Introduction to PyQGIS

6. Conclusions

In this tutorial you've learned to:

calculate the volume below a specific elevation in a DTM
use QGIS Processing Tools with PyQGIS in QGIS
use PyQGIS in Python without the QGIS user interface
create a Stage Volume Curve using PyQGIS and Pandas

There's much more that you can do with PyQGIS besides this example to introduce you to PyQGIS.

A good starting point is Anita Graser's PyQGIS 101: Introduction to QGIS Python programming for non-programmers.

Also the tutorials by Ujaval Gandhi are a very useful resource.