growpacity computes mean opacities for dust populations with arbitrary composition, maximum grain size a_max, and size distribution power-law index q. It uses optool (ascl:2104.010) to compute frequency-dependent absorption and scattering coefficients over a configurable parameter grid, which are averaged into Rosseland and Planck mean opacities as functions of a_max, q, and temperature. The results are stored in lightweight tables that can be efficiently interpolated via provided C and Python interfaces, enabling use in high-performance radiation hydrodynamics and dust evolution simulations with dynamically varying grain size distributions.

Simframe facilitates setting up and running scientific simulations. The package organizes simulation data into fields derived from NumPy arrays, allowing users to define variables, parameters, and differential equations within a unified simulation frame. It includes numerical integration schemes—both explicit and implicit—to evolve model variables and supports adaptive step sizes and custom integration methods. simframe also provides tools for structuring simulation components, updating variables during integration, and writing or reading output data files. Example applications include solving coupled differential equations and modeling dynamical systems such as N-body problems or compartmental models.

The DustPyLib library contains auxiliary modules for the dust evolution software DustPy (ascl:2207.016), which simulates the evolution of dust and gas in protoplanetary disks. DustPyLib includes interfaces to radiative transfer codes and modules with extensions to the DustPy defaults.

DustPy simulates the radial evolution of gas and dust in protoplanetary disks, involving viscous evolution of the gas disk and advection and diffusion of the dust disk, as well as dust growth by solving the Smoluchowski equation. The package provides a standard simulation and the ability to plot results, and also allows modification of the initial conditions for dust, gas, the grid, and the central star.