Falkner and Boettcher, Equation (20:1,3)

Percentage Accurate: 99.3% → 99.3%
Time: 2.9s
Alternatives: 6
Speedup: 1.4×

Specification

?
\[\begin{array}{l} \\ \frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \end{array} \]
(FPCore (v t)
 :precision binary64
 (/
  (- 1.0 (* 5.0 (* v v)))
  (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
double code(double v, double t) {
	return (1.0 - (5.0 * (v * v))) / (((((double) M_PI) * t) * sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
}
public static double code(double v, double t) {
	return (1.0 - (5.0 * (v * v))) / (((Math.PI * t) * Math.sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
}
def code(v, t):
	return (1.0 - (5.0 * (v * v))) / (((math.pi * t) * math.sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)))
function code(v, t)
	return Float64(Float64(1.0 - Float64(5.0 * Float64(v * v))) / Float64(Float64(Float64(pi * t) * sqrt(Float64(2.0 * Float64(1.0 - Float64(3.0 * Float64(v * v)))))) * Float64(1.0 - Float64(v * v))))
end
function tmp = code(v, t)
	tmp = (1.0 - (5.0 * (v * v))) / (((pi * t) * sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
end
code[v_, t_] := N[(N[(1.0 - N[(5.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[(Pi * t), $MachinePrecision] * N[Sqrt[N[(2.0 * N[(1.0 - N[(3.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}

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 6 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: 99.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \end{array} \]
(FPCore (v t)
 :precision binary64
 (/
  (- 1.0 (* 5.0 (* v v)))
  (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
double code(double v, double t) {
	return (1.0 - (5.0 * (v * v))) / (((((double) M_PI) * t) * sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
}
public static double code(double v, double t) {
	return (1.0 - (5.0 * (v * v))) / (((Math.PI * t) * Math.sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
}
def code(v, t):
	return (1.0 - (5.0 * (v * v))) / (((math.pi * t) * math.sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)))
function code(v, t)
	return Float64(Float64(1.0 - Float64(5.0 * Float64(v * v))) / Float64(Float64(Float64(pi * t) * sqrt(Float64(2.0 * Float64(1.0 - Float64(3.0 * Float64(v * v)))))) * Float64(1.0 - Float64(v * v))))
end
function tmp = code(v, t)
	tmp = (1.0 - (5.0 * (v * v))) / (((pi * t) * sqrt((2.0 * (1.0 - (3.0 * (v * v)))))) * (1.0 - (v * v)));
end
code[v_, t_] := N[(N[(1.0 - N[(5.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(N[(Pi * t), $MachinePrecision] * N[Sqrt[N[(2.0 * N[(1.0 - N[(3.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}

Alternative 1: 99.3% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \sqrt{2} \cdot \pi\\ \frac{\mathsf{fma}\left(\frac{v \cdot v}{t\_1}, -2.5, \frac{1}{t\_1}\right)}{t} \end{array} \end{array} \]
(FPCore (v t)
 :precision binary64
 (let* ((t_1 (* (sqrt 2.0) PI))) (/ (fma (/ (* v v) t_1) -2.5 (/ 1.0 t_1)) t)))
double code(double v, double t) {
	double t_1 = sqrt(2.0) * ((double) M_PI);
	return fma(((v * v) / t_1), -2.5, (1.0 / t_1)) / t;
}
function code(v, t)
	t_1 = Float64(sqrt(2.0) * pi)
	return Float64(fma(Float64(Float64(v * v) / t_1), -2.5, Float64(1.0 / t_1)) / t)
end
code[v_, t_] := Block[{t$95$1 = N[(N[Sqrt[2.0], $MachinePrecision] * Pi), $MachinePrecision]}, N[(N[(N[(N[(v * v), $MachinePrecision] / t$95$1), $MachinePrecision] * -2.5 + N[(1.0 / t$95$1), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \sqrt{2} \cdot \pi\\
\frac{\mathsf{fma}\left(\frac{v \cdot v}{t\_1}, -2.5, \frac{1}{t\_1}\right)}{t}
\end{array}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{-5}{2} \cdot \frac{{v}^{2}}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)} + \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{{v}^{2}}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)} \cdot \frac{-5}{2} + \frac{\color{blue}{1}}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)} \]
    2. lower-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{{v}^{2}}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}, \color{blue}{\frac{-5}{2}}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    3. lower-/.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{{v}^{2}}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    4. pow2N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    5. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    7. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    9. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    10. lower-sqrt.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    11. lift-PI.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \pi\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    12. lower-/.f64N/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \pi\right) \cdot t}, \frac{-5}{2}, \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \pi\right) \cdot t}, \frac{-5}{2}, \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot t}\right) \]
  4. Applied rewrites98.9%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{v \cdot v}{\left(\sqrt{2} \cdot \pi\right) \cdot t}, -2.5, \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}\right)} \]
  5. Taylor expanded in t around 0

    \[\leadsto \frac{\frac{-5}{2} \cdot \frac{{v}^{2}}{\mathsf{PI}\left(\right) \cdot \sqrt{2}} + \frac{1}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}}{\color{blue}{t}} \]
  6. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{\frac{-5}{2} \cdot \frac{{v}^{2}}{\mathsf{PI}\left(\right) \cdot \sqrt{2}} + \frac{1}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}}{t} \]
  7. Applied rewrites99.3%

    \[\leadsto \frac{\mathsf{fma}\left(\frac{v \cdot v}{\sqrt{2} \cdot \pi}, -2.5, \frac{1}{\sqrt{2} \cdot \pi}\right)}{\color{blue}{t}} \]
  8. Add Preprocessing

