Hands-On Design Patterns and Best Practices with Julia

Symata.jl

The Symata.jl package provides support for Fibonacci polynomials. As we may have realized, the implementation of Fibonacci polynomials is also recursive just like the Fibonacci sequence problem we discussed earlier in this section. Symata.jl uses the Memoize.jl package to create the _fibpoly function as follows:

fibpoly(n::Int) = _fib_poly(n)let myzero = 0, myone = 1, xvar = Polynomials.Poly([myzero,myone]), zerovar = Polynomials.Poly([myzero]), onevar = Polynomials.Poly([myone])    global _fib_poly    @memoize function _fib_poly(n::Int)        if n == 0            return zerovar        elseif n == 1            return onevar        else            return xvar * _fib_poly(n-1) + _fib_poly(n-2)        end    endend