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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How to concatenate XY values in attribute table without messing up the numbers in ArcGIS 10.1?

Here's the procedure I use and the resulting problem I'm having. First I use the Add XY coordinates tool to add POINT_X and POINT_Y fields to the attribute table of a point layer. I then add a new ...
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306 views

Stuck updating one field based on the condition of another using Acrpy or Field Calculator

I have a shapefile with 5,000 city points. I need to populate a new field, "cls_pop", based on each cities population, so that cities with a population > 2,000,000 will have "cls_pop" = 1, cites with ...
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368 views

Stop rounding values in Qgis attribute table

I am calculating the areas of my polygons in Qgis using $area and everything works fine until I click on "save". All my values are rounded to an integer. I tired setting the output field type to ...
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501 views

area values determined with field calculator become null when saving

using field calculator in Qgis 1.8.0 to get the area, it shows just right at first but when I save it, the values become Null. help please
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1k views

Concatenate Fields into One Field in QGIS

I have seen some posts on this, but only for ArcMap. I am looking to take a range of values from two fields and concatenate them into one field to make a unique value. For example: XMAX YMAX ...
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470 views

FieldPyculator Plugin - How to Classify Fields?

Could someone tell me how to classify/populate fields with QGIS FieldPyculator Plugin? In the Attribute Table, I have a field named POPULACAO with population data: I want to apply a weight to ...
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270 views

Small issue with field calculator

What am I doing wrong in this field calculator logic? Pre-logic def re_score(elev_t,f2, contour): f2=contour if elev_t.endswith('.5'): f2 = "Midi" return f2 Expression for field "Contourtyp" ...
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347 views

How to tranform a column field into a list using Field Calculator

I'm trying to make a simple field calculation with ArcGIS 9.3: New field = Old field - Old field(first value) which in Calculate Field with python code should be Expression: !Old field! - first ...
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43 views

How to search for a specific field and then use it in Field Calculator

I have a piece of code where the goal is to search through the field names within a feature, select any field based on a specific character (in this case "z") and then use that selected field within a ...
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41 views

How to delete char in table attribute in QGIS 2.6.1

I need to label many items but in the table attribute field there are some char (#F) for every item that I have to delete. The length of the description are not always the same. I create a new field ...
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61 views

delete a space with the field caculator

I would like to delete the space in this number like this 'F00 089' with the field-calculator. Is theres a function in the field-calculator? ! see my screenshot
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56 views

Field Calculation Python acceleration of gravity [closed]

In my problem i have a column DISTANCE and a column TIME and i want to calculate with python in field calculator how much time it needs to make that distance (for example 1000m) if you are moving with ...
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149 views

Area is calculating wrong using $area in field calculator (QGIS 2.8.1-Wien)

There is a similar question posted, but the solution to it seems to be that polygons were multipart: Wrong $area from field calculator (QGIS) In my case, all polygons are singlepart. I have several ...
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78 views

Calculate area intersected areas, problem [closed]

(I'm working in QuantamGIS) I intersected two layers creating a new layer. Within the attibute table of this new intersect layer i would like to calculate the new areas. However, it just doesn't ...
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118 views

How to fill the column in attribute table with same values?

I have about 19000 records, I added new column and I would like to fill it with string values (eg. brand)- same value for all rows. I'm not considering copy/paste. I know I could do it with exporting ...
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81 views

How to assign a unique ID to groups of items in the attribute table in ArcMap?

Using arcmap's field calculator I need to programatically loop through all of the entries in the field and for each name it gets its own unique id. So names that are the same would get the same ...
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51 views

Using defined function code block with Python in ArcGIS

I am running a Field Calculation within a Python script in ArcGIS. Within this Field Calculation I am calling a defined function within a code block. Here is the dialogue that I ran and works: ...
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51 views

Concatenating fields while also replacing values within certain stings [closed]

I am trying to use python to concatenate multiple fields in a polygon layer. Specifically, I am attempting to combine the values of four fields into one: EXPCODE = !MATRIX! & !PLANT! & !PCT! ...
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176 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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114 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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66 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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55 views

How to use field calculator in QGIS to calculate new coordinates, and use that new columm to geolocate a layer's points

In a separate question, at How to shift a CRS by an observed offset, I asked about shifting a CRS to align the problems aligning data points with a satellite image obtained from OpenLayers. (They ...
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118 views

ERROR 000989 Issue with Python Script and Field Calculating distance between two long lat points

very new to scripting and I have been struggling with my script for a while. I'm not sure why it doesn't work in field calculator. I am trying to calculate a list of distance between two long lat ...
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54 views

What is the expression for getting a subset of characters in QGIS Field Calculator?

I have a column of 10 character names e.g. L3NAM1988K. How can I delete the first 5 characters and the last 1 character using an expression in the QGis Field Calculator?
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229 views

Using if else statement in Python Parser of Field Calculator in ArcGIS for Desktop?

I need help in writing the python script in the field calculator. I have three fields namely: CODE COMPLEX Map1 Map1 is an empty field that I want to populate. I have a number of conditions to cater ...
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163 views

Field Calculator - How to evaluate and sum multiple fields?

