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 Field tool to calculate on null fields

I'm using ArcGIS 10.1. I want to use the calculate field tool in ModelBuilder on a table where if field1 is null, it should take the value of field2. If field1 has a value then it should stay as is. ...
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2answers
133 views

Field Calculator, Conditional

I am trying to assign Value from one field of my Attribute table to a new field based on the 3d field.... The Code Block I am thinking about as follows: *def conditional (!FarmCateg!): if ...
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1answer
121 views

Extract characters inside parentheses in QGIS

I have a shapefile of the buildings on my college campus. It has a "name" field that includes the name of the building and then in parentheses the building's campus address (i.e. Health and ...
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1answer
359 views

Calculate field result is float with Arc tool, integer with arcpy script

I am trying to calculate a field for some points within a python script using arcpy functions. (This is calculating the percentage visibility from a cumulative viewshed, if that matters.) # Process: ...
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2answers
566 views

Type mismatch error in Calculate Field tool in ArcGIS 10.1

I'm trying to run a rather lengthy model (built in ArcGIS 9.3.1) in ArcGIS 10.1 and I'm recieving an error on a Calculate Field tool. The error is - Type mismatch: 'iif'. This error is refering to ...
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3k views

ArcGIS 10.0 \ arcpy - CalculateField_management : help with syntax for updating text in attribute table of feature classes

I am trying to add (ie "Author", "LastUpdated") to feature classes within a gdb and then populate each of those fields. I have been able to get my code to run properly for the numerical field but I ...
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2answers
702 views

Trimming Specific Text Values in QGIS Field Calculator

Sorry if this is a dumb question, but I am wondering if there is a way to copy the text from one field to a new field, but eliminate specific words. For example: **Old Field** ...
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2answers
92 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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3answers
75 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 ...
2
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1answer
146 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 ...
2
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1answer
121 views

ArcMap Python Question: Trying to Field Calculate Slope Percent in to Text

I have a layer of polygons that I spatially joined to a raster to point layer of slope percents. My polygons now have the percent of slope in a field called Avg_point. I want to use the field ...
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1answer
474 views

ArcGIS 10.0, Field Calculator Nested “if” statement with strings

I need to assign a value depending on other two columns "FNP" and "Teilort". I wrote this script in phyton for field calculator. It actually works (no error messages) but the results in every cell is ...
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1answer
75 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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2answers
365 views

Convert from Julian Date to Calender Date in Field Calculator

Does anyone know of a way to convert from a Julian date to a regular calender date in either QGIS or ArcGIS field calculator? Thanks...
2
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2answers
143 views

Conditional field calculator expression

I need to calculate the PIPEID field to equal the G_KEY_COMP field if PIPEID is null or PIPEID and G_KEY_COMP do not match. I think the first condition of the PIPEID being null is covered by the ...
2
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3answers
113 views

How to write FIDs of points within each polygon to polygon field?

I have two feature classes one with points one with polygons (in ArcGis 10.2). Now, I want to write into a String Field of the polygon layer a list of all the Point-FIDs that are within each polygon ...
2
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2answers
359 views

Capitalizing The First Letter Of Each Word In Attribute Field

Does anyone know of a way to capitalize the first letter of each word in a field in an attribute table? I am doing this in QGIS. I know of field calculations to change all the words to Lower or ...
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1answer
433 views

Am I over-complicating adding and then calculating fields? Suggestions for a better way? (Python)

I'm attempting to re-position a question I asked yesterday here. I am starting to think that the way I wrote my code just isn't the best way. Am I overcomplicating things? I know for a fact that ...
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1answer
579 views

Field Calculate Degree Minute Second in Different Format

I have a field that is in degree minutes seconds, populated from ET Geowizards COGO Inverse tool. It populates the values as 90-12-28.15 where 90 is the degree, 12 is the minutes and 28.15 is the ...
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1answer
537 views

Field Calculator operation is not working

I've done this 100s of times and I can't understand why it won't work! I'm trying to copy the first 8 digits of from a HUC 12 (Hydrologic Unit Code) to a new field, which represents a larger ...
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1answer
1k views

Summing Attributes from a Related Table?

I have a line feature class representing road segments, with each road segment having a unique ID. This feature class has an attribute of average observed daily traffic counts. I have another table ...
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1answer
640 views

Does QGIS support parsing of date strings in tables?

It is straightforward to load GPX files (GPS downloaded tracks / points) into QGIS, then save and manipulate them as shapefiles. However, the recording date (in the comment (cmt) field) of waypoints ...
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2answers
57 views

VBScript - If/Then Statement - Field Calculator

I am trying to do a simple (or so I thought) if/then statement in the ArcGIS field calculator. I am trying to add the HydroCode field - hydologic soil codes - to an existing data set. I know what the ...
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3answers
86 views

Prefixing multiple values within QGIS using the Field Calculator?

