2log (problem 3.3.6)

Percentage Accurate: 24.0% → 99.8%
Time: 10.1s
Alternatives: 9
Speedup: 17.3×

Specification

?
\[N > 1 \land N < 10^{+40}\]
\[\begin{array}{l} \\ \log \left(N + 1\right) - \log N \end{array} \]
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
	return log((N + 1.0)) - log(N);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
	return Math.log((N + 1.0)) - Math.log(N);
}
def code(N):
	return math.log((N + 1.0)) - math.log(N)
function code(N)
	return Float64(log(Float64(N + 1.0)) - log(N))
end
function tmp = code(N)
	tmp = log((N + 1.0)) - log(N);
end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(N + 1\right) - \log N
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 9 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 24.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \log \left(N + 1\right) - \log N \end{array} \]
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
	return log((N + 1.0)) - log(N);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
	return Math.log((N + 1.0)) - Math.log(N);
}
def code(N):
	return math.log((N + 1.0)) - math.log(N)
function code(N)
	return Float64(log(Float64(N + 1.0)) - log(N))
end
function tmp = code(N)
	tmp = log((N + 1.0)) - log(N);
end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\log \left(N + 1\right) - \log N
\end{array}

Alternative 1: 99.8% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \mathsf{log1p}\left(\frac{1}{N}\right) \end{array} \]
(FPCore (N) :precision binary64 (log1p (/ 1.0 N)))
double code(double N) {
	return log1p((1.0 / N));
}
public static double code(double N) {
	return Math.log1p((1.0 / N));
}
def code(N):
	return math.log1p((1.0 / N))
function code(N)
	return log1p(Float64(1.0 / N))
end
code[N_] := N[Log[1 + N[(1.0 / N), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\mathsf{log1p}\left(\frac{1}{N}\right)
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. diff-logN/A

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
    2. log-lowering-log.f64N/A

      \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \log \color{blue}{\left(\frac{N + 1}{N}\right)} \]
    4. +-lowering-+.f6427.4

      \[\leadsto \log \left(\frac{\color{blue}{N + 1}}{N}\right) \]
  4. Applied egg-rr27.4%

    \[\leadsto \color{blue}{\log \left(\frac{N + 1}{N}\right)} \]
  5. Taylor expanded in N around inf

    \[\leadsto \log \color{blue}{\left(1 + \frac{1}{N}\right)} \]
  6. Step-by-step derivation
    1. +-lowering-+.f64N/A

      \[\leadsto \log \color{blue}{\left(1 + \frac{1}{N}\right)} \]
    2. /-lowering-/.f6427.4

      \[\leadsto \log \left(1 + \color{blue}{\frac{1}{N}}\right) \]
  7. Simplified27.4%

    \[\leadsto \log \color{blue}{\left(1 + \frac{1}{N}\right)} \]
  8. Step-by-step derivation
    1. accelerator-lowering-log1p.f64N/A

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
    2. /-lowering-/.f6499.8

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\frac{1}{N}}\right) \]
  9. Applied egg-rr99.8%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(\frac{1}{N}\right)} \]
  10. Add Preprocessing

Alternative 2: 96.6% accurate, 3.1× speedup?

\[\begin{array}{l} \\ \frac{1}{\mathsf{fma}\left(N, \frac{0.5}{N} + \left(1 + \frac{0.041666666666666664}{N \cdot \left(N \cdot N\right)}\right), \frac{-0.08333333333333333}{N}\right)} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  1.0
  (fma
   N
   (+ (/ 0.5 N) (+ 1.0 (/ 0.041666666666666664 (* N (* N N)))))
   (/ -0.08333333333333333 N))))
double code(double N) {
	return 1.0 / fma(N, ((0.5 / N) + (1.0 + (0.041666666666666664 / (N * (N * N))))), (-0.08333333333333333 / N));
}
function code(N)
	return Float64(1.0 / fma(N, Float64(Float64(0.5 / N) + Float64(1.0 + Float64(0.041666666666666664 / Float64(N * Float64(N * N))))), Float64(-0.08333333333333333 / N)))
end
code[N_] := N[(1.0 / N[(N * N[(N[(0.5 / N), $MachinePrecision] + N[(1.0 + N[(0.041666666666666664 / N[(N * N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.08333333333333333 / N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\mathsf{fma}\left(N, \frac{0.5}{N} + \left(1 + \frac{0.041666666666666664}{N \cdot \left(N \cdot N\right)}\right), \frac{-0.08333333333333333}{N}\right)}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around -inf

    \[\leadsto \frac{1}{\color{blue}{-1 \cdot \left(N \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot N\right) \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
  9. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\left(-1 - \frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}\right) \cdot \left(0 - N\right)}} \]
  10. Taylor expanded in N around inf

