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== Extract Cross-Sections/Elevations from 2-D Domain to .csv format ==
[[QGIS_Extract_CrossSections | This user contributed tip can now be found here]]
To use QGIS to extract cross sections from your DEM:
1. Draw your cross sections using the Tuflow 1d_xs file, be sure to fill in the source column.
2. Install the QGIS plug-in "profile from line" (note you may also need to install shapely - see [http://osgeo-org.1560.n6.nabble.com/plugin-profile-from-line-td4133320.html]).
3. Run the plugin, it is pretty self explanatory, select your cross sections and dem, choose a suitable sampling interval.
4. Upon running the plugin, QGIGS will add a new points file to the workspace, save this as a .csv. This file will contain the source of every cross section as well as the corresponding chainages and elevations.
5. To split this data into individual .csv files in a format that tuflow can read in, download [[File:XSExtractor.xls]]
6. Follow the instructions in the spreadsheet, after exporting to individual worksheets use the Tuflow "Export Entire Workbook to csv" to obtain all the cross sections in a tuflow format.
Done!
== Plot grid elevation profiles==
[[QGIS_Profile_Tool | This user contributed tip can now be found here.]]
In QGiS 1.8 the grid elevation profile can be viewed using the Terrain Profile Plugin. Select one raster for which you wish to plot the elevation (you can add more later), and using the tool, draw a line. End the line with a double click, intermediate clicks will be plotted as a vertical line, a useful feature for determing locations.
An example of comparative elevations for a 10m grid and a 2m grid are shown.
[[File:QGiS Elevation Profile.jpg]]
== Alternate method for generating grid from points ==
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