Profile Tool#

The profile tool is primarily used to review the channel profile but can also be used to review table data for specific features.

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Raster Profile#

Create a Raster

  1. Set up the raster in the Profile Tool widget. In this example, the grid elevation raster is used. To create a grid elevation raster, use the Saga-Rasterize tool. On the Main QGIS Menu, click Processing>Toolbox.

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  1. Enter the search term Rasterize in the Processing Toolbox search feature. Double click the Saga Rasterize tool.

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  1. Change the dialog box as shown below and click Run. Cell size is the grid element size. Fit = cells will ensure that the raster pixels are centered on the grid elements. Saga-Rasterize is a good raster generator for FLO-2D data because it builds a raster with hidden null data. QGIS has many raster generators, and they all work slightly differently.

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The raster that is created is a temporary layer called Rasterize. This layer should be saved to a permanent layer using the QGIS Save As feature. This feature is found by right clicking the layer.

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Plot a profile of a polyline on the raster.#

The profile tool works for Levee, Channel and Street polylines that are digitized in the user layers only. This example will test it on a channel polyline.

  1. Click the Raster profile radio button and set the raster. This example uses Grid Elevation raster.

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  1. Click the FLO-2D Info Tool and click on a channel segment.

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  1. Select the segment and the elevation profile along the segment line is plotted in the FLO-2D Plot area and the Raster data along the channel line is printed to the FLO-2D Table. Any data that can be rasterized can be plotted in this manner. The table can be copied to an Excel sheet and saved.

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