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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Capitalizing The First Letter Of Each Word In Attribute Field QGIS

I have tried capitalizing the first letter of each string in my field/column called "COMMUNITY" by referencing this post: Capitalizing The First Letter Of Each Word In Attribute Field Particularly: ...
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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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85 views

Reproducing GRASS GIS network analysis tutorial in QGIS Field Calculator

Im looking to reproduce the assigning of road speeds as denoted in a GRASS GIS tutorial (v.net.alloc tutorial), where the road speed is assigned by road type (i.e. 'interstate' = 75 mph etc.) to then ...
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Arcmap field calculator python script returns no data

I am running ArcMap 10.2 I have 4 fields with which I am working. many have duplicate entries. in order to find the single correct entry from all the duplicates I am trying to calculate out the ...
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167 views

QGIS 2.12 attribute table update question

I'm trying to fill in a whole lot of cells in the same column of an attribute table all at once using the field calculator. Am I on the right track with the following expression? "Author" || example ...
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697 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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233 views

Using IF operator with Python parser of ArcGIS Field Calculator?

I want to assign numbers to a certain types of building and I need to use field calculator. I tried many different versions of this and I still cant find whats wrong. Could you tell me where do I ...
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257 views

Use Get Field Value tool to calculate field?

I am running a summary statistic on a clip to get acre counts by area type. I want to then add a second field that has the acre count from the total area. A third field be added so that it shows as ...
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60 views

Using timestamp field to auto complete source field in QGIS

I am trying to use my timestamp field to autocomplete my source field in QGIS using the field calculator. I want my source field to be completed with a saved string e.g "Sam_Sam". I want my source ...
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158 views

Filling fields with conditional clauses

I have four fields in my shapefile. I would like to fill only one of them (cell of attribute table) and automatically after to write one cell the others one will be filled by conditional clause. I ...
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83 views

Python if/then Statement in Field Calculator to return 0 or 1 based on numbers divisible by 28?

I don't use python all the time. In a point feature class, I'm trying to populate an ID field with 1's and 0's based on whether the FID is divisible by 28. I've started the following code but can'...
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95 views

Understanding if-else statements in ArcGIS field calculator when coded value domain used?

I am attempting to set a newly created field based on the strings in another field 'TNMFRC'. I am pretty sure that I have the code write, and yet everything is set to a value of '6'. Here's my code: ...
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202 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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Help with else/if else in arcMap? [closed]

I'm attempting to create quick code that simply assigns a gps coordinate to a certain station on the map. Here's my current code Pre-logic script code: def update_nones(lat,bay_statio): if bay_statio=...
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67 views

Getting different values for area field calculations using ArcGIS Desktop?

We have self developed application based on ArcGIS 9.3.1 SP2. Our agents use that application to edit parcels. The parcel layer has a field SHAPE_AREA that is calculated by ArcGIS. Our application ...
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122 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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40 views

ArcGIS 10.2: VB to Python

I have the following VB code to produce a percentage in a field calculator. " [FIELD_1] / [Total]*100 " It works in VB. I've tried the following without luck. !FIELD_1! / !Total! * 100 Can anyone ...
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224 views

Unable to replace Null values using Python parser of ArcGIS 10.0 Field Calculator?

I'm using the following python code to replace Null values by 0, using field calculator: def nulls(p1): if p1 is None: return 0 else: return p1 But nothing happens, Null values stay. I'm ...
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ArcGIS 10.0 Python script won't recognize null [duplicate]

Has anybody ran into in issue where Python field calculations and/or scripts won't properly query Null (None) values? The calculation I'm working on is a little more complex, but even the simple ...
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49 views

Using Arcmap to update a field based on data from another fields

I'm trying to update latitude and longitude data per individual station for a lab I'm working for. Here's some code I have that's supposed to assign any all bay stations of a certain name the ...
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58 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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40 views

A script to populate a numeric field in Arcgis based on some content of a string field?

I have field in an attribute table populated with expressions like "6S2Olch1E", "10S1B", "9B3S2Olch" and so on. I need to make a numeric filed populated with only numbers associeted with letter S from ...
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57 views

Calculate field using data from excel table

I need to interpolate data that I have in a excel file using data from an attribute table of a point feature. I want to create a new field on the attribute table with the result of that interpolation. ...
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263 views

Writing expression syntax for Calculate Field in ArcPy?

I'm stuck on my CalculateField function with how to correctly type the syntax. I'm not particularly tied to the variables I assigned up front. The issue is syntax for the expression. I am ...
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134 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

Calculating percentage using QGIS Field Calculator?

