How is a symbolic value stored in Matlab

Question

A symbolic value occupies 112 bytes of memory with Matlab (Symbolic Math toolbox). One can see this via the whos command.

I know that a floating-point value (in the numerical framework of Matlab) is stored according to the IEEE 754 standard. So, with 8 bytes (double precision): 52 bits for the mantissa, one bit for the sign, and 11 bits for the exponent.

What about the details of the storage of symbolic numbers? What standard is used?

Answer 1

The core of the symbolic math toolbox is mupad, a software which was developed by the "mupad research group" at the university of paderborn. If you want to get a rough idea how symbolic math works in Matlab works try searching there.

The sym object itself is some kind of wrapper porting the data into matlab. You can easily prove that the sym does not contain all relevant information. Create a 1000 digits constant, to hold this information more than 112 bytes are required but your sym still has the same size.