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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Using UNC pathname with Calculate Field tool in ArcPy?

This question is different to Using Calculate Field to fix hyperlinks in ArcPy gives Cannot use VB for services? which was asked previously because it is using the Python parser specifically, rather ...
0
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1answer
29 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" ...
3
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2answers
90 views

Field calculator if and elseif statement with <Null> values in ArcGis 10.1

Trying to figure out how to get this "Headwater" column to indicate "Yes" (or 1) if the value of "NextDown_Copy" is "" and "No" (or 0) if it has any other value (eg. 7100381010). I attempted to ...
1
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1answer
53 views

Virtual fields are lost when duplicate layers

I've just upgraded to QGIS 2.12.3 - and hoped that the issue which was really time-consuming in 2.12. <3 could have been solved ... On duplicating layer - with tons of joined tables and virtual ...
6
votes
4answers
246 views

Need to find strings that contain the same word twice

I have attribute data with owner names. I need to select data that contains the last name twice. For example, I may have an owner name that reads "BENNETT MCCARL & ARNETTE BENNETT". I would like ...
24
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2answers
45k views

How to calculate polygon areas in QGIS?

Hi I would like to simply calculate areas of a area-shape file in square meters or in acres (ha). I didn't find that functionality in the vector tools. Could anyone here help me with that?
2
votes
2answers
50 views

Field Calculator - conditional function and string variable?

I know this question has been asked before in different fashions, but I can't seem to get my python script to work despite looking at all the relevant questions I could find. I am simply trying to ...
0
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1answer
50 views

QGIS loop/iterator with python in function editor (field calculator)

I am trying to create a loop to rename the fields of my attribute table. The fields should start at 1 and increment by one until the end of the table (e.g. 1,2,3,4,5,...,n) my code on the python ...
2
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0answers
34 views

Finding and using mean and standard deviation value in field calculator

I am creating a field for a z-score of a particular attribute. This requires calculating the mean and the standard deviation for the attribute across all features. I've been using the statistics ...
3
votes
1answer
31 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 ...
1
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2answers
69 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, ...
2
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1answer
364 views

Finding distance between consecutive points using ArcGIS Desktop?

I am wondering how I can get the distance between consecutive GPS locations in ArcMap 10 (i.e. the distance between consecutive GPS locations sent in during a wildlife telemetry study).
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10 views

Finding distance between consecutive points using ArcMap Field Calculator? [duplicate]

I am very new to ArcGIS but I am working on a data set consisting of GPS locations of radio tracked freshwater turtles. I am trying to find the distances between the points in order. Can someone ...
0
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0answers
19 views

Replacing multiple fields with Python [closed]

I have just started to learn how to use Python for ArcMap and am having some trouble with a task I have to do. The question is like so: Create a Field Calculation that will create a text value ...
3
votes
1answer
67 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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1answer
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', ...
0
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2answers
41 views

Calculating percentages in ArcGIS field calculator gives TypeError: 'float' object is not iterable?

I am trying to calculate the percent AREA in each class. I have created a new percentage field and have tried to populate it using the following equation in python in the calculate field tool. ...
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0answers
32 views

Converting Atn function of VB Script for Python parser of ArcGIS Field Calculator? [closed]

I would like to convert the Atn function (which returns the arctangent of a number) of VB Script to Python but I cannot find exactly the same function. Any help? I want to convert the slope of ...
3
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2answers
46 views

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 ...
2
votes
4answers
74 views

Calculate Length Totals in ArcGIS based on field values

I am having trouble finding the right words to describe this problem but here goes: I have 3 values (120,270,380) in my field called operatingvolt for every segment of conductor. Each segment of ...
1
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2answers
79 views

Calculate field more wisely

I first classified firstCol into groups and then I want to give the groups with different weighted values in another field, SecondCol. I will need to give different weighted values very often. I find ...
10
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2answers
1k views

Computing new attribute based on changes in another attribute using ArcGIS Desktop with Python?

I am attempting to classify a set of gps time-encoded point data into behaviors based on different attributes. I have created an attribute that is 0 for home and 1 for away based on location, and ...
15
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6answers
6k views

Find/Replace Double Quotes using Python Parser of ArcGIS Field Calculator?

I'm trying to use the Field Calculator (ArcMap 10.0) to strip out double quotes in an address field (I didn't put them in there, believe me). I've tried many incantations but am still unable to even ...
7
votes
1answer
8k views

Adding automated values to attribute field?

I have parcel and buildings layers. In their attribute tables I want to replace "NULL" values with numbers from 1 to 2000, in "Parcel ID", or "Building ID" field. How can I do this in ArcGIS ...
0
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1answer
559 views

Adding sequence numbering based on attributes in table? [duplicate]

Is there a way to auto populate a sequence of numbers based on another attribute in a table? For example, if field "Name" has a sequence of numbers from 1 to 10, and I want to number all the rows in ...
1
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1answer
20 views

Calculating average values of condition or receive values from a table for calculation in another table

I have a table with data (in this example the field "TSS"), a field time corresponds to the data for each point. I want to create a field with the mean values for each point all time values, without ...
1
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1answer
4k views

Concatenating fields using VBscript in ArcGIS Field Calculator?

