16.2.2 Numbers

Python evaluates operations on numbers directly and introduces unavoidable rounding errors. These would obstruct all symbolic calculations. This is avoided when we sympify numbers:

1/3  # returns 0.3333333333333333
sympify(1)/sympify(3)  # returns '1/3'

The sympify command converts an integer to an object of type sympy.core.numbers.Integer.

Instead of writing 1/3 as an operation of two integers, it can also be represented directly as a rational number by Rational(1,3).