Alternative 2: 98.8% accurate, 3.3× speedup?

\[\begin{array}{l} \\ \frac{\frac{1}{\sqrt{2} \cdot \pi}}{t} \end{array} \]
(FPCore (v t) :precision binary64 (/ (/ 1.0 (* (sqrt 2.0) PI)) t))
double code(double v, double t) {
	return (1.0 / (sqrt(2.0) * ((double) M_PI))) / t;
}
public static double code(double v, double t) {
	return (1.0 / (Math.sqrt(2.0) * Math.PI)) / t;
}
def code(v, t):
	return (1.0 / (math.sqrt(2.0) * math.pi)) / t
function code(v, t)
	return Float64(Float64(1.0 / Float64(sqrt(2.0) * pi)) / t)
end
function tmp = code(v, t)
	tmp = (1.0 / (sqrt(2.0) * pi)) / t;
end
code[v_, t_] := N[(N[(1.0 / N[(N[Sqrt[2.0], $MachinePrecision] * Pi), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{1}{\sqrt{2} \cdot \pi}}{t}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    3. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    4. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    5. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    6. lower-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    7. lift-PI.f6498.3

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \]
  4. Applied rewrites98.3%

    \[\leadsto \color{blue}{\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
  5. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
    2. lift-*.f64N/A

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

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \pi}}{\color{blue}{t}} \]
    4. lift-PI.f64N/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    5. lift-*.f64N/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    6. lift-sqrt.f64N/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    7. *-commutativeN/A

      \[\leadsto \frac{\frac{1}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}}{t} \]
    8. lower-/.f64N/A

      \[\leadsto \frac{\frac{1}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}}{\color{blue}{t}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{\frac{1}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}}{t} \]
    10. *-commutativeN/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    11. lift-sqrt.f64N/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    12. lift-*.f64N/A

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t} \]
    13. lift-PI.f6498.8

      \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \pi}}{t} \]
  6. Applied rewrites98.8%

    \[\leadsto \frac{\frac{1}{\sqrt{2} \cdot \pi}}{\color{blue}{t}} \]
  7. Add Preprocessing

Alternative 3: 98.4% accurate, 3.3× speedup?

\[\begin{array}{l} \\ \frac{\frac{1}{t}}{\sqrt{2} \cdot \pi} \end{array} \]
(FPCore (v t) :precision binary64 (/ (/ 1.0 t) (* (sqrt 2.0) PI)))
double code(double v, double t) {
	return (1.0 / t) / (sqrt(2.0) * ((double) M_PI));
}
public static double code(double v, double t) {
	return (1.0 / t) / (Math.sqrt(2.0) * Math.PI);
}
def code(v, t):
	return (1.0 / t) / (math.sqrt(2.0) * math.pi)
function code(v, t)
	return Float64(Float64(1.0 / t) / Float64(sqrt(2.0) * pi))
end
function tmp = code(v, t)
	tmp = (1.0 / t) / (sqrt(2.0) * pi);
end
code[v_, t_] := N[(N[(1.0 / t), $MachinePrecision] / N[(N[Sqrt[2.0], $MachinePrecision] * Pi), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{1}{t}}{\sqrt{2} \cdot \pi}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    3. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    4. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    5. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    6. lower-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    7. lift-PI.f6498.3

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \]
  4. Applied rewrites98.3%

    \[\leadsto \color{blue}{\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
  5. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot \color{blue}{t}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \color{blue}{\left(\sqrt{2} \cdot \pi\right)}} \]
    3. lift-PI.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)} \]
    5. lift-sqrt.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    6. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \color{blue}{\sqrt{2}}\right)} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    8. associate-/r*N/A

      \[\leadsto \frac{\frac{1}{t}}{\color{blue}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{\frac{1}{t}}{\color{blue}{\mathsf{PI}\left(\right) \cdot \sqrt{2}}} \]
    10. lower-/.f64N/A

      \[\leadsto \frac{\frac{1}{t}}{\color{blue}{\mathsf{PI}\left(\right)} \cdot \sqrt{2}} \]
    11. *-commutativeN/A

      \[\leadsto \frac{\frac{1}{t}}{\sqrt{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}} \]
    12. lift-sqrt.f64N/A

      \[\leadsto \frac{\frac{1}{t}}{\sqrt{2} \cdot \mathsf{PI}\left(\right)} \]
    13. lift-*.f64N/A

      \[\leadsto \frac{\frac{1}{t}}{\sqrt{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}} \]
    14. lift-PI.f6498.4

      \[\leadsto \frac{\frac{1}{t}}{\sqrt{2} \cdot \pi} \]
  6. Applied rewrites98.4%

    \[\leadsto \frac{\frac{1}{t}}{\color{blue}{\sqrt{2} \cdot \pi}} \]
  7. Add Preprocessing

