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 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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225 views

Updating new field from existing field using ArcGIS Desktop?

I need to update my new field/column (Property Type) with either "detached", "semi", or "terrace" depending on an existing column (Property Count): where the count = 1 I need to populate Property ...
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3k views

Selecting by attribute and calculating field of new selection in ModelBuilder?

I have a polygon shapefile (with 4000 records in it) that I want to group into different regions by doing a "select by attribute". I need to do this about 164 times because of the different selection ...
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224 views

ArcGIS python “add field” and “calculate field” workflow

I am new in Python and I am creating a Script. I've crafted a functional code, but I'd like to know if there is an easier way to do it, just for curiosity (And learning new ways!). The purpose of ...
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3answers
85 views

Can't replace attribute with field calculator

I have an attribute table where one of the columns (laeskaerm) has been edited/created by checkboxes on 2 different machines. Result: it contains both 1, 0, true, false and NULL I'd like to replace ...
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89 views

Averaging XY data for locations in QGIS

I wanted to find out mean of the selected point using QGIS. I tried out selecting using attribute table but could not find an option for mean in field calculator. I have attached a screenshot with ...
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223 views

QGIS - Is it possible to increase Output Field Name?

When creating a new Column, the default value for the length of the name is 10. Using the Field Calculator via the Model Builder, I want to include the names of regional areas into the columns which ...
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1k views

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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754 views

Adding VBA into a Python script generated by ModelBuilder

I have created a model that does a calculate field and have used VBA in the code block. But when I export it to Python, it doesn't work. Here is the VBA code: new_value = [HDATA_N_LAREF_ACTIVITY_TEXT]...
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Populating field with max M value of feature using Python in ArcGIS Field Calculator?

I need to calculate the max M value for a line feature using Python in ArcGIS 10 Field Calculator but I cannot figure it out. In 9.3 I used the follow VBA expression… **Pre-Logic VBA Script Code:** ...
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75 views

Python to create new fields in many layers / QGIS

I have a number of line layers on which I need to perform the same task: add 4 columns with the start and end points of each line. The expressions that I use to do this are: $xat(0) $xat(-1) $yat(0) ...
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39 views

Using ArcGIS Field Calulator with VB Script

My code looks like the following: if [LWS50yrp] <136.5 then [DMG_50y] = 0.1 elseif [LWS50yrp] >=136.5<154 then [DMG_50y] = 0.15 elseif [LWS50yrp] >=154<166 then ......
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94 views

Replace non-ASCII characters in QGIS Field Calculator

I want to replace all non-standard characters from fields in a dbf table in QGIS. From http://stackoverflow.com/questions/20078816/replace-non-ascii-characters-with-a-single-space I see we can use ...
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2answers
46 views

Describing input field in ArcMap Field Calculator window?

A few days ago I was answering Comparing two fields and printing result as 1 (if number matches) or 0 (if not) using Python Parser of ArcGIS Field Calculator? When describing the process required ...
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131 views

QGIS Field Calculator functions

Using QGIS 2.12.3, within the Field Calculator "Geometry" section, there are certain functions, such as "area", that also have a corresponding term beginning with a dollar sign, i.e. "$area". I don't ...
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Why is VBS If Then Label Expression not working?

I am trying to label a field based on other field. For [TYPE] = "PRIMARY", the [LABEL] is having this structure: "TAN80901B" For [TYPE] = "SECONDARY", the [LABEL] is like this: "TAN80901C/D20b" I ...
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115 views

Reclassifying a polygon using ArcGIS field calculator?

I am trying to reclassify a polygon into three classes: 1 and 2 = 5 3 and 4 = 3 5 = 1 I have been trying to do this by calculating a new field in the attribute table but I am very ...
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203 views

Which python function should I use to populate a string field based on a numeric value from a numeric field in ArcGIS Field Calculator

I am new to Python and I'm trying to write a simple if then statement in Field Calculator in ArcGIS 10.2.2 that will take the values from a numeric field and add them to a string field. I can't ...
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2answers
294 views

How to remove a certain number of digits from the front or end of an attribute field?

Can I use the filed calculator in QGIS somehow to remove the first 4 numbers in all attribute fields in a column? Example 16011234 -> 1234 EDIT: Silly, I can just subtract with 16000000 in this ...
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1answer
2k views

How to Calculate Cumulative Field Values in Arcmap

My problem is conceptually quite simple; In Arcmap 10.2, I wish to create a field which contains the cumulative values of another field in the same attribute table. For example, if the first three ...
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How to Populate new field using expression containing MAX value from another field in ArcGIS attribute table using field calculator?

I've got one field X with 10 numerical attributes (float/double). I've created a new field Y (also float/double) which I need to populate with the percentage of each record/attribute (in each of the ...
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315 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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1answer
134 views

Field calculator uses wrong fields when working with joined data

I am having an issue in qgis table joins. i have a joined a csv file to a sqlite database and common id is used for join. the join is displays correctly in attribute table. the attributes in sqlite ...
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1answer
2k 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 ...
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852 views

How to create button that calculates acres on selected polygon features?

I'm looking to create a simple button that calculates acres on selected polygons and can't quite find what I'm looking for. I read through this thread: automating a python script..., but found it wasn'...
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607 views

Measurement units not returned in project CRS units

I am attempting to calculate area of country polygons using the field calculator. The layer in question is unprojected WGS84, but I have set the project CRS to World Equidistant Cylindrical (Sphere),...
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56 views

How to split string (the last digits) in QGIS?

I´m working with QGIS 2.12. Is it posible to split string "from the right side" (it means I needed the last text from every field)? In one field I have description like: new street 25 old street 2 ...
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50 views

How to convert a “yyyy/mm” field to “yyyy/mm/dd”?

I am trying to edit an existing date field of the form "yyyy/mm" to a format that the TimeManager Plugin for QGIS can handle - I guess "yyyy/mm/dd" will do it. I've got as far as opening the ...
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2answers
124 views

Using ArcGIS Desktop field calculator (python) to parse date

I'm trying to parse a datetime field using python (but have never used python for it before). I have a field that contains a valid date, but not a valid time... and other fields that have valid hour ...
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1answer
83 views

QGIS field calculator returning results in different units?

I am trying to use QGIS to get the perimeter, area, bounds width, and bounds height of US congressional districts, using the US Census TIGER shapefile. I loaded the shapefile into QGIS, set my CRS to ...
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50 views

add text value to attributes

this is a novice question I have an attribute field that's missing a piece of information, i'd like to amend the attribute field like below: This is the current attribute field: "V:\Building & ...
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118 views

Field Calculator Script

I am looking to check how up-to-date a feature class is by using our latest parcel update. I am wanting to check "owner" field with "Owner_1"...I am using field calculator to grab the last name in "...
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1answer
294 views

Accumulating values of date field using Python parser of ArcGIS Field Calculator?

I would like to modify the following accumulative/sequential python code sample in field calculator in a Date Time field. I think this is the correct code to use but let me know if not. The Date Time ...
3
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1answer
425 views

Using arcpy and script toolbox to add the date to a attribute table

I would like some information on how to add a date to an attribute table, by adding a user specified date in a script tool that will update the polygons attribute table. In short I have two polygons ...
3
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1answer
206 views

Trouble calculating areas in QGIS using field calculator

I am testing various projections to calculate areas using ICES statistical shapefiles and the QGIS field calculator. I am using ICES areas downloadable from the following link: http://geo.ices.dk/...
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1answer
527 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
181 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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ArcGIS 10 Field Calculator [closed]

I'm new to GIS in general and field calculator in particular. I have a basic attribute table with three columns. I'd like to assign values to column C based on what is in column A. If Column A = 8 ...
3
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1answer
1k views

Calculate Field python code has “Expected end of statement” error

I am creating a line shapefile from a csv in a Python (2.7) script. I am assigning an ID field from the csv to a variable and then later using it in the Calculate Field tool. The ID field originally ...
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2answers
4k views

Using Value from Iterate Feature Selection to Calculate Field in ArcMap 10.1 ModelBuilder

I have two polygon feature classes, an alignment layer and a parcels layer. I am trying to use ModelBuilder to create a tool that will do the follow: iterate through groups in a single field of a ...
3
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505 views

QGIS Field Calculator Results Removed When Saving Edits

Mac OSX 10.6.8 QGIS 1.8.0 : Using the field calculator from the attribute table, the $area of each feature is shown nicely in the table until I try to save it, then all the values are replaced by NULL ...
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856 views

How to make Field Value constant size (length) by appending zeros towards end?

How do I append my field values in my .dbf to correspond with the values of my feature's attribute table. I need to append 0's to the field value if the field value is less than 11 characters in ...
3
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1answer
73 views

QGIS find and then replace value in multiple columns

This is based on a previous question/answer that I had. QGIS -replace values in multiple columns I need it to update 3 fields now and I get an name 'e' is not defined error. What have I done wrong? ...
3
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1answer
44 views

Conditional Statement in QGIS Field Calculator

I'm using QGIS to calculate total loss in an earthquack attack. I wrote this expression in Field Calculator. CASE WHEN "build_type" = 1 AND "MMI" < 5 THEN "perc_loss" = 0 WHEN "build_type"...
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92 views

Calculate area of geometry derived from current feature in QGIS 2.8

I'm trying to create a new field defined as the area of the convex hull of the current feature, in the Field Calculator in QGIS 2.8. Calculating the area of the current feature is easy ($area), and ...
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42 views

How to replace a directory using QGIS Field calculator?

I have a column called Hotlink full of incorrect directories and I need to edit them. They currently read C:/ABCD/filename.pdf and I want them to read C:/Maps/ABCD/ABCD/filename.pdf The script I'm ...
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1answer
55 views

QGIS - Field Calculator: scale_linear gives unexpected result

When I try to use scale_linear, its output isn't as I expected. My values are from 1 to 16, so I set domain_min = 1 and domain_max = 16. I want to interpolate to interval from 1 to 4 so I set ...
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1answer
878 views

Why is arcpy.CalculateField_management() writing 1899-12-30 00:00:00 instead of expected date?

I'm using ArcGIS 10.3.1 for Desktop to test before writing an answer to How to enter date with arcpy.GetParameterAsText with arcpy? I have written the test code below that I am running against a test ...
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290 views

How to calculate distances in QGIS field calculator?

So I'm using qgis 2.6.0 and I have a csv (converted into a .shp) with two geometry columns, I want to create a new column with the distance between the two geometry: shot.lat shot.lon haul.lat ...
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2answers
419 views

Iterate calculate field in multiple tables in ModelBuilder

I would like to iterate calculate field in multiple tables using ArcGIS Model Builder. The figure below explains details of the calculations. My existing model calculates value only for the first ...