I'll do my best to describe the problem - my main issue isn't so much the python code but rather the logic I'm using. The file I'm working on is a polygon shapefile with forest attribute data. In the ...
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185 views

Remove Leading Zeros with QGIS Field Calculator

I'd like to take this attribute value: "MAP_PAR_ID": "0160011000", and populate a new field with "16-11". This works: concat(substr("MAP_PAR_ID",0,3), '-', substr("MAP_PAR_ID",5,3)) but i need to ...
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70 views

Syntax to add attributes in a line in the Expression String Builder

I have several columns with certain values, here's an example: | Apple | Banana| Orange | Pear | Expected result | 1 | 1 | 1 | 1 | red | 1 | 2 | 2 | 1 ...
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72 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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90 views

How to use Fields in the Field Calculator? [duplicate]

I'm using the Field Calculator in ArcMap and I need to create a unique ID for every storm drain in my county. An ID Should look something like this: 16-I-003 The first number is the municipal number ...
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2answers
172 views

Using the Rule-based style to calculate each grid cell from overlaps

I am using the Rule-based styling properties (QGIS 2.2) to determine the colour of grid cells for a merged shapefile. Each grid cell defined by its ID may be overlapped by several layers as defined by ...
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80 views

Arcgis 10 assign values to field based on values in other field [duplicate]

I have a table with two fields A and B, and i want fill field B with "some values" from field A: FieldA: 123456_CC; 123_D; 1234567_AB; 123456768_F I just need the "text" that is associated with the ...
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265 views

CalculateField_management - updating fields with X and Y coordinates for start and end of line

I've searched all the help documents and can't see where my script is going wrong. I've tried adding the fields as FLOAT, replacing "PYTHON_9_3" with just "PYTHON" but it just doesn't work. The ...
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92 views

Create and immediately update field using Field Calculator

You can create fields and once created, populate them with data using the Field Calculator. But can you do both at the same time using an expression? Or must you do it in 2 steps?
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31 views

Does ArcGIS Desktop have conditional function useable in field calculations?

Does ArcGIS / ArcView 10 have a conditional function, e.g. ifx(test,if_T,if_F), that could be in-lined in field calculations?
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215 views

Calculate field based on most frequently occuring text/value in other fields in attribute table (ArcGIS)

I was wondering if anyone knows if it is possible to calculate a field based on the most frequently occurring value in other fields. What I have is 5 fields with crop information over 5 consecutive ...
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756 views

How to add a new column in attribute table with attribute with indexes of another max-min ordered attribute field?

I've an attribute column named e.g. VALUE with different values I would like to make a column named e.g. ORDERsuch that the greatest value has the attribute 1 the second value 2 etc. etc. so order ...
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374 views

VBA ArcGIS 9.3 Field Calculator: 'countif' across several fields

I have an attribute table with 15 columns that contain either a '0' or a taxonomy number. I would like a summarized column that shows the number of different species. location type1 type2 type3 ...
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336 views

Cursor Update Python Script for Multiplying Several Fields against a Ratio (Real) in ArcGis

Disclaimer: Python Neophyte, Uber-reliant on GUI, working to wean... I have a Python script for replacing multiple Field values with another table value that was graciously provided by the inimitable ...
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288 views

Using a different projection to calculate areas using the Field Calculator

I have a dataset that is in a WGS84_UTM projected coordinate system, can I force the Field Calculator to use another coordinate system when I use it to calculate areas using pythons ...
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427 views

Convert a number in attribute table to binary

I would like to convert whole integers from decimal to binary in ArcGIS using the field calculator. I am looking for the equivalent of DEC2BIN excel command. All values are 255 or below so 8 bit is ...
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76 views

How to move a value from field1 to field2 using Field Calculator?

Hi I would like to move value in field1 to field2. Purpose is to after that delete the column 'field1' to get a better column naming standard /Jan
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672 views

How do you calculate a column value based on the value of another column?

I am trying to select data based on whether it starts with certain characters and then update a field. For example if [Asbuilt] starts with "WL" then do something. Here are the two methods I have ...
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2answers
4k views

Use Round in ArcMap 10.x Field Calculator on field with both numeric and NULL values

With older versions of ArcMap (9.3, 9.2, etc) I was always able to round numbers down to 2 decimal places using field calculator even if that field had both numeric values and a bunch of NULL values. ...
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1k views

ArcGIS field calculator: VBScript get data from previous row

When using the field calculator, how do I get data from the previous row in VBScript? In Python I'd do something like this: for index, row in enumerate(rows,start=1): row[index-1] += 5 I'm ...
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3k views

Replacing NULL values in geodatabase table?

How do you update NULL values within a geodatabase table using the ArcGIS Field Calculator (service pack 4) without changing other values to NULL? I've tried the suggestions on this previous ...
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Calculating a z value in python

I have some contours where the z value is stored in the geometry and I want to display it as an attribute. I want to include this in a python script. I have an expression which does this in python ...
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79 views

Autopopulating text field with string and number combination

I have an attribute table with a text field which indicates a unique identifier for each row. The identifier includes a combination of text and numbers, sequentially increasing, as follows: ...
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29 views

VB Script case statment syntax for the field calculator in ArcGIS 10.2?

Can anybody help me with this VB Script code for the field calculator in ArcGIS 10.2? Why in the final result are all the values 10? a= 10 Select Case UCase( [PRIORITY] ) Case "AUX 1": a = 22.5 ...
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54 views

If/then python for classifying existing field values to a new field

I'd like to have a tool or quick python script to classify an existing number field to a new text field. For example I have a roads layer that has a type identifier as a coded number and I would like ...