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(\left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) - \frac{\frac{1}{12}}{{N}^{2}}\right)}} \]
  11. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(\left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)\right)}} \]
    2. distribute-lft-inN/A

      \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)}} \]
    3. distribute-rgt-neg-outN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \color{blue}{\left(\mathsf{neg}\left(N \cdot \frac{\frac{1}{12}}{{N}^{2}}\right)\right)}} \]
    4. associate-/l*N/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{N \cdot \frac{1}{12}}{{N}^{2}}}\right)\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{\color{blue}{\frac{1}{12} \cdot N}}{{N}^{2}}\right)\right)} \]
    6. unpow2N/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12} \cdot N}{\color{blue}{N \cdot N}}\right)\right)} \]
    7. associate-/r*N/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{\frac{1}{12} \cdot N}{N}}{N}}\right)\right)} \]
    8. associate-/l*N/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{\color{blue}{\frac{1}{12} \cdot \frac{N}{N}}}{N}\right)\right)} \]
    9. *-lft-identityN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12} \cdot \frac{N}{N}}{\color{blue}{1 \cdot N}}\right)\right)} \]
    10. times-fracN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{1}{12}}{1} \cdot \frac{\frac{N}{N}}{N}}\right)\right)} \]
    11. metadata-evalN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{12}} \cdot \frac{\frac{N}{N}}{N}\right)\right)} \]
    12. *-inversesN/A

      \[\leadsto \frac{1}{N \cdot \left(1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{12} \cdot \frac{\color{blue}{1}}{N}\right)\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(N, 1 + \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{24} \cdot \frac{1}{{N}^{3}}\right), \mathsf{neg}\left(\frac{1}{12} \cdot \frac{1}{N}\right)\right)}} \]
  12. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(N, \frac{0.5}{N} + \left(1 + \frac{0.041666666666666664}{N \cdot \left(N \cdot N\right)}\right), \frac{-0.08333333333333333}{N}\right)}} \]
  13. Add Preprocessing

Alternative 3: 96.6% accurate, 3.3× speedup?

\[\begin{array}{l} \\ \frac{-1}{N \cdot \mathsf{fma}\left(-0.5 + \frac{0.08333333333333333 + \frac{-0.041666666666666664}{N}}{N}, \frac{1}{N}, -1\right)} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  -1.0
  (*
   N
   (fma
    (+ -0.5 (/ (+ 0.08333333333333333 (/ -0.041666666666666664 N)) N))
    (/ 1.0 N)
    -1.0))))
double code(double N) {
	return -1.0 / (N * fma((-0.5 + ((0.08333333333333333 + (-0.041666666666666664 / N)) / N)), (1.0 / N), -1.0));
}
function code(N)
	return Float64(-1.0 / Float64(N * fma(Float64(-0.5 + Float64(Float64(0.08333333333333333 + Float64(-0.041666666666666664 / N)) / N)), Float64(1.0 / N), -1.0)))
end
code[N_] := N[(-1.0 / N[(N * N[(N[(-0.5 + N[(N[(0.08333333333333333 + N[(-0.041666666666666664 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] * N[(1.0 / N), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-1}{N \cdot \mathsf{fma}\left(-0.5 + \frac{0.08333333333333333 + \frac{-0.041666666666666664}{N}}{N}, \frac{1}{N}, -1\right)}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around -inf

    \[\leadsto \frac{1}{\color{blue}{-1 \cdot \left(N \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot N\right) \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
  9. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\left(-1 - \frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}\right) \cdot \left(0 - N\right)}} \]
  10. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 + \left(\mathsf{neg}\left(\frac{\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}}{N}\right)\right)\right)} \cdot \left(0 - N\right)} \]
    2. neg-mul-1N/A

