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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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
216 views

Why is this field calculator expression evaluated incorrectly when using Python syntax?

I have a polygon featureclass containing an integer field 'gridcode'. I've added 2 new float fields VB_calc and Python_calc, both of which should be equal to gridcode / 1,000,000. If I calculate the ...
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1answer
266 views

Concatenate multiple string / text fields some of which may have NULL values ArcGIS

I am trying to repeat the behavior of this code from the ESRI website. I want to replicate the output example in ALL_Type field, so that it concatenates a field but it deals (ignores) any that have ...
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1answer
69 views

Calculation of a text value, The value of which is separated by a special character

How can I calculate a text value, the value of which is separated by a special character? For example: dog | duck, I would like to keep the first value: dog or elephant | cat, I want to keep ...
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1answer
323 views

Adding an “m” to the end of every number in a row

What function do i need to use to add an space and an m after every item in a row, using the field calculator in the attributes table. I have a load of numbers (as strings) and would like to add m ...
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1answer
77 views

How to convert unix time to qt time type?

How can I convert unix timestamp to qt time type using qgis field calculator? I would like to avoid importing my table into excel and convert the timestamp to qt time type.
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1answer
238 views

Python Syntax Error when running Python Snippet of successful geoprocess

I am having an issue with a simple python snippet. Here's the background: I wanted to include an additional step in a nightly update script that replaces characters in a field that simply do not play ...
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1answer
260 views

Python code in Field Calculator gives General error executing calculator ERROR 999999: Error executing function?

In a shapefile, I have Field named Elevation with a text field containing integer ranges stored as strings: 1 - 2 3 - 6 2 - 3 8.5 - 12 11 - 12 I need to categorize it using rule that if Elevation ...
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0answers
229 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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1answer
112 views

Field Calculator If/Then in ArcGis 10.1

I've been looking through these threads, i found something similar and thought it could be the answer, but it doen't seem to work for me... I could do this the slow way with Select By Attributes, but ...
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183 views

How to calculate percentages using QGIS field calculator expression?

I am new to QGIS. I am wanting to calculate a field using other fields and some operators. Here is my expression: case When "RVM_CAT" = 'B' OR "RVM_CAT" = 'C' Then ("PC1" /100) * "RE_ha" When ...
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3answers
884 views

Setting Zero values back to NULL

I'm working with ArcGIS 10.2 for Desktop and OS Windows 7. I need to set numeric vales from Zero back to NULL, but I can't from the field calculator. I'm working with a vector file and I need to ...
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0answers
85 views

calculating decimal degrees from coordinates found in an excel table

What is the exact syntax to use when calculating decimal degrees in the field calculator? I know the general formula {i.e. Degree + (minute/60) + (second/3600)} but how do I put this into the gis? I ...
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2answers
323 views

Calculating the average / MEAN of an attribute field in a QGIS model

I need to know how to calculate the average / mean of an attribute field in my point shape file. Is this possible to do with the field calculator? I just found the options min or max but not mean. The ...
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0answers
31 views

How to get Subtype name in Field using field calculator [duplicate]

I would like to get feature subtype name in another field using field calculator. Any one can advise to make this success? I am expecting ".Cal" file code using with Field calculator.
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1answer
90 views

Populate field with current time

I am trying to populate a field with the current time. Here is what I tried that did not work: Start editing Open Attribute Table Add Field -> Name: time Type: Date Right Click on Field Name ...
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2answers
2k views

Arc 10 field calculator scripts

I need scripts for the field calculator that: extracts the first word from a column, i.e. "Jones School" - "Jones", and A script that will capitalize this new field, "Jones" - "JONES". This is Arc ...
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1answer
88 views

Problem with Python codeblock recognizing a field

'<'First Post Alert> I've been through multiple iterations / gyrations, and while there may be multiple problems here (and I'll appreciate feedback on all of them), the recurring issue is that the ...
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2answers
141 views

Calculate Field Syntax: If statement over many fields

Apologies if this has already being asked but I couldn't find a page pointing to this problem. I'm struggling with the python syntax in the Calculate Field so that, in the table above: if b, c, d, ...
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8answers
10k views

How to Remove return/newline (\n) character from Field using Python and Field Calculator?

I have a geodatabase table with a field that I'm trying to remove return characters (new line). I found this post (How can I remove (chomp) a newline in Python?) of how to do it, however it is not ...
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1answer
215 views

How to SUM field and then insert into NULL column?

I am only in the beginning stages of learning Python. I have a column, 'QUANTITY_SOLID', that I want to take the sum of all of its rows. I understand I can do this with 'SUMMARY_STATISTICS', but i'm ...
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0answers
111 views

Warning 000405 when trying to calculate field [closed]

I am trying to create a model but am getting hung up on my first step. I need to calculate an ID field from an FID field so that I can join it to another table based on the ID field. So I have a ...
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1answer
2k views

How to convert state name abbreviations to full names?

I have a data table with columns that includes city names (ex: San Jose) and state name abbreviations (ex: CA). Is there a way to define the state names as their full names (i.e., CA = California) and ...
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1answer
65 views

Sum a field in buffer intersection

I have looked and do not see this answered in any other discussions. Purpose: Site suitability analysis for brewers spent grain processing facility Method: Locate intersecting buffers with greatest ...
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1answer
85 views

How to find and replace a singe word in a string?

