 Hello, this is Hans van der Kwaas senior lecturer at IOT Delft Institute for Water Education. In this video, I'm going to show you again how to calculate the longitudinal river profile, but now based only on the native algorithm, so without using plugins except the data plotly plugin. So make sure you have a DEM and a river line factor. We're going to use the points along geometry tool from the processing toolbox. And then we can set the distance, 2000 meters for example. And then we save it to a file, I call it river sample 1000, then we run it. And now I want to sample the DEM at those 1000 meter sample points. So I use sample raster values, choose the DEM, then I give a prefix of the field in the attribute table and now put file name, river sample the 1000 DEM. And there we see the attribute table and we see the distance and the DEM columns and that's what we need. So now we can use the data plotly plugin. I use a bar plot, choose the right layer, choose distance and the DEM values, change the legend title to 1000 meter sample points, put a nice X label and a Y label and then create the plot. There it is. We can improve the plot a little bit more. So I would like to have the distance and kilometers, otherwise the numbers are a bit large. So divide it by 1000 using the expression dialog. Then I modify here the label to distance and kilometers, change the title to one kilometer sample points, change the plot title to longitudinal river profile, then clean the plot canvas and create a plot and there we have our graph. You can also include these graphs in the print layout. There's a new tool there where you can insert these data plotly graphs if you want to include it in your style maps. If you like these videos, subscribe to my YouTube channel and you'll get updates and for more free materials go to ishiedel's open courseware at gisopencourseware.org.