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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Calculating values of field based on two others using Field Calculator in ArcGIS Desktop?

I need to combine two fields in an attribute table. I want to do this using the field calculator. What is the proper script to write to combine a field called "name" and "type", so that it produces ...
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292 views

Debugging error 000539 from ArcGIS 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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32 views

Iterating through list of fields using field calculator?

import arcpy, sys, itertools arcpy.env.workspace = r'path to geodatabase' fields1 = ['gearqty', 'cnemarea', 'fzone', 'qdsq', 'tensmsq', 'crew', 'nanglers', 'port', 'totalquant', 'trip_days', ...
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90 views

Update multiple fields/columns in QGIS

I need to update fields in attribute table of a vector using QGIS. I use field calculator for each field, but i have too many fields (and too many vectors also) and i need to program the task. The ...
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74 views

Populating attribute table string field with values from long field using vbScript in ArcGIS Field Calculator?

I want to calculate the field "area_type" with text depending on numbers from the "Value" field. I have tried with the following VB-script in "Field Calculator" but am getting this error message: ...
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84 views

Replicating Summary Statistics tool with case field using own calculation within ModelBuilder?

I thought this would be a simple problem to solve, by my googling hasn't provided the answers so far. I have created a near table (Using the 'Generate Near Table' in Arc) comparing two sets of ...
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40 views

How do I round the coordinates of a point before insert into attribute table in ArcGIS?

Until now I doing the following steps to get rounded coordinates: create a new x and y column in the attribute table use Calculate Geometry round the column value with the Field Calculator using VBS ...
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77 views

How to copy same values to another field in attribute table in QGIS using field calculator?

I am trying to copy values from Parsel_ID to Parsel_NO using an equation ( look at pictures) in field calculator but it is not working. What is the problem and how can I success this task??enter image ...
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41 views

Calculating field on insert (real time) using QGIS?

We use QGIS as a field application. We like to calculate with a input value and then also calculate with the result of the calculation Example: Liters: 1000 -> Liter per container: "this has to be ...
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112 views

using field calculator on string field that has some empty values?

I have a CityState field that has the city and states of landowners. Bellingham WA, for example. I am making two new fields, OwnerCity and OwnerState in which I strip the last two characters of ...
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132 views

How to calculate azimuth in QGIS field calculator?

Is there any way to calculate the azimuth of two points in the QGIS field calculator? The coordinates are stored in an attribute table. x1 | y1 | x2 | y2
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79 views

Conditional Statements in Arc Map 10 (field Calculator)

I'm attempting to calculate the values of a field based on IF THEN statements in ArcMap 10 (in field calculator) but I haven't succeeded yet on that. What I want to add is the following expression: ...
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70 views

CalculateField with variables

I'm trying to make a python script on arcmap 10.2.2 which will copy values from an old field (selected by the user) and paste them in an new field (named by the user). I wrote that: fc = ...
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144 views

Create new attribute ranking polygons by size in QGIS

I'd like to create a new field in the attribute table which gives the rank of the polygon by size. For example, the polygon of the largest size would be rank 1 and the smallest rank N. I was hoping ...
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90 views

Add and Calculate Field in Table with ArcPy?

I have written the following script to iterate it as a tool for all my tables with ModelBuilder, but i have a problem wth my codeblock. I want to add a field FID to all my tables and to add the values ...
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82 views

How to update a bulk selection of fields using field calculator in QGIS 2.8.1

I have an attribute table showing vegetation communities. The table has three columns ("ID", "Veg Comm" and "Area_ha". Instead of having to copy and paste text after each polygon created into each ...
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69 views

If statement problem in Field Calculator - Arcgis

I have a field entitled "Lung_lunc". It contains some "0" values and the rest are values > 0. I want to turn those "0" values, into "0.0001". I have added a new field: "Lung_lunca", and I want to use ...
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93 views

ArcGIS Field Calculator nested elif is None not working

I am calculating a field based on two other fields in ArcMap 10.2 using python. My Pre-Logic Script Code is def myfunc(legend,Btype): if(legend == 'Apple'): return 'Banana' elif(legend == ...
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186 views

How can I allocate a $rownum in reverse order in QGIS?

How can I allocate the $rownum value in reverse order in QGIS? I have a created a grid layer to use in an atlas and the ID allocated is from top left to bottom right - which is what I want if I want ...
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177 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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96 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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124 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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48 views

how multiply a ranges of values for other value on python

I need multiply ranges>1.5 and <=4.5 * 9, but I am new in this type of language. please help me. def CalcD(Level_water) if Level>1.5 and <=4,5 * 9
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425 views

What's wrong with this VB Script code for the field calculator in ArcGIS 10?

