How often have you pulled out old MCU-based project that still works fine, but you have no idea where the original source ...
The library is experimental as the functionality is not tested with hardware yet. The AD5231 is a single channel, 10 bit = 1024 step, SPI based potentiometer, the AD5235 is a dual channel version.
This library reads the channels of the MCP3302 and MCP3304 ADC convertors. The devices have 4 or 8 channels, 13 bit and communicates with SPI. The library supports both hardware SPI and software SPI.