Average Error: 29.6 → 0.1
Time: 4.0s
Precision: 64
\[\log \left(N + 1\right) - \log N\]
\[\begin{array}{l} \mathbf{if}\;N \le 13931.9619516847724:\\ \;\;\;\;\log \left(\frac{N + 1}{N}\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(e^{\frac{1}{{N}^{2}}}\right) \cdot \frac{0.333333333333333315}{N} + \left(\frac{1}{N} - \frac{\frac{0.5}{N}}{N}\right)\\ \end{array}\]
\log \left(N + 1\right) - \log N
\begin{array}{l}
\mathbf{if}\;N \le 13931.9619516847724:\\
\;\;\;\;\log \left(\frac{N + 1}{N}\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(e^{\frac{1}{{N}^{2}}}\right) \cdot \frac{0.333333333333333315}{N} + \left(\frac{1}{N} - \frac{\frac{0.5}{N}}{N}\right)\\

\end{array}
double f(double N) {
        double r41091 = N;
        double r41092 = 1.0;
        double r41093 = r41091 + r41092;
        double r41094 = log(r41093);
        double r41095 = log(r41091);
        double r41096 = r41094 - r41095;
        return r41096;
}

double f(double N) {
        double r41097 = N;
        double r41098 = 13931.961951684772;
        bool r41099 = r41097 <= r41098;
        double r41100 = 1.0;
        double r41101 = r41097 + r41100;
        double r41102 = r41101 / r41097;
        double r41103 = log(r41102);
        double r41104 = 1.0;
        double r41105 = 2.0;
        double r41106 = pow(r41097, r41105);
        double r41107 = r41104 / r41106;
        double r41108 = exp(r41107);
        double r41109 = log(r41108);
        double r41110 = 0.3333333333333333;
        double r41111 = r41110 / r41097;
        double r41112 = r41109 * r41111;
        double r41113 = r41100 / r41097;
        double r41114 = 0.5;
        double r41115 = r41114 / r41097;
        double r41116 = r41115 / r41097;
        double r41117 = r41113 - r41116;
        double r41118 = r41112 + r41117;
        double r41119 = r41099 ? r41103 : r41118;
        return r41119;
}

Error

Bits error versus N

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if N < 13931.961951684772

    1. Initial program 0.1

      \[\log \left(N + 1\right) - \log N\]
    2. Using strategy rm
    3. Applied diff-log0.1

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)}\]

    if 13931.961951684772 < N

    1. Initial program 59.5

      \[\log \left(N + 1\right) - \log N\]
    2. Taylor expanded around inf 0.0

      \[\leadsto \color{blue}{\left(0.333333333333333315 \cdot \frac{1}{{N}^{3}} + 1 \cdot \frac{1}{N}\right) - 0.5 \cdot \frac{1}{{N}^{2}}}\]
    3. Simplified0.0

      \[\leadsto \color{blue}{\frac{1}{{N}^{2}} \cdot \left(\frac{0.333333333333333315}{N} - 0.5\right) + \frac{1}{N}}\]
    4. Using strategy rm
    5. Applied sub-neg0.0

      \[\leadsto \frac{1}{{N}^{2}} \cdot \color{blue}{\left(\frac{0.333333333333333315}{N} + \left(-0.5\right)\right)} + \frac{1}{N}\]
    6. Applied distribute-lft-in0.0

      \[\leadsto \color{blue}{\left(\frac{1}{{N}^{2}} \cdot \frac{0.333333333333333315}{N} + \frac{1}{{N}^{2}} \cdot \left(-0.5\right)\right)} + \frac{1}{N}\]
    7. Applied associate-+l+0.0

      \[\leadsto \color{blue}{\frac{1}{{N}^{2}} \cdot \frac{0.333333333333333315}{N} + \left(\frac{1}{{N}^{2}} \cdot \left(-0.5\right) + \frac{1}{N}\right)}\]
    8. Simplified0.0

      \[\leadsto \frac{1}{{N}^{2}} \cdot \frac{0.333333333333333315}{N} + \color{blue}{\left(\frac{1}{N} - \frac{\frac{0.5}{N}}{N}\right)}\]
    9. Using strategy rm
    10. Applied add-log-exp0.0

      \[\leadsto \color{blue}{\log \left(e^{\frac{1}{{N}^{2}}}\right)} \cdot \frac{0.333333333333333315}{N} + \left(\frac{1}{N} - \frac{\frac{0.5}{N}}{N}\right)\]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.1

    \[\leadsto \begin{array}{l} \mathbf{if}\;N \le 13931.9619516847724:\\ \;\;\;\;\log \left(\frac{N + 1}{N}\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(e^{\frac{1}{{N}^{2}}}\right) \cdot \frac{0.333333333333333315}{N} + \left(\frac{1}{N} - \frac{\frac{0.5}{N}}{N}\right)\\ \end{array}\]

Reproduce

herbie shell --seed 2020056 
(FPCore (N)
  :name "2log (problem 3.3.6)"
  :precision binary64
  (- (log (+ N 1)) (log N)))