How do i find and replace a single word of a string? e.g. Calle Iparraguirre to Iparraguirre I've tried: replace( 'Calle\\s', 'Calle\\s', '') replace( "name",'calle','') and all combinations ...
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2answers
70 views

assign a number for each group in field calculator

I have several thousand features each of which has a name. The names are not unique. what I want to do with the field calculator is assign a number to each name so I can refer to a number and always ...
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1answer
62 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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1answer
2k views

Writing conditional (if/then) statements into Field Calculator of ArcGIS for Desktop using Python parser?

I have gotten stuck on another seemingly simple arcgis field calculator python expression. I obtained a great answer to a another similar question a few years ago: Python Field Calculator ArcGIS 10 ...
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1answer
35 views

Filling Field2 to icorresponding values in Field1 of shapefile using Field Calculator of ArcGIS for Desktop?

I have to give explanation in a new field of the existing field which contains abbreviation. Example: Field "Geology" has values Q, Qs,N....(abbreviation), I have to give explanation of those in a ...
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1answer
118 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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0answers
26 views

Assigning values to new field using field calculator? [duplicate]

I have a polygon with attributes showing the service area of 300m from a busstop as well as 600m from a busstop. Attribute fields > From Break with values 0 and some with values 300 Attribute fields > ...
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1answer
5k views

How to do a simple find and replace in QGIS field calculator?

I'm trying to replace selected string values in an attribute table, eg. "Text1" for "Text2" (QGIS 1.8.0), patriculary for those rows with NULL values. I have been trying to use the replace expression ...
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3answers
172 views

Debugging CalculateField_management ERROR 000623: Invalid value type for parameter field?

I am trying to select records in my table that have certain words in the "Name" field and then code them as 0 (not pharmacy) or 1 (pharmacy) This is just a test searching for two words to select ...
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2answers
59 views

Field calculator fails when computing First X coordinate in ArcGIS10

I have this line in python to compute First X coordinates into the Field Calculator from each polyline: !Shape!.firstPoint.X Then, when I inspected the attributes I see this rare thing: You may ...
5
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1answer
374 views

How to use %value% (from For iterator) in SQL expression of Calculate Field in ModelBuilder?

I have a shapefile with data of fish specimens and the coordinates where they were tagged for research purposes. One of the fields in the attribute table of these shapefiles is the fish length in ...
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1answer
72 views

How to return end of string up to a certain character using Field Calculator?

I am trying to accomplish this task: http://stackoverflow.com/questions/15851568/how-to-get-the-last-part-of-a-string-before-a-certain-character within the Field Calculator. I have the below but ...
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1answer
55 views

Field Calculator not showing some fields

When I open my attribute table, click on a column, and select Field Calculator it opens and doesn't list all of the Fields in my attribute table. Why can't Field Calculator find these Fields?
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1answer
148 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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1answer
188 views

Extract one GPS fix per day from data?

I am in the fortunate position of having 2 years worth of animal movement data. With such a large amount of data I would like to extract only one fix per day to make it easier to work with. Data = 14 ...
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0answers
53 views

Field is not nullable but Field is nullable Box is checked

I had this problem already a couple of times. I add a Field (float) to an existing feature class, the Field is Nullable is arleady checked. But performing a calculation with the Field Calculator on it ...
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1answer
166 views

ArcMap Calculate Field..if “text” in !Field!

Is it possible to use Field Calculator in ArcGIS to add text to a new field based on an if in statement? Example: In an attribute table I have a some fields called !X!, !Y!, !Z! where "A (xx%)", "B ...
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1answer
80 views

What is the syntax for Python 2.7 to permanent display in percent in a field column?

What is the syntax to build to calculate field, for example, Acres to Percent? 841173.00 to 82 % What I want the field column in Percent to be display numbers with percent with the alignment to ...
5
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3answers
115 views

Calculation based on features in shapefile

I hope I get the terminilogy right! Correct me if I mess something up. I need to perform some calculations for a scoring system for different habitat types. The Problem is that I have two different ...
2
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1answer
105 views

Randomly choosing one from multiple fields in Field Calculator of ArcGIS for Desktop?

Using the Field Calculator in ArcGIS for Desktop, I want to randomly choose one field from a list of 10 fields (strings). The Excel equivalent, which is working, is: =INDEX(A2:J2;rnd()*10+1). How ...
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2answers
179 views

Expression to calculate and sort data from several layers into one layer

I am trying to develop an expression whereby one layer can add data from 2 other layers and then rank them, is this possible? I have also tried the problem with using just 1 layer but I cannot work ...
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41 views

Interaction with two variables as parameters, saving the raster properties output into a table (.dbf)

The draft of the model below TASK: I need to calculate the percentage of river channel that is covered with shadow in each timestep RESOURCS: I have values for azimuth and elevation of the sun ...
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82 views

Calculating Area of Raster Classes

I have a raster in a GRID format that was created by Image Classification. The GRID is projected in StatePlane meters, but I would like the area in square feet. I'm assuming I will need to use the ...
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5answers
183 views

Calculations in if statement

I want to perform a simple calculation with the Field Calculator using this piece of script (note that all the elif statements are attempts for another syntax and non of the worked): def ...
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4answers
64 views

Populate a field from another field with a conditional

I am working in SDE geodatabase where I have a feature class 'Mange_Waste' and "Q1", "Q2" are two fields. I wanted to use python script for populating "Q2" from "Q1" with a condition. Like, if the ...
2
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1answer
102 views

QGIS: Expression WHEN property1 = 'FOO' THEN property2 = 'BAR'

Our Foundation is adding additional properties to points. If property1 = FOO , then add property2 = BAR WHEN property1 = 'FOO' THEN property2 = 'BAR' END When I run this the ...