      \[\leadsto \frac{1}{\left(-1 + \color{blue}{-1 \cdot \frac{\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}}{N}}\right) \cdot \left(0 - N\right)} \]
    3. +-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}}{N} + -1\right)} \cdot \left(0 - N\right)} \]
    4. neg-mul-1N/A

      \[\leadsto \frac{1}{\left(\color{blue}{\left(\mathsf{neg}\left(\frac{\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}}{N}\right)\right)} + -1\right) \cdot \left(0 - N\right)} \]
    5. div-invN/A

      \[\leadsto \frac{1}{\left(\left(\mathsf{neg}\left(\color{blue}{\left(\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}\right) \cdot \frac{1}{N}}\right)\right) + -1\right) \cdot \left(0 - N\right)} \]
    6. distribute-lft-neg-inN/A

      \[\leadsto \frac{1}{\left(\color{blue}{\left(\mathsf{neg}\left(\left(\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}\right)\right)\right) \cdot \frac{1}{N}} + -1\right) \cdot \left(0 - N\right)} \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(\left(\frac{1}{2} - \frac{\frac{1}{12} - \frac{\frac{1}{24}}{N}}{N}\right)\right), \frac{1}{N}, -1\right)} \cdot \left(0 - N\right)} \]
  11. Applied egg-rr97.4%

    \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(-0.5 + \frac{0.08333333333333333 + \frac{-0.041666666666666664}{N}}{N}, \frac{1}{N}, -1\right)} \cdot \left(0 - N\right)} \]
  12. Final simplification97.4%

    \[\leadsto \frac{-1}{N \cdot \mathsf{fma}\left(-0.5 + \frac{0.08333333333333333 + \frac{-0.041666666666666664}{N}}{N}, \frac{1}{N}, -1\right)} \]
  13. Add Preprocessing

Alternative 4: 96.6% accurate, 3.9× speedup?

\[\begin{array}{l} \\ \frac{1}{N \cdot \left(\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot \left(N \cdot N\right)} - -1\right)} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  1.0
  (*
   N
   (-
    (/
     (fma N (fma N 0.5 -0.08333333333333333) 0.041666666666666664)
     (* N (* N N)))
    -1.0))))
double code(double N) {
	return 1.0 / (N * ((fma(N, fma(N, 0.5, -0.08333333333333333), 0.041666666666666664) / (N * (N * N))) - -1.0));
}
function code(N)
	return Float64(1.0 / Float64(N * Float64(Float64(fma(N, fma(N, 0.5, -0.08333333333333333), 0.041666666666666664) / Float64(N * Float64(N * N))) - -1.0)))
end
code[N_] := N[(1.0 / N[(N * N[(N[(N[(N * N[(N * 0.5 + -0.08333333333333333), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] / N[(N * N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{N \cdot \left(\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot \left(N \cdot N\right)} - -1\right)}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around -inf

    \[\leadsto \frac{1}{\color{blue}{-1 \cdot \left(N \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot N\right) \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
  9. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\left(-1 - \frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}\right) \cdot \left(0 - N\right)}} \]
  10. Taylor expanded in N around 0

    \[\leadsto \frac{1}{\left(-1 - \color{blue}{\frac{\frac{1}{24} + N \cdot \left(\frac{1}{2} \cdot N - \frac{1}{12}\right)}{{N}^{3}}}\right) \cdot \left(0 - N\right)} \]
  11. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\left(-1 - \color{blue}{\frac{\frac{1}{24} + N \cdot \left(\frac{1}{2} \cdot N - \frac{1}{12}\right)}{{N}^{3}}}\right) \cdot \left(0 - N\right)} \]
    2. +-commutativeN/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\color{blue}{N \cdot \left(\frac{1}{2} \cdot N - \frac{1}{12}\right) + \frac{1}{24}}}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\color{blue}{\mathsf{fma}\left(N, \frac{1}{2} \cdot N - \frac{1}{12}, \frac{1}{24}\right)}}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    4. sub-negN/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \color{blue}{\frac{1}{2} \cdot N + \left(\mathsf{neg}\left(\frac{1}{12}\right)\right)}, \frac{1}{24}\right)}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \color{blue}{N \cdot \frac{1}{2}} + \left(\mathsf{neg}\left(\frac{1}{12}\right)\right), \frac{1}{24}\right)}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    6. metadata-evalN/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, N \cdot \frac{1}{2} + \color{blue}{\frac{-1}{12}}, \frac{1}{24}\right)}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \color{blue}{\mathsf{fma}\left(N, \frac{1}{2}, \frac{-1}{12}\right)}, \frac{1}{24}\right)}{{N}^{3}}\right) \cdot \left(0 - N\right)} \]
    8. cube-multN/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \frac{1}{2}, \frac{-1}{12}\right), \frac{1}{24}\right)}{\color{blue}{N \cdot \left(N \cdot N\right)}}\right) \cdot \left(0 - N\right)} \]
    9. unpow2N/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \frac{1}{2}, \frac{-1}{12}\right), \frac{1}{24}\right)}{N \cdot \color{blue}{{N}^{2}}}\right) \cdot \left(0 - N\right)} \]
    10. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \frac{1}{2}, \frac{-1}{12}\right), \frac{1}{24}\right)}{\color{blue}{N \cdot {N}^{2}}}\right) \cdot \left(0 - N\right)} \]
    11. unpow2N/A

