArcGIS for Desktop?

How do you calculate fields with null values? I have multiple fields that may have null values, that aren't being calculated in the third field. import arcpy with ...
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1answer
10k views

Find and replace, field calculator

Can someone show me a very simple find and replace in field calculator for just one or two characters in a field based hyperlink?
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1answer
4k views

Concatenating fields using VBscript in ArcGIS Field Calculator?

I'm trying to get one column of text to move into another column that already has text. I DON'T want to replace it, I want the transferring text to be added to the already existing text in a shp file ...
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1answer
50 views

Capitalizing The First Letter Of Each Word In Attribute Field QGIS

I have tried capitalizing the first letter of each string in my field/column called "COMMUNITY" by referencing this post: Capitalizing The First Letter Of Each Word In Attribute Field Particularly: ...
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2answers
139 views

Split a string between 2 characters

I have the following string in Arcmap: "Node 1_1234.23,Node 2_567.88,Node 3_45.25" I want to return the numbers between the "_" and the "," into three columns e.g "1234.23" in column A ...
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84 views

Generate a string based on an integer range

After some initial research, I was unable to find a solution for the following issue. I'm sure there's an answer to this question already floating around here somewhere, but hopefully someone can give ...
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4answers
419 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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2answers
368 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 ...
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3answers
1k views

Extract numbers from string field

I am trying to calculate field test2 with only the numeric values from a string field test. The entire script is like: def makestr(test) list=[] for s in test: if s.isdigit(): ...
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1answer
129 views

Extracting data from Address field using ArcGIS for Desktop?

I am fairly new to using python in field calculator and could use some help. I want to populate SitusRdType with RD or AVE or LN or ST or DR depending on the road type. I also want to just have the ...
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2answers
149 views

Using Python For a Field Calc

In AcrMap 10.2 I'm trying to add a field and run this script in Field Calc: !shape.isMultipart! to see if I have any multipart lines. I keep getting geoprocessing failures. I am clicking the ...
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3answers
287 views

Conditional Statement for attribute data

I'm trying to write a conditional statement that references another field within the same shapefile layer. I want it to only do so if the one field is " Null " and leave is alone if there is already a ...
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2answers
447 views

How to get a string from a Double with a fixed number of decimals?

I have a featureclass (in a File Geodatabase), with a particular field of type Double. I want to copy it over to a text field, so that only 3 decimal places are shown. For example: 34.78902345 ...
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2k views

Debugging ERROR 000539 from CalculateField in ArcPy?

I previously successfully used the sample code here: How to calculate Field using part of filename in ModelBuilder? # Import standard library modules import arcpy, os, sys from arcpy import env # ...
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2answers
243 views

How to select only areas bigger than x acres?

I would like to create a new shapefile from another area shapefile. The new shapefile should only contain all areas that are bigger than 5 acres (10.000 m²). How do I do this?
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3answers
616 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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2answers
92 views

Calculate field more wisely

I first classified firstCol into groups and then I want to give the groups with different weighted values in another field, SecondCol. I will need to give different weighted values very often. I find ...
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2answers
58 views

How to compute the distance from the current polygon centroid to another in QGIS field calculator?

There is layer with polygons. I want to save in new field distance of every polygon's centroid to centroid of one particular polygon. To do this I should write some expression like this: ...
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1answer
212 views

How to convert text to proper case using the field calculator?

I am working on a set of data that has over 40,000 records on ArcGIS and I want to use a Proper Case for several fields/columns on the table. Is there a Python or Java Script that can help me automate ...
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1k views

Using Python to field calculate Lat/Long with decimal degrees rather than meters

The below is a snippet of a python script that I am writing that basically adds two fields - Latitude and Longitude, then calculates them. I could use the Add XY Tool which gets me to the same point. ...
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2answers
188 views

How to generate random points from FIDs using ArcPy or ArcGIS Field Calculator?