I have a column in my my attribute table that contains a series of individually numbered locations. I wish to prefix all of these numbers with a letter, this letter will be the same for each of the ...
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2answers
68 views

select parcels in polygons and add fiels depending on the polygons

I have a lot of feature classes (results of service area with different polygons (0 to 10/ 10 to 20/ 20 to 40 and 40 to 60) (figure 1) Also i have a shapefile with a lot of parcels (figure 2) ...
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1answer
49 views

Add a certain number of days for a date field

I have one field for a permit decision date, and then I have another field for 180 days from that permit date. The permit date field has data entered, but the 180 day field I would like to calculate ...
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1answer
82 views

Subtracting columns (that include null values) in ArcMap Field Calculator

I’m desperately trying to run a very simple command where I subtract one column with others. However the problem is that some rows have NULL values, therefore the result of subtracting is also NULL. ...
2
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1answer
70 views

Converting Aspect degree to westness

I have extracted Aspect values in degree from DEM in ArcMap 10.2 full license. I want to investigate effect of Westness in my model so I was using conversion formula of Folded Aspect : ABS (180- ...
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1answer
51 views

Referencing fields in code block of Field Calculator in ArcGIS for Desktop?

I'm trying to use values from a field to fill a new field with a truncated version. The 'str.rindex' function is working out well, but I can't seem to figure out how I'm supposed to reference the ...
2
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2answers
96 views

Returning value from other field, using FieldCalculator

I am very new to Python and need what I believe is a very basic script in order for my field to represent another fields' input, if the field's value is 0. I tried to search for this, but gave up ...
2
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4answers
207 views

Field Calculator Python Expression Issues

I'm pretty new to Python and this is my first post on this forum so I could use some help. I am currently attempting to run some code in the Field Calculator in a model in order to replace string ...
2
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1answer
329 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 ...
2
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1answer
86 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.
2
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1answer
631 views

How to compare string fields in the same table with ArcGIS 10

I don't know exactly if there is a tool for this or a maybe a python script could be more suitable. I want to compare string elements from a field (POI_NAME) with another string element in another ...
2
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1answer
137 views

Replace characters

How to remove a special number of characters of a string, e.g. the last 7 characters? And how to join them as the first characters to the string of another field? Thank you for VBS and Python synthax ...
2
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1answer
97 views

Decimal Degree data erases itself between edit sessions in QGIS

I have a shapefile with point data. I calculate the $x and $y of the points successfully I save the changes and close the edit session. Once I reopen the attribute table, the data after the decimal ...
2
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2answers
170 views

python add fields that may have NULL values

I would like to use python to calculate a field (short integer) using other fields (short integer) present in the table. In some cases these fields may have NULL values for one or more of the fields. ...
2
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1answer
106 views

Arcpy Calculate Field Formatting Syntax

I am trying to field calculate a double field (PID) to a new string field (PIN). Using: qry = '"139-{}".format(!PID!)' arcpy.CalculateField_management(out, "PIN", qry, "PYTHON") Given a PID = ...
2
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1answer
544 views

How to copy values from field to another using arcpy?

Can some one please let me know how I can do simple field calculation like Copying From "A" to "B" in ArcPy? I have found lots os example on web which they all used extra expression and they were ...
2
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1answer
109 views

Populate an attribute table field using the 'startswith function

I am hoping that someone may be able to help me. I am new to ArcGIS, and even newer to Python. Working in ArcGIS 10.1, I have done is created a new text field in an attribute table, which I have ...
2
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1answer
736 views

Calculating a field based on two other fields, if they exist [duplicate]

I'm using ModelBuilder to iterate through ~800 shapefiles to add and calculate a new field (I'll call it Field_A). Field_A needs to be populated by either Field_B or Field_C, whichever exists. Half of ...
2
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2answers
2k views

Use Feature Class “Name” from Iterate Feature Classes to Calculate Field with Model Builder 10.1

My goal is to create shapefile that contains merged feature classes from a geodatabase. I would like for there to be a new field in the resulting shapefile that contains the name of the original ...
2
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1answer
272 views

Need a Python field calculation that works like the DatePart( ) VB Function

I have a field called Abandoned Year (short integer data type) that I am trying to populate with a four digit year from a column called Decommission Date (Date data type). I have done this in the ...
2
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1answer
149 views

Syntax for ArcGIS ICalculator object?

I have a code snippet that I can't figure out: 'Define a calculator for NewArea field pCalculator = New Calculator With pCalculator .Cursor = pCursor .PreExpression = "Dim ...
2
votes
3answers
835 views

Field calculator script not working

I am trying to do the following in the field calculator in ArcGIS 10 if [IncdStDir] = " " then [IncdStNo] &" " & [IncdStName] &" " & [IncdStSfx] else [IncdStNo] &" " & ...
2
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2answers
2k views

Recoding values based on contents using ArcGIS Field Calculator or Python?

Is there a convenient (or even effective) method for recoding field values using the field calculator or standalone python script? In this case, I am given several unique strings to identify a type ...
2
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1answer
42 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 ...
2
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1answer
275 views

Converting values in datetime field to strings in text field using Python parser of ArcGIS for Desktop?

In the attribute table of my file geodatabase feature class I have a populated field called DateField of type date, and a text field called TextField. I have not yet hit on a way to convert the ...
2
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1answer
77 views

Add or subtract days to date field using the field calculator

I am using ArcGIS 10.1 I'm not a programmer I want to use the field calculator to add 4 days to the current date if the status is "delivery" or subtract 5 days if its status is "order" this ...
2
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2answers
82 views

ArcGIS Field Calculator passes European-formatted floats as tuples

I have the problem that the ArcGIS Field Calculator doesn't read a float number when it is included in Python by referring to the field that contains it, in this way: def giveResult(floatValue): if ...