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \frac{1}{2}, \frac{-1}{12}\right), \frac{1}{24}\right)}{N \cdot \color{blue}{\left(N \cdot N\right)}}\right) \cdot \left(0 - N\right)} \]
    12. *-lowering-*.f6497.4

      \[\leadsto \frac{1}{\left(-1 - \frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot \color{blue}{\left(N \cdot N\right)}}\right) \cdot \left(0 - N\right)} \]
  12. Simplified97.4%

    \[\leadsto \frac{1}{\left(-1 - \color{blue}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot \left(N \cdot N\right)}}\right) \cdot \left(0 - N\right)} \]
  13. Final simplification97.4%

    \[\leadsto \frac{1}{N \cdot \left(\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot \left(N \cdot N\right)} - -1\right)} \]
  14. Add Preprocessing

Alternative 5: 96.5% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, N + 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot N}} \end{array} \]
(FPCore (N)
 :precision binary64
 (/
  1.0
  (/
   (fma N (fma N (+ N 0.5) -0.08333333333333333) 0.041666666666666664)
   (* N N))))
double code(double N) {
	return 1.0 / (fma(N, fma(N, (N + 0.5), -0.08333333333333333), 0.041666666666666664) / (N * N));
}
function code(N)
	return Float64(1.0 / Float64(fma(N, fma(N, Float64(N + 0.5), -0.08333333333333333), 0.041666666666666664) / Float64(N * N)))
end
code[N_] := N[(1.0 / N[(N[(N * N[(N * N[(N + 0.5), $MachinePrecision] + -0.08333333333333333), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] / N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, N + 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot N}}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around -inf

    \[\leadsto \frac{1}{\color{blue}{-1 \cdot \left(N \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot N\right) \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
  9. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\left(-1 - \frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}\right) \cdot \left(0 - N\right)}} \]
  10. Taylor expanded in N around 0

    \[\leadsto \frac{1}{\color{blue}{\frac{\frac{1}{24} + N \cdot \left(N \cdot \left(\frac{1}{2} + N\right) - \frac{1}{12}\right)}{{N}^{2}}}} \]
  11. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{\frac{1}{24} + N \cdot \left(N \cdot \left(\frac{1}{2} + N\right) - \frac{1}{12}\right)}{{N}^{2}}}} \]
    2. +-commutativeN/A

      \[\leadsto \frac{1}{\frac{\color{blue}{N \cdot \left(N \cdot \left(\frac{1}{2} + N\right) - \frac{1}{12}\right) + \frac{1}{24}}}{{N}^{2}}} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\frac{\color{blue}{\mathsf{fma}\left(N, N \cdot \left(\frac{1}{2} + N\right) - \frac{1}{12}, \frac{1}{24}\right)}}{{N}^{2}}} \]
    4. sub-negN/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \color{blue}{N \cdot \left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{1}{12}\right)\right)}, \frac{1}{24}\right)}{{N}^{2}}} \]
    5. metadata-evalN/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, N \cdot \left(\frac{1}{2} + N\right) + \color{blue}{\frac{-1}{12}}, \frac{1}{24}\right)}{{N}^{2}}} \]
    6. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \color{blue}{\mathsf{fma}\left(N, \frac{1}{2} + N, \frac{-1}{12}\right)}, \frac{1}{24}\right)}{{N}^{2}}} \]
    7. +-commutativeN/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \color{blue}{N + \frac{1}{2}}, \frac{-1}{12}\right), \frac{1}{24}\right)}{{N}^{2}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, \color{blue}{N + \frac{1}{2}}, \frac{-1}{12}\right), \frac{1}{24}\right)}{{N}^{2}}} \]
    9. unpow2N/A

