I have a line feature class that needs to have its slope included as a field. I have a point layer that contains points and their elevations for the start and end of the line segments. How can I calculate the slope of the line feature class using my point layer? I am open to Python, QGIS, & ArcMap solutions.
Join the points to the lines, using a spatial or table join, to give the elevation (Z) at each end of the line. This allows you to calculate the elevation change (Z1 - Z2). Use your GIS to calculate the 2D length of the line (Shape.length).
This allows you to use SOHCAHTOA to calculate the slope angle.
tan(slope) = (opposite / adjacent) slope = atan(opposite / adjacent)