I'm trying to get one column of text to move into another column that already has text. I DON'T want to replace it, I want the transferring text to be added to the already existing text in a shp file ...
2
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3answers
88 views

If else if in ArcMap Field Calculator (Python)

Help! I think I am missing something that must be so obvious but I cannot figure out what I am doing wrong. Here's some background: I have one short integer field (MajAspNum) that has values ...
2
votes
4answers
89 views

IF else statements arcmap, using python

I have a shapefile with a number of fields. I have one field (let's call it Field A) that I need to populate based on another field (let's call it Field B). If Field B is greater then 0 I need it ...
0
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0answers
22 views

Calculate field for each Feature Class in Dataset using Python and different arguments

I have Dataset with Feature Classes in it. I'm building this in ModelBuilder. I want to calculate new field (SMB_ID) depending on attributes for each feature class. I was trying to make it simple ...
2
votes
1answer
59 views

QGIS processing toolbox: fieldcalculator - update only selected features is not possible

I am working on a model where I need some calculations on only some selected features. In the normal fieldcalculator you can check 'only update ... selected features'. When using the fieldcalculator ...
3
votes
1answer
30 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 ...
2
votes
1answer
79 views

Running ArcGIS field calculation using Python with algebraic expression using other field values as variables?

I'm trying to run a field calculation using multiple fields in a table as well as independent numeric values with python code in the field calculator window. I've included the first 7 lines of the ...
2
votes
1answer
37 views

Rename cells in Attribute Table to 'XXX.$ID'

I feel like this should be easy to answer, but I can't get it to work for me. I need to edit the attribute table of a .gpx file before I load it into my GPS, in order to label the points. I can rename ...
1
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2answers
34 views

How to compute the distance from the current polygon centroid to another in QGIS field calculator?

There is layer with polygons. I want to save in new field distance of every polygon's centroid to centroid of one particular polygon. To do this I should write some expression like this: ...
2
votes
2answers
55 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 ...
3
votes
3answers
69 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 ...
3
votes
1answer
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 ...
1
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1answer
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 ...
1
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1answer
461 views

Join and Calculate vb.net

Im trying to join an excel table to a shapefile and then calculating those fields using vb.net. The code I have written has no errors, but won't work when I try it in ArcGIS 10.1 and I'm out of ideas. ...
2
votes
1answer
78 views

Using ArcMap Field Calculator to count number of identical values?

I have a file with an attribute table with data in 3 columns, and would like to use field calculator to populate a 4th column. The data is integer numbers between 0 and 56. I want the new column to ...
1
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1answer
20 views

Polygon Surface Area Calculator in different map projection(s)

I'm simply looking for an online tool or a utility to calculate the surface area of the same polygon (i.e shapefile) in different projection (projected and geographic projection system) systems. It ...
-3
votes
1answer
38 views

Calculating field gives invalid expression in QGIS?

I am a new user of QGIS and I want to add a new field in my attribute table named densite which can be calculated by POP(population) / Area, in Field Calculator, I wrote POP/Area no result !! invalid ...
4
votes
2answers
598 views

Calculate average value for each row

The picture is an example, but the method would be the same at mine bigger dataset. So i have some parcels with each a ID value and some fields. such as field 1, field 2, field 3, fieldd 4,... with ...
2
votes
3answers
46 views

Add value to entire column in attributes

Is there a way to add a value to the entire column? I don't think i can use raster calculator because it's a text i want to add, the letter "B". Here is a picture. This is what happends when i use ...
4
votes
3answers
3k views

How to count occurrences of one field grouped by values of another?

Is there a way of calculating the number of unique text strings in a field in ArcGIS 10.1? I have a number of repeated strings in this field, but would like to calculate the number of unique strings ...
2
votes
2answers
30 views

Using Field Calculator vb to check for name with /n in the string?

I am calculating values for a field (Score) based upon the names from another field (Modified). One name is "blaugh\nblaugh". Field Calculator keeps treating the name as having a new line command. I ...
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votes
1answer
21 views

calculating sq ft of an picture image with only a scale bar as reference

I have an architectural image of a building. However, I had to change the blueprint and extend the walls out further increasing the total sq.ft., and simply for the means of drawing out the new ...
1
vote
1answer
313 views

How to create sequential field based on sorted data? (or extract pop-up data?)

I downloaded a kmz field and converted it to a GDB fc on arcmap. However, the field I need to label the layer by is stored in the pop-up html field... It looks like this: <html ...
1
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0answers
33 views

Calculate z score into new field in ModelBuilder?

I'm trying to calculate z scores for a given column. I am working with a shapefile, that contains fields like percent poverty, percent tree canopy and temperature. My ultimate goal is to add new ...