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, N + \frac{1}{2}, \frac{-1}{12}\right), \frac{1}{24}\right)}{\color{blue}{N \cdot N}}} \]
    10. *-lowering-*.f6497.3

      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, N + 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{\color{blue}{N \cdot N}}} \]
  12. Simplified97.3%

    \[\leadsto \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(N, \mathsf{fma}\left(N, N + 0.5, -0.08333333333333333\right), 0.041666666666666664\right)}{N \cdot N}}} \]
  13. Add Preprocessing

Alternative 6: 95.5% accurate, 7.1× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{-0.08333333333333333}{N} + \left(N + 0.5\right)} \end{array} \]
(FPCore (N)
 :precision binary64
 (/ 1.0 (+ (/ -0.08333333333333333 N) (+ N 0.5))))
double code(double N) {
	return 1.0 / ((-0.08333333333333333 / N) + (N + 0.5));
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 1.0d0 / (((-0.08333333333333333d0) / n) + (n + 0.5d0))
end function
public static double code(double N) {
	return 1.0 / ((-0.08333333333333333 / N) + (N + 0.5));
}
def code(N):
	return 1.0 / ((-0.08333333333333333 / N) + (N + 0.5))
function code(N)
	return Float64(1.0 / Float64(Float64(-0.08333333333333333 / N) + Float64(N + 0.5)))
end
function tmp = code(N)
	tmp = 1.0 / ((-0.08333333333333333 / N) + (N + 0.5));
end
code[N_] := N[(1.0 / N[(N[(-0.08333333333333333 / N), $MachinePrecision] + N[(N + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\frac{-0.08333333333333333}{N} + \left(N + 0.5\right)}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around -inf

    \[\leadsto \frac{1}{\color{blue}{-1 \cdot \left(N \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)\right)}} \]
  8. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot N\right) \cdot \left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(-1 \cdot \frac{\frac{1}{2} + -1 \cdot \frac{\frac{1}{12} - \frac{1}{24} \cdot \frac{1}{N}}{N}}{N} - 1\right) \cdot \left(-1 \cdot N\right)}} \]
  9. Simplified97.4%

    \[\leadsto \frac{1}{\color{blue}{\left(-1 - \frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}\right) \cdot \left(0 - N\right)}} \]
  10. Taylor expanded in N around inf

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(\left(1 + \frac{1}{2} \cdot \frac{1}{N}\right) - \frac{\frac{1}{12}}{{N}^{2}}\right)}} \]
  11. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{1}{N \cdot \color{blue}{\left(\left(1 + \frac{1}{2} \cdot \frac{1}{N}\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)\right)}} \]
    2. distribute-lft-inN/A

      \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{1}{2} \cdot \frac{1}{N}\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)}} \]
    3. distribute-rgt-inN/A

      \[\leadsto \frac{1}{\color{blue}{\left(1 \cdot N + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N\right)} + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    4. *-lft-identityN/A

      \[\leadsto \frac{1}{\left(\color{blue}{N} + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    5. associate-*l*N/A

      \[\leadsto \frac{1}{\left(N + \color{blue}{\frac{1}{2} \cdot \left(\frac{1}{N} \cdot N\right)}\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    6. lft-mult-inverseN/A

      \[\leadsto \frac{1}{\left(N + \frac{1}{2} \cdot \color{blue}{1}\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    7. metadata-evalN/A

