crv_coeffs.py 文件源码

def create_expression(n):
    if n not in coeffs:
        raise ValueError("Don't have coefficients for {}".format(n))

    from sympy import Float, Add

    p = coeffs[n]['p']
    q = coeffs[n]['q']

    # Don't use Poly here, it loses precision
    num = Add(*[Float(p[i])*t**i for i in range(n+1)])
    den = Add(*[Float(q[i])*t**i for i in range(n+1)])

    return num/den