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== How to Update a Column (Equivalent of MapInfo Update Column) ==
[[QGIS_Update_Column_Values | This user contributed tip can now be found here.]]
To quickly enter the "f" (multiplication factor applied to the boundary values) attribute for all CN type boundaries
1. Open Attribute Table
2. Select all CN attributes, this can be achieved if you sort by type so that all CN attributes are grouped,alternatively, for more complex situations, use the Advanced Search tool in the bottom right. This allows you to select using an SQL Query
3. From the attribute table, open the field calculator (you need to be editing to open the field calculator)
4. Ensure that "Only update selected features" is turned on, and set the "Update existing field" to "f"
5. Type "1" into the "Field calculator expression" box and hit "OK". Note, if you want to insert a string such as 'S' you need to enter it with the inverted comma.
[[File:FieldCalculator.jpg]]
Done!
You can also use the field calculator for more advanced tasks, for example when naming the Source attribute for XS, the expression
'XSName'||rownum*50-50||'.csv' **NOTE** Do not copy and paste the expression to the left into QGiS - it has to be typed within the QGIS interfac. Do not type the "||" character either, at the time of writing this operator has to be selected from the available operators in the field calculator.
will generate in the source column:
XSName0.csv
XSName50.csv ...etc
== Extract Cross-Sections/Elevations from 2-D Domain to .csv format ==
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