      \[\leadsto \frac{1}{\left(N + \color{blue}{\frac{1}{2}}\right) + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    8. +-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + N\right)} + N \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{12}}{{N}^{2}}\right)\right)} \]
    9. distribute-rgt-neg-outN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \color{blue}{\left(\mathsf{neg}\left(N \cdot \frac{\frac{1}{12}}{{N}^{2}}\right)\right)}} \]
    10. associate-/l*N/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{N \cdot \frac{1}{12}}{{N}^{2}}}\right)\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{\color{blue}{\frac{1}{12} \cdot N}}{{N}^{2}}\right)\right)} \]
    12. unpow2N/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12} \cdot N}{\color{blue}{N \cdot N}}\right)\right)} \]
    13. associate-/r*N/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{\frac{1}{12} \cdot N}{N}}{N}}\right)\right)} \]
    14. associate-/l*N/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{\color{blue}{\frac{1}{12} \cdot \frac{N}{N}}}{N}\right)\right)} \]
    15. *-lft-identityN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{\frac{1}{12} \cdot \frac{N}{N}}{\color{blue}{1 \cdot N}}\right)\right)} \]
    16. times-fracN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{1}{12}}{1} \cdot \frac{\frac{N}{N}}{N}}\right)\right)} \]
    17. metadata-evalN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{12}} \cdot \frac{\frac{N}{N}}{N}\right)\right)} \]
    18. *-inversesN/A

      \[\leadsto \frac{1}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{1}{12} \cdot \frac{\color{blue}{1}}{N}\right)\right)} \]
    19. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + N\right) + \left(\mathsf{neg}\left(\frac{1}{12} \cdot \frac{1}{N}\right)\right)}} \]
  12. Simplified95.8%

    \[\leadsto \frac{1}{\color{blue}{\left(N + 0.5\right) + \frac{-0.08333333333333333}{N}}} \]
  13. Final simplification95.8%

    \[\leadsto \frac{1}{\frac{-0.08333333333333333}{N} + \left(N + 0.5\right)} \]
  14. Add Preprocessing

Alternative 7: 92.9% accurate, 13.8× speedup?

\[\begin{array}{l} \\ \frac{1}{N + 0.5} \end{array} \]
(FPCore (N) :precision binary64 (/ 1.0 (+ N 0.5)))
double code(double N) {
	return 1.0 / (N + 0.5);
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 1.0d0 / (n + 0.5d0)
end function
public static double code(double N) {
	return 1.0 / (N + 0.5);
}
def code(N):
	return 1.0 / (N + 0.5)
function code(N)
	return Float64(1.0 / Float64(N + 0.5))
end
function tmp = code(N)
	tmp = 1.0 / (N + 0.5);
end
code[N_] := N[(1.0 / N[(N + 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{N + 0.5}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around inf

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{1}{2} \cdot \frac{1}{N}\right)}} \]
  8. Step-by-step derivation
    1. distribute-rgt-inN/A

      \[\leadsto \frac{1}{\color{blue}{1 \cdot N + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N}} \]
    2. *-lft-identityN/A

      \[\leadsto \frac{1}{\color{blue}{N} + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N} \]
    3. associate-*l*N/A

      \[\leadsto \frac{1}{N + \color{blue}{\frac{1}{2} \cdot \left(\frac{1}{N} \cdot N\right)}} \]
    4. lft-mult-inverseN/A

      \[\leadsto \frac{1}{N + \frac{1}{2} \cdot \color{blue}{1}} \]
    5. metadata-evalN/A

      \[\leadsto \frac{1}{N + \color{blue}{\frac{1}{2}}} \]
    6. +-lowering-+.f6492.8

      \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  9. Simplified92.8%

    \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  10. Add Preprocessing

Alternative 8: 84.3% accurate, 17.3× speedup?

\[\begin{array}{l} \\ \frac{1}{N} \end{array} \]
(FPCore (N) :precision binary64 (/ 1.0 N))
double code(double N) {
	return 1.0 / N;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 1.0d0 / n
end function
public static double code(double N) {
	return 1.0 / N;
}
def code(N):
	return 1.0 / N
function code(N)
	return Float64(1.0 / N)
end
function tmp = code(N)
	tmp = 1.0 / N;
end
code[N_] := N[(1.0 / N), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{N}
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{1}{N}} \]
  4. Step-by-step derivation
    1. /-lowering-/.f6483.9

      \[\leadsto \color{blue}{\frac{1}{N}} \]
  5. Simplified83.9%

    \[\leadsto \color{blue}{\frac{1}{N}} \]
  6. Add Preprocessing

Alternative 9: 9.9% accurate, 207.0× speedup?