I am trying to use one field's contents ([Condition]) as a condition for populating another field ([Intact]). I try to run the following code in the Field Calculator, but it never works (and is not ...
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289 views

Calculate value from an equation using Field Calculator Python/VB Script

I wanted to calculate a result value from 3 fields using an equation. VBScript or Python codes are also accepted..:-) the equation is RESULT= [(R^2/3)(S^1/2)]/n..
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637 views

Slow performance with Add Join and Calculate Field?

I have a point layer and a table with approximately 100 fields. I need to join the table to the point layer based on a key field and create a new shapefile / feature class. This script has been ...
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128 views

Calculating Field B from Field A, except where Field B has existing value, using ArcGIS Desktop 9.3?

Im trying to calculate Field B from Field A except where Field B has existing value in ArcGIS Desktop 9.3. (I suspect its straight forward but I have 'searched' and havent cracked it yet) Any ...
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388 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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172 views

How to include a quotation mark in a text field from field calculator

I'm trying to attribute pipe size and need to include a quotation mark in a text field. How do I include that in the field calculator. "4"" doesn't work.
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105 views

Python in ArcGIS, CalculateField_management, updating with single value

I have a float field which I want to simply update all values with 1. I can easily do this within the field calculator but I have started using python today, what is the syntax to simply update a ...
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290 views

Iterate through each county in a shapefile, select the county and make a second selection by location - modelbuilder

The goal of my project is to create a table with two fields. The first field showing a county name and the second field listing every county that touches the boarder of the county listed in the first ...
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156 views

Use field calculator in QGIS so get number of points in polygone and store it in attribute table

I have to layers, one point one polygon (with 6 areas) stored as shapefiles. Now I want to count the number of points in each area and write it into the attribute table of the polygons. A column ...
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2k views

How to fill attribute field of one feature based on calculation on attribute field of another feature

I would like to fill an Attribute field of a geodateabase table based on some calculations such as 'sum' over specific field of another Feature class. Is there an Approach to formulate it? while in ...
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460 views

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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393 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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468 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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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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497 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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348 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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33 views

Using Calculate Field to fix hyperlinks in ArcPy gives Cannot use VB for services?

Getting an error while trying to script it, specifically "Cannot use VB for services." Snippet and VB code block as follows: Raw block (works within ArcMap): "\ftp\raw\YYYYMMDD\Files\Charles" ...
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38 views

How to edit virtual field definitions in QGIS?

I have a virtual field in QGIS. The values are updates depending another column with a concatenate CASE statements. I would like to edit this statement but I cannot see it. I have attempted to use ...
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3answers
50 views

Using Field Calculator to compare two fields in att table and returning if equal or not in ArcGIS for Desktop?

Using 10.2.2 I am attempting to compare two fields in an attribute table using the Field Calculator. I'd like to return a value of '0' if they are equal and a value of '1' if they are not equal. ...
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34 views

QGIS field-calculator: set attributes to 1 if country name is in a list of values

In a country table, I create a region field, ECOWAS, with 1 if the country belongs to the regions 'ECOWAS', 0 else. Country names are in the field "sovereignt". How can I build a field-calculator ...
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105 views

Python script for if/elif condition in field calculator [duplicate]

I need some help in calculating the last column (OD_pairs.Ai_) based on the condition; if travel_cost has a value below 10, OD-pairs.Ai_ takes the value of the first column(Aij_OjFCij..) if ...
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54 views

Using python to do a interpolation on field calculator [duplicate]

I need to increment a row in attribute table: def func (w,v,pot): return pot + ((pot+1 - pot)/(v+1 - v))*(w-v) The "+1" is not the addition of number one to the variable, is the intention to ...
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70 views

Removing extra string from text column in Attribute Table to make numeric column from number part using ArcGIS Field Calculator?

I received a shapefile about invasive species. I am using ArcGIS 10.2 for desktop. In Attribute Table, there is column called "Infested_Area" and its got number mix with text, for instance "9100 sq ...
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139 views

Passing two variables into codeblock of Calculate Field tool of ArcGIS Desktop?

I have a script tool that truncates each word in field to 3 characters and outputs the result in a new field: "THIS IS AN EXAMPLE STRING" becomes "THI IS AN EXA STR" import arcpy ...
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31 views

Field Calculator Mass Change Freezing issue, Any other options?

I have a list of ~2300 points, that i need to change a whole field's ("JointUse") attributes from null to "N" (for No). I've tried doing the basic field calculator change but I'm assuming since I'm ...
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46 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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56 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 ...