I have a shapefile containing counties and their respective population for a given area. I woould like to use the Field Calculator to create a new field that contained the % of the total population in ...
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Calculating Grid square page names using loops, counters/cursors [duplicate]

I've created a large grid of 1 sq-mile cells to use for QC projects at my job. I've given each row a letter ID, and each column a number ID. So the grid starts with A01, goes to A02, etc. Next row ...
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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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359 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 arcpy.env....
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136 views

Create list of [X, Y] coordinates within field calculator

Lately i've been working on a script that must calculate a value in ArcGIS field calculator based on all vertex coordinates of a polyline. But i am struggling to create a list of a polylines ...
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66 views

calculate specific rows and populate their result in another field

I'm working on ArcGIS 10 desktop version. I have a file with one entity entered multiple times (rows) and each time that has been given a new value against it. I want to sum the values against this ...
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37 views

Updating Values in FIelds of ArcGIS editing only portion?

I have total 96 records which are having duplicate values like 999999. What i want is to convert these values into unique ones like 999901,999902,999903 and so on, through the 96 records. I want ...
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137 views

Convert Field Expression to ArcGIS Python Script Tool

I've created the following field calculation that I'd like to convert to a python script tool: def blocklow(a, b, c, d): mylist = [a, b, c, d] # create list from input range variables if mylist =...
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85 views

Selecting numbers within the slash (/) using ArcMap Field Calculator?

I have date data that I'm separating into three separate fields (all fields are string type, including the input field) by day, month, and year. Unfortunately, the date field is raw data and isn't ...
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166 views

Find minimum in a column of attribute table using python on Field Calculator

I have a column X in attribute table where the values are repeated in some lines. What I need is to make a condition that says: when the values in column X are the same, find the minimum of column Y ...
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81 views

Extracting a Feature Class' Name, and Adding It to a Field

I'm building a bike network dataset based on an existing street network. Each bike lane/route/path has a unique ID number (assigned by our engineering deparment) that must be included in a separate ID ...
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65 views

How to assign a new name for values selected from two columns?

I'd like to assign a new name (either HIGH, MEDIUM or LOW) to values selected from different columns in ArcMap 10.3 I selected the two values from the two columns ("MAIN_ROCK" and "SUB_ROCKS") using ...
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How to select different values from two columns through Select By Attributes?

I'm using ArcMap 10.3. I'm trying to select by attributes different values from two columns. I want to define the areas where Main rock is GRAVEL And Sub-rocks are : a. mudstone tephra loess b- ...
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68 views

How to create a sequential unique id by groups?

I'd like to use the field calculator in QGIS to create a unique feature (polygon) id that reflects different levels in a geographic hierarchy. So say I have a REGION attribute within which there are ...
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49 views

Calculate proportions of point counts per polygon based on threshold values

I have an attribute table containing "Joint_Count" and Raster ID (A1, A2, etc), where Join_Count refers to the sum of points per raster ID. If the sum of all Join_Count represents 100%, how do I ...
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Using ArcGIS field calculator to rank continuous field within shapefile using VBscript parser? [duplicate]

So have been trying to get the VBscript code below to work in the ArcGIS field calculator. The values are a continuous set of data between 15-88, and I have used the natural breaks jenks rank to rank ...
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99 views

Syntax error in parameter formula of field calculator funtion

I'm using a QGIS 2.8.1 in windows. Have some doubts with syntax when use string in python console. I want to use the field calculator funtion like: processing.runalg('qgis:fieldcalculator', input, ...
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189 views

Calculate QUARTER from Date field using ArcGIS Field Calculator?

I currently have a Date field in the format of MM/DD/YYYY. My goal here is to convert the Dates into 1 of 4 quarters, along with the Year. The field to be created will be called QTR_YR. My first ...
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45 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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123 views

Calculating XY in Model Builder using Calculate field

I'm trying to calculate the lat/long of a feature class in GCS NAD83. The picture shows what goes below. I can get it to work for distances and areas, but not a centroid. What looks incorrect?
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Way to find minimum value from a group of values - QGIS?

I'm wondering if there is a way to find the minimum value of a group within QGIS? Basically I need to find the minimum distance of each unique value in a table of about 5000 records. I can do the ...
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Debugging Indentation error on Python Parser of ArcGIS Field Calculator?

Would anyone please help me find out why I get an indentation error in line 3 def calc(f1,f2,f3): remove_list = ['01ST', '02ND', '03RD', '04TH', '05TH', '06TH', '07TH', '08TH', '09TH'] if f2 in ...
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1answer
68 views

Python codeblock to remove numeric characters from a column not working

I am trying to make use of a codeblock found in this thread: How to remove numeric characters from alphanumeric value in field calculation? I put this code into the pre-logic script field of the ...
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944 views

If/else statement in arcgis

I try to fill the fields with the condition if / else but it does not work. I do not know where is my mistake in the code. def TextValue ( !Classe! ): if !Classe! == "Steppe arbustive" or !Classe! ...
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2answers
94 views

type mismatch: 'esri_8' when using field calculator

I am trying to run the VBScript 'round' function using the field calculator on a column for a numeric field that contains a large number of rows (> 500k). When I run the code on a subset of the field ...