\[\begin{array}{l} \\ 2 \end{array} \]
(FPCore (N) :precision binary64 2.0)
double code(double N) {
	return 2.0;
}
real(8) function code(n)
    real(8), intent (in) :: n
    code = 2.0d0
end function
public static double code(double N) {
	return 2.0;
}
def code(N):
	return 2.0
function code(N)
	return 2.0
end
function tmp = code(N)
	tmp = 2.0;
end
code[N_] := 2.0
\begin{array}{l}

\\
2
\end{array}
Derivation
  1. Initial program 24.4%

    \[\log \left(N + 1\right) - \log N \]
  2. Add Preprocessing
  3. Taylor expanded in N around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{\frac{1}{3}}{{N}^{2}}\right) - \left(\frac{1}{2} \cdot \frac{1}{N} + \frac{1}{4} \cdot \frac{1}{{N}^{3}}\right)}{N}} \]
  4. Simplified97.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}{N}} \]
  5. Step-by-step derivation
    1. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    2. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    4. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{\color{blue}{1 + \frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \color{blue}{\frac{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}{N}}}} \]
    6. --lowering--.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\color{blue}{\frac{-1}{2} - \frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \color{blue}{\frac{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}{N}}}{N}}} \]
    8. +-lowering-+.f64N/A

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{\frac{-1}{2} - \frac{\color{blue}{\frac{\frac{1}{4}}{N} + \frac{-1}{3}}}{N}}{N}}} \]
    9. /-lowering-/.f6497.0

      \[\leadsto \frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\color{blue}{\frac{0.25}{N}} + -0.3333333333333333}{N}}{N}}} \]
  6. Applied egg-rr97.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{N}{1 + \frac{-0.5 - \frac{\frac{0.25}{N} + -0.3333333333333333}{N}}{N}}}} \]
  7. Taylor expanded in N around inf

    \[\leadsto \frac{1}{\color{blue}{N \cdot \left(1 + \frac{1}{2} \cdot \frac{1}{N}\right)}} \]
  8. Step-by-step derivation
    1. distribute-rgt-inN/A

      \[\leadsto \frac{1}{\color{blue}{1 \cdot N + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N}} \]
    2. *-lft-identityN/A

      \[\leadsto \frac{1}{\color{blue}{N} + \left(\frac{1}{2} \cdot \frac{1}{N}\right) \cdot N} \]
    3. associate-*l*N/A

      \[\leadsto \frac{1}{N + \color{blue}{\frac{1}{2} \cdot \left(\frac{1}{N} \cdot N\right)}} \]
    4. lft-mult-inverseN/A

      \[\leadsto \frac{1}{N + \frac{1}{2} \cdot \color{blue}{1}} \]
    5. metadata-evalN/A

      \[\leadsto \frac{1}{N + \color{blue}{\frac{1}{2}}} \]
    6. +-lowering-+.f6492.8

      \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  9. Simplified92.8%

    \[\leadsto \frac{1}{\color{blue}{N + 0.5}} \]
  10. Taylor expanded in N around 0

    \[\leadsto \color{blue}{2} \]
  11. Step-by-step derivation
    1. Simplified9.9%

      \[\leadsto \color{blue}{2} \]
    2. Add Preprocessing

    Developer Target 1: 99.8% accurate, 1.8× speedup?

    \[\begin{array}{l} \\ \mathsf{log1p}\left(\frac{1}{N}\right) \end{array} \]
    (FPCore (N) :precision binary64 (log1p (/ 1.0 N)))
    double code(double N) {
    	return log1p((1.0 / N));
    }
    
    public static double code(double N) {
    	return Math.log1p((1.0 / N));
    }
    
    def code(N):
    	return math.log1p((1.0 / N))
    
    function code(N)
    	return log1p(Float64(1.0 / N))
    end
    
    code[N_] := N[Log[1 + N[(1.0 / N), $MachinePrecision]], $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{log1p}\left(\frac{1}{N}\right)
    \end{array}
    

    Developer Target 2: 26.7% accurate, 1.8× speedup?

    \[\begin{array}{l} \\ \log \left(1 + \frac{1}{N}\right) \end{array} \]
    (FPCore (N) :precision binary64 (log (+ 1.0 (/ 1.0 N))))
    double code(double N) {
    	return log((1.0 + (1.0 / N)));
    }
    
    real(8) function code(n)
        real(8), intent (in) :: n
        code = log((1.0d0 + (1.0d0 / n)))
    end function
    
    public static double code(double N) {
    	return Math.log((1.0 + (1.0 / N)));
    }
    
    def code(N):
    	return math.log((1.0 + (1.0 / N)))
    
    function code(N)
    	return log(Float64(1.0 + Float64(1.0 / N)))
    end
    
    function tmp = code(N)
    	tmp = log((1.0 + (1.0 / N)));
    end
    
    code[N_] := N[Log[N[(1.0 + N[(1.0 / N), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \log \left(1 + \frac{1}{N}\right)
    \end{array}
    

    Developer Target 3: 96.1% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \left(\left(\frac{1}{N} + \frac{-1}{2 \cdot {N}^{2}}\right) + \frac{1}{3 \cdot {N}^{3}}\right) + \frac{-1}{4 \cdot {N}^{4}} \end{array} \]
    (FPCore (N)
     :precision binary64
     (+
      (+ (+ (/ 1.0 N) (/ -1.0 (* 2.0 (pow N 2.0)))) (/ 1.0 (* 3.0 (pow N 3.0))))
      (/ -1.0 (* 4.0 (pow N 4.0)))))
    double code(double N) {
    	return (((1.0 / N) + (-1.0 / (2.0 * pow(N, 2.0)))) + (1.0 / (3.0 * pow(N, 3.0)))) + (-1.0 / (4.0 * pow(N, 4.0)));
    }
    
    real(8) function code(n)
        real(8), intent (in) :: n
        code = (((1.0d0 / n) + ((-1.0d0) / (2.0d0 * (n ** 2.0d0)))) + (1.0d0 / (3.0d0 * (n ** 3.0d0)))) + ((-1.0d0) / (4.0d0 * (n ** 4.0d0)))
    end function
    
    public static double code(double N) {
    	return (((1.0 / N) + (-1.0 / (2.0 * Math.pow(N, 2.0)))) + (1.0 / (3.0 * Math.pow(N, 3.0)))) + (-1.0 / (4.0 * Math.pow(N, 4.0)));
    }
    
    def code(N):
    	return (((1.0 / N) + (-1.0 / (2.0 * math.pow(N, 2.0)))) + (1.0 / (3.0 * math.pow(N, 3.0)))) + (-1.0 / (4.0 * math.pow(N, 4.0)))
    
    function code(N)
    	return Float64(Float64(Float64(Float64(1.0 / N) + Float64(-1.0 / Float64(2.0 * (N ^ 2.0)))) + Float64(1.0 / Float64(3.0 * (N ^ 3.0)))) + Float64(-1.0 / Float64(4.0 * (N ^ 4.0))))
    end
    
    function tmp = code(N)
    	tmp = (((1.0 / N) + (-1.0 / (2.0 * (N ^ 2.0)))) + (1.0 / (3.0 * (N ^ 3.0)))) + (-1.0 / (4.0 * (N ^ 4.0)));
    end
    
    code[N_] := N[(N[(N[(N[(1.0 / N), $MachinePrecision] + N[(-1.0 / N[(2.0 * N[Power[N, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(3.0 * N[Power[N, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / N[(4.0 * N[Power[N, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\left(\frac{1}{N} + \frac{-1}{2 \cdot {N}^{2}}\right) + \frac{1}{3 \cdot {N}^{3}}\right) + \frac{-1}{4 \cdot {N}^{4}}
    \end{array}
    

    Reproduce

    ?
    herbie shell --seed 2024194 
    (FPCore (N)
      :name "2log (problem 3.3.6)"
      :precision binary64
      :pre (and (> N 1.0) (< N 1e+40))
    
      :alt
      (! :herbie-platform default (log1p (/ 1 N)))
    
      :alt
      (! :herbie-platform default (log (+ 1 (/ 1 N))))
    
      :alt
      (! :herbie-platform default (+ (/ 1 N) (/ -1 (* 2 (pow N 2))) (/ 1 (* 3 (pow N 3))) (/ -1 (* 4 (pow N 4)))))
    
      (- (log (+ N 1.0)) (log N)))