I'm trying to generate a shapefile of random points using FID from the attribute table. My attribute table has 800,000 features and I only need a sample of 240. Is there a way to do it in arcpy or in ...
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2answers
123 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
537 views

python expression convert field to string and format with leading zeroes

I would like to create an expression using the field calculator in ArcMap to be able to convert an Int field to a string and add leading zeroes. I am able to do it in a python window with an example ...
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2answers
144 views

Calculate Fields from 3 different fields using ArcGIS for Desktop?

I'm using a shapefile of different vegetation and land cover types and I want to generalize to a simpler classification (ie. I only need to differenciate between young and old forest and open land, ...
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2answers
210 views

Field Calcuator to add percent using Python

What might I go wrong here is that I am trying to add percent. I use the Field Calcualtor and it keeps getting an error. I am opening the Table to add a field named Percent and then type this: ...
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1answer
409 views

Simple field calculator equation in ArcGIS 10.2.1 not working with python parser

I am trying to calculate a percentage in a field in a table. customers and total_customers are short integer fields. arcpy.AddField_management(tableSepSel2, "percent", "DOUBLE") ...
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2answers
2k views

Concatenating text and string in Field Calculator expression (python)

I'm trying to copy an attribute value from one field to another (sum of raster values), but I'm having issues in writing a functioning expression for a Calculate Field script. I'm adding a field ...
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1answer
70 views

How can I change all the entries in a field to be entirely lower case?

I have a field with a bunch of species names, but for a single species there a bunch of case combinations (e.g. Cat, CAT,cat). I want to make a new field which has all the entries in all lower case. I ...
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1answer
926 views

Using Python if/then/else to return value from either of two fields based on value of third using ArcGIS Field Calculator?

I'm trying to avoid manually inputting Begin and End engineering station values already inputted into a seperate field. I'm dealing with(4) fields: Begin_Sta End_Sta Beg_End and Station. The ...
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3answers
1k views

Automatically assign numbers to point file in various order in QGIS

I know how to automatically assign numbers to a new point files using the $rownum function in the field calculator. However it does it from the top-left over and down like reading a book. I could ...
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1answer
60 views

Recalculate fields value using ArcPy and Calculate Field tool?

Im not sure how to pass through a list of fields within the calculate field tool.I have a list of fields and each of them need to be divided by 1000. My code is as follows: import arcpy shp = ...
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2answers
80 views

Remove time stamp from date field using field calculator

I'm trying to copy the dates from a field called InspectionDate (date data type) to new field called CompletedDate (date data type) but I don't want the time stamp to be copied over. How can I copy ...
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2answers
131 views

“CountIf” or alternative function in ArcMap field calculator?

Within ArcMap 10.3 field calculator, I am looking to count the number of features in a column that match the current value, and output that count. Ideally, the output would look like this: Number ...
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2answers
140 views

Update multiple fields/columns in QGIS

I need to update fields in attribute table of a vector using QGIS. I use field calculator for each field, but i have too many fields (and too many vectors also) and i need to program the task. The ...
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1answer
375 views

How to copy same values to another field in attribute table in QGIS using field calculator?

I am trying to copy values from Parsel_ID to Parsel_NO using an equation ( look at pictures) in field calculator but it is not working. What is the problem and how can I success this task??enter image ...
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1answer
46 views

How to select different values from two columns through Select By Attributes?

I'm using ArcMap 10.3. I'm trying to select by attributes different values from two columns. I want to define the areas where Main rock is GRAVEL And Sub-rocks are : a. mudstone tephra loess b- ...
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1answer
66 views

Debugging Indentation error on Python Parser of ArcGIS Field Calculator?

Would anyone please help me find out why I get an indentation error in line 3 def calc(f1,f2,f3): remove_list = ['01ST', '02ND', '03RD', '04TH', '05TH', '06TH', '07TH', '08TH', '09TH'] if f2 in ...