Analog computing is much more efficient than digital one. For example, you can perform a multiplication of two numbers using a single transistor (or memristor/e

Analog computing is much more efficient than digital one. For example, you can perform a multiplication of two numbers using a single transistor (or memristor/etc), if you only need the equivalent of 8 bits precision. An 8 bit digital multiplier needs about a thousand transistors. The other major advantage is that you don't need to move data from memory to the processor - once you put your data into memory, you can do computation right there on the spot ('in memory computing').