Alternative 4: 98.3% accurate, 3.4× speedup?

\[\begin{array}{l} \\ \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \end{array} \]
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (sqrt 2.0) PI) t)))
double code(double v, double t) {
	return 1.0 / ((sqrt(2.0) * ((double) M_PI)) * t);
}
public static double code(double v, double t) {
	return 1.0 / ((Math.sqrt(2.0) * Math.PI) * t);
}
def code(v, t):
	return 1.0 / ((math.sqrt(2.0) * math.pi) * t)
function code(v, t)
	return Float64(1.0 / Float64(Float64(sqrt(2.0) * pi) * t))
end
function tmp = code(v, t)
	tmp = 1.0 / ((sqrt(2.0) * pi) * t);
end
code[v_, t_] := N[(1.0 / N[(N[(N[Sqrt[2.0], $MachinePrecision] * Pi), $MachinePrecision] * t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    3. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    4. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    5. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    6. lower-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    7. lift-PI.f6498.3

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \]
  4. Applied rewrites98.3%

    \[\leadsto \color{blue}{\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
  5. Add Preprocessing

Alternative 5: 98.2% accurate, 3.4× speedup?

\[\begin{array}{l} \\ \frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}} \end{array} \]
(FPCore (v t) :precision binary64 (/ 1.0 (* (* PI t) (sqrt 2.0))))
double code(double v, double t) {
	return 1.0 / ((((double) M_PI) * t) * sqrt(2.0));
}
public static double code(double v, double t) {
	return 1.0 / ((Math.PI * t) * Math.sqrt(2.0));
}
def code(v, t):
	return 1.0 / ((math.pi * t) * math.sqrt(2.0))
function code(v, t)
	return Float64(1.0 / Float64(Float64(pi * t) * sqrt(2.0)))
end
function tmp = code(v, t)
	tmp = 1.0 / ((pi * t) * sqrt(2.0));
end
code[v_, t_] := N[(1.0 / N[(N[(Pi * t), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    3. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    4. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    5. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    6. lower-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    7. lift-PI.f6498.3

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \]
  4. Applied rewrites98.3%

    \[\leadsto \color{blue}{\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
  5. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot \color{blue}{t}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \color{blue}{\left(\sqrt{2} \cdot \pi\right)}} \]
    3. lift-PI.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)} \]
    5. lift-sqrt.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    6. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \color{blue}{\sqrt{2}}\right)} \]
    7. associate-*r*N/A

      \[\leadsto \frac{1}{\left(t \cdot \mathsf{PI}\left(\right)\right) \cdot \color{blue}{\sqrt{2}}} \]
    8. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\color{blue}{2}}} \]
    9. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\color{blue}{2}}} \]
    10. lift-PI.f64N/A

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}} \]
    11. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \color{blue}{\sqrt{2}}} \]
    12. lift-sqrt.f6498.2

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}} \]
  6. Applied rewrites98.2%

    \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \color{blue}{\sqrt{2}}} \]
  7. Add Preprocessing

Alternative 6: 98.2% accurate, 3.4× speedup?

\[\begin{array}{l} \\ \frac{1}{\pi \cdot \left(t \cdot \sqrt{2}\right)} \end{array} \]
(FPCore (v t) :precision binary64 (/ 1.0 (* PI (* t (sqrt 2.0)))))
double code(double v, double t) {
	return 1.0 / (((double) M_PI) * (t * sqrt(2.0)));
}
public static double code(double v, double t) {
	return 1.0 / (Math.PI * (t * Math.sqrt(2.0)));
}
def code(v, t):
	return 1.0 / (math.pi * (t * math.sqrt(2.0)))
function code(v, t)
	return Float64(1.0 / Float64(pi * Float64(t * sqrt(2.0))))
end
function tmp = code(v, t)
	tmp = 1.0 / (pi * (t * sqrt(2.0)));
end
code[v_, t_] := N[(1.0 / N[(Pi * N[(t * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\pi \cdot \left(t \cdot \sqrt{2}\right)}
\end{array}
Derivation
  1. Initial program 99.3%

    \[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)} \]
  2. Taylor expanded in v around 0

    \[\leadsto \color{blue}{\frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{1}{\color{blue}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    3. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right) \cdot \color{blue}{t}} \]
    4. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    5. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    6. lower-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t} \]
    7. lift-PI.f6498.3

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t} \]
  4. Applied rewrites98.3%

    \[\leadsto \color{blue}{\frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot