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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ArcGIS field calculator: Calculating a new field using multiple fields with python

Basically, I have a large polygon data set that has soil data for an area and I want to assign numeric values to the data based on soil texture text values (e.g. SIL=4, CLY=7, ...). However, the soil ...
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2answers
247 views

Cannot convert string to int using ArcPy Calculate Field

When I load a csv file to join with ArcPy, it converts all string fields that are numeric to integers. Therefore, I have to add another field within the feature class that I'm using for joining that ...
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112 views

Calculate field based on other two added fields in ArcGIS Model Builder

I have a model in model builder where I add 2 fields, "field 1" and "field 2". For each field I calculate their values using the calculate field tools. Afterwards I add a third called "Field 3" of ...
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70 views

Use Python in Field Calculator to increment up value

Please see screenshot for field calculator Python logic. I have no idea what I'm doing that's any different from this GISSE answer. The error I receive is ERROR 000989: Python Syntax Error (invalid ...
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basic problem using division in field calculator

This is a very basic question, but I can't figure out what's going on. I've got election results I'd like to simply display as percentages rather than vote totals, which should be as simple as ...
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102 views

new layer from calculations with fields of other layers in QGIS

I've two layers, both with the same fields: A, V, where A is the shape's area and V a value given by me. I want a new layer with shape created by the intersection of the other layers' shapes and a ...
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1answer
27 views

Create field on open ArcGIS map - not saved

I am using ArcGIS desktop with an SDE feature layer with enterprise data that I do not have rights to edit. The data changes weekly but I need a field that is sum of 2 current fields without creating ...
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3answers
2k views

calculating a field in which null values may be present

I would like 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. For example, ...
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70 views

Line length for line files

Using QGIS, Brighton 2.6. Trying to calculate line-lengths for linear features (roads, trails, fenceline) and used this post (How to find line length in QGIS while editing?) and the links associated ...
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1answer
444 views

Calculate Field in ModelBuilder gives General error executing calculator. ERROR 999999: Error executing function. Expected end of statement?

I am attempting to do zonal statistics for multiple images and I need to add an extra field that will have the name of each raster file in each row to the finally appended file. I have added a field ...
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2answers
184 views

Using Python in the field calculator - if/else over multiple fields

I'm trying to work out how to populate a field depending on the lowest score across 6 other fields. I've read several other questions relating to if/else statements but I'm only just starting to learn ...
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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 ...
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120 views

Setting field equal to raster Name ID for batch process in ArcPy

I am wanting to set an existing field called RasterID to the name of the raster for which the attribute table belongs to, but for a batch of rasters. Is there a way to do this with my current code ...
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2answers
153 views

How to pad field with blank spaces using calculate field tool of ArcMap?

I am trying to pad the right side of a field with blank spaces so that when I label the field, it labels further over to the left. The only way that I can seem to make this work so far is by adding a ...
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1answer
241 views

Populating a field in an attribute table with a consecutive number sequence? [duplicate]

I know that this is probably a very basic question but I cant seem to find an answer through Google searches. I would like to create a field in an attribute table (in ArcMap 10.2) for a Number Label ...
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1answer
100 views

Calculate values in one field based on values in another field

I have one field with Zoning Codes (i.e.: RS) and I want to update another field with the string "Residential Single Family". The new field is currently NULL, I would like to add the full text string ...
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1answer
82 views

Joined tables and now field calulator is greyed out

In ArcMap (10.2), I accidentally calculated the wrong field outside of an edit session, so there was no way to reverse my action. I restored a previous version (shadow copy) and joined the tables ...
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328 views

How to find if polygon has a hole using field calculator in ArcGIS

Some 3rd party software cannot handle polygons with holes (donut polygons). To find them I always use ArcView 3 field calculator, because: however when I try to do this in ArcGIS, I get this: So ...
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38 views

Sum a field, and take that sum and use it to populate an existing field in the same table

I am trying to break down land uses in a watershed by making a tool in ModelBuilder. Right now I am clipping a land use layer by a watershed polygon, dissolving land use layer by land use code, ...
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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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3answers
457 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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2answers
2k views

Forcing decimal numbers to use comma in ArcGIS Field Calculator?

Can I add the comma "," to force the decimals to remove from the attribute and replace with the number? For example, I have an Acres field column that says 506320.0750 and I want to replace the ...
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1answer
64 views

How to fill column with several conditions using QGIS field calculator?

I know the synthax in order to fill one field with only one condition (field calculator): case When "attribut" = 'value' then value End But how to do populate automatically one field with ...
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256 views

Calculating file name with field calculator

Is it possible to calculate the file name in an attribute table? My shape file has a name like "cities.shp". In this shape file I want to have a attribute "cities").
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1answer
76 views

Multiply whole column with the field calculator in QGIS

I have a layer with the field size. I did some mistake with the value and now I need the values multiplied by 16. But instead of going through 500 lines and recalculating them I would like QGIS to do ...
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1answer
31 views

How to update the value of a field dependant upon the the fields ID in QGIS Field Calculator

I am looking to create links to website pages and to automate the procedure a bit more I would like to have a standard link followed by the ID of each field. For example, I would like the standard ...
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107 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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1answer
66 views

Changing field values using arcpy

Say I want to make my field buff_dist longer than by 400ft, I want to write a code that will go through the table and change the field value by adding 400ft to it's value. How would I write that? I ...
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1answer
536 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 ...
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1answer
160 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 ...
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1answer
316 views

How to classify time periods in a new field, using Python?

I have a datetime field (Horario) in my feature class, showing only the time. Although the date doesn't appear, it seem to be stored automatically as 30 Dec 1899, I'm not sure why. I want to use ...
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1answer
157 views

Are Date columns in feature classes stored as python datetime objects?

I have a Date column called readings_measurement_tstamp stored in my feature class. I would like to add a String column to this feature class and Field Calculate it to be be just the %H:%M:%S ...
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1answer
38 views

Adding formula in field calculator when new attribute is text type?

I added a new text attribute to my table. I would like it to print the values "y" or 'n", for when an attribute in the table is other a specific cut off it will code Y, and then that attribute is ...
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1answer
275 views

Calculating Percentiles in ArcMap?

I have a large polygon dataset (26,000) records with numerous attributes columns. I wish to calculate the percentile rank of each attribute. Say I have population_density in an attribute, is there a ...
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1answer
394 views

How to calculate unique IDs starting from highest current ID

I have been using a python script in field calculator in ArcGIS 10.2 to add unique IDs automatically, however there are two things I would like to improve this process: Each ID also has letters at ...
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1answer
194 views

Concatenate Multiple String Fields and Convert to Date field using ArcGIS Field Calculator?

I'm Working in Model builder using the calculate value tool. I have three columns - SignatureDay, SignatureMonth, SignatureYear - All three are string data types and all consist of just numbers for ...
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873 views

ArcGIS Field Calculator Python numbering rows of fishnet

I have a grid of 100*100 cells. I want to add to each cell a number representing the row it is in (like in excel). I added a field and want try to solve that with field calculator: The code is ...
3
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1answer
627 views

Using Python in Field Calculator to compare two fields

I'm trying to use field calculator to compare two fields in a table of tax parcel data, Land Value (LAND_VAL) and Improvement Value (IMPRVT_VAL). My goal is to determine (1) Parcels with land value ...
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118 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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99 views

How to perform If Statement in Field Calculator of ArcGIS for Desktop? (Python or VB)

I've one field "MAXSPEED". I want a Field Calculation that will calculate an additional field ("noise"): If MAXSPEED > 40 then the term: (73.5 + Log ( 25 ) * ( [MAXSPEED] / 50)) should be used to ...
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41 views

QGIS upper round in field calculator

I need to to in the field calculator the following calc: toint(Field1 / 25.0) but i need to round the result to no decimal places but upwards. Exmaples: If 17/25 result should 1. If 25/25 result ...
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63 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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3answers
72 views

VB Script field calculator - error with conditional statements

I have limited VB Script experience, but have been working on the script below and keep getting errors, the most common being "expected identifier". Can someone tell me what I'm missing here? Dim ...
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1answer
147 views

Can you use wildcards for column headers in Field Calculator?

I know you can use wildcards for fields like so (in the Field Calculator): case when "column" ILIKE '%example%' then 1 else 0 end Can you do something similar for the column headers themselves? I ...
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4answers
463 views

Auto populate field with text using field calculator if/then

I've extracted values from a raster to a point file, but now I need a field with the text information from the raster attribute table that corresponds with the value. I've been trying to use the field ...
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1answer
72 views

How can I refer to two tables in ArcPy's CalculateField_management? [closed]

I tried to refer to the different table's fields just like I saw in How to Calculate Field in joined table using ArcPy? but it doesn't work. There are two tables in my example. I have created table ...
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23 views

How to use calculatefield_management with ArcPy and joined second table? [duplicate]

How can I use calculatefield_management with ArcPy if I have a joined second table? I want to go through the attached table's field and I want to get records where the certain fields is. How can I ...
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What fields can the CalculateField_management expression parameter contain?

What fields can the CalculateField_management expression parameter contain? I mean the parameters can be the fields what are in the output table, or can they be a field of another table too? There ...
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1answer
2k views

How to Calculate Field in joined table using ArcPy?

I have to calculate a field based on another field in a joined table, but an error occurs: "Parameters are not valid. ERROR 000728: Field !Table_A.field_A! does not exist within table" My code: ...
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1answer
748 views

Why is using two imbricate UpdateCursor not working?

I hope my question is not redundant. I wrote a script to Update a table using two imbricate cursors. The goal was: to read a records, update some of its values Make a selection based on this ...