How symbolic value is stored in Matlab

Question

A character value takes 112 bytes of memory using Matlab (Symbolic Math toolbox). This can be seen with the whos command.

I know that the floating point value (in the Matlab numerical structure) is stored in accordance with 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 storage details of symbolic numbers? What standard is used?

Answer 1

The core of the symbolic math toolbar is mupad, software developed by the mupad research group at paderborn university. If you want a general idea of ​​how symbolic math works in Matlab, try finding it there.

The sym object itself is a kind of wrapper that transfers data to matlab. You can easily prove that sym does not contain all the necessary information. Create a constant of 1000 to store this information, it takes more than 112 bytes, but your sym is still the same size.