241 Numeric vs. symbolic operations, entering vectors Matlab can either operate numerically or symbolically . Numeric operations use floating point numbers with about 15 digits and an exponent between -308 and 308. They are very fast, but each operation has a certain roundoff error, and these roundoff errors can accumulate. Matlab displays numeric vectors without brackets.
Symbolic operations use integers, fractions, roots and symbolic variables.
Symbolic operations will give you an exact answer , but for more complicated problems symbolic operations are very slow and lead to huge expressions. Matlab displays symbolic vectors with brackets. Here the functions are specified as strings or a symbolic expressions . Now expr2 should be the same as expr , but it looks very different.