Field calculators (which are available in QGIS, ArcGIS-related products, etc.) can recalculate the values of a single field, on all, or selected records within a table based on a symbolic expression.

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Force the decimals to use the comma in Field Calcuator ArcGIS 9.3.1

Can I add the comma "," to force the decimals to remove from the attribue and replace with the number? For example, I have an Acres field column that says 506320.0750 and I want to replace the decimal ...
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2answers
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VBA functions use in ArcGIS Field Calculator

Would this be ok to use them for the field calculator in ArcGIS 9.3 ? See here MS Excel VBA Functions Or should I fix them in MS Excel and save as a file and then use the join with the shapefile or ...
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1answer
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How do I add a hyphen to the Field Calculator to merge 2 columns?

I am trying to build a field calculator expression to merge two columns into one. I am looking for the word that makes it a range. Example: I have 2 columns in elevation, From and To. I want to ...
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5answers
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Is there a Log or Ln function in QGIS Field Calculator?

I can't seem to find any way to take the logarithm (natural or base 10) of a field in QGIS. I have gotten to the field calculator but there is not a button for log and I can't seem find any formula ...
2
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1answer
360 views

Why does this python function return a value of 0 in field calculator?

I am trying to calculate the percentage of a total which the median value makes. I have a column with the median column labelled (i.e. 1st,2nd,3rd,4th column is median), the columns of values and the ...
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1answer
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Qualifying field names in field calculator

I am trying to set up a quick model that: Takes a point feature layer of development projets (a table in an access database with xy coordinates), Spatially joins polygon neighborhood designations to ...
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4answers
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How do you test for a NULL string field in the Field Calculator with Python?

I am trying to perform an operation on a string field with a condition that it contains data. Referencing None with Python does not appear to work when the field is nullable and contains <Null> ...
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5answers
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How can one execute an SQL script in field calculator in ArcGIS 10?

I am trying to transfer over row data from a table to columns in a shapefile table. There is a common "SA" variable between the two (i.e. the study area number) but there is more than one land use ...
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2answers
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How to calculate perimeter of polygons in Quantum GIS?

Is there a way to calculate perimeter of polygons with the field calculator of qgis, like there is for area calculation?
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1answer
342 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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3answers
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ArcGIS 10/arcpy: Help needed with syntax for CalculateField_management in Python script

I need to use CalculateField_management in a Python script, and the calc expression needs to concatenate a runtime variable, a string, and a field (string) value. I have searched all over for ...
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Arc 10 field calculator scripts

I need scripts for the field calculator that: extracts the first word from a column, i.e. "Jones School" - "Jones", and A script that will capitalize this new field, "Jones" - "JONES". This is Arc ...
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4answers
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Is there a way to concatenate fields in field calculator of QGIS?

Is there a way to concatenate fields in field calculator of QGIS? (e.g. hectares + ' ha')
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1answer
883 views

Editing tables using SQL in ArcMap

We've recently started working with ArcMap, having used MapInfo previously. I've created a shapefile in ArcCatalog and want to update some columns using SQL. In MapInfo I'd write the following command ...
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3answers
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python: Replace Variable in VB-Expression-File (.cal) [ArcGis 9.3]

I'm trying to modify a VB-Expression saved in a cal-file: dim out if [D19830701]=-9999 then out= [D19830501] else out= [D19830701] end if __esri_field_calculator_splitter__ out with this ...
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2answers
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Using Field Calculator in QGIS to update columns with centroid coordinates

In QGIS I would like to update two columns with the centroid easting and northing of my polygons. I am using the field calculator. I have tried using $x and $y but this only seems to work for points. ...
2
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3answers
797 views

Field calculator script not working

I am trying to do the following in the field calculator in ArcGIS 10 if [IncdStDir] = " " then [IncdStNo] &" " & [IncdStName] &" " & [IncdStSfx] else [IncdStNo] &" " & ...
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1answer
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How to populate a field with the max M value of a feature using Python in Field Calculator?

I need to calculate the max M value for a line feature using Python in ArcGIS 10 Field Calculator but I cannot figure it out. In 9.3 I used the follow VBA expression… **Pre-Logic VBA Script Code:** ...
6
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1answer
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ArcMap Field Calculator syntax (again)

I'm trying to string together a field calculator script that will populate all the records of a field at once based upon values in a number of fields. I can't even get the first part of the command ...
5
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1answer
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Python Field Calculator ArcGIS 10 expression for a RANGE

what is the python expression for defining a range of numbers? I have tried numerous combinations but cannot get a simple range of angles (100 -200) to compute correctly. Screen shot : screen shot ...
4
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1answer
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Find and Replace expression needed in Field Calculator ArcGIS 10

Looking for the Field Calculator code (Python preferred) to replace the last numeral values in a field using another field's values for entire attribute table. Please see screen shot here:
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1answer
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How to set the value of a field in all selected rows of a table using ArcGIS 10

I have an attribute table in ArcGIS (it's large - around 300,000 elements). I've selected some rows of the table using 'Select by attributes' and I want to set the value of a field for all of those ...
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2answers
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Basic Field Calculator Python Question

I'm trying to used the Python syntax in ArcGIS 10's field calculator and am thoroughly confused. So far the most basic calculations are failing me, and I don't understand why. I'm trying to create a ...
4
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2answers
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If/then VBScript/Python code equivalent to SQL IN ('x','y',z') expression in ArcGIS Field Calculator?

we need just like the following, only with multiple records selected... have tried the "xyz" in (1,2,3,4,5) SQL code but of course VB Script wants something else. dim f2 if [field1] = "foo" then f2 ...
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0answers
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How to set order of operations for Field Calculation in Network Analyst Evaluator Dialogue? [closed]

I desire to have a ratio calculated each time I create a new route. To get this ratio, I created and populated a field that multiplied the length of each segment by a designated number from 1-5, ...