The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory currently holds the Guinness World Record as the world most powerful pulsed spallation neutron source. Neutrons scattered off atomic nuclei in samples yield important information about the position, motions, and magnetic properties of atoms in materials.

A typical neutron scattering experiment usually involves sample environment control (temperature, pressure, etc.), mechanical alignment magnetic field controllers, and neutron velocity selection and detectors. The SNS Data Acquisition System (DAS) consists of real time subsystem (detector read-out using custom electronics), data preprocessing and a cluster of control and ancillary PCs that communicate with each other via TCP/IP.

PyDas is a set of Python modules that are used to integrate various components of the SNS DAS system. It enables customized automation of neutron scattering experiments in a rapid and flexible manner. It provides IPython command line interface as well as graphical user interface using wxPython. Matplotlib and NumPy are used for data presentation and simple analysis.

We will present an overview of PyDas architecture and implementation along with the examples of use. We will also discuss plans for future development as well as the challenges that have to be met while maintaining PyDas for 20+ different scientific instruments.