FluidSF: A Python package for calculating turbulent flow statistics

Fluid systems are everywhere, from small-scale engineering problems to planetary-and largerscale systems (atmosphere, ocean, galactic gas clouds).These systems are often turbulent, where motion is chaotic, unpredictable, and can only be characterized through statistical analyses.Structure functions (SFs) are one such statistical analysis technique for turbulence that requires the calculation of spatial differences in properties as a function of their separation distance.By combining and then averaging these spatial differences, various types of SF can be constructed to measure physical properties of fluid flow, such as heat and energy transfers, energy density, intermittency, etc.However, calculating SFs is often a cumbersome and computationally-intensive task tailored to the specific format of a given fluid dataset.FluidSF is a flexible Python package that can be used to diagnose and analyze various physically-informative SFs from one-, two-, or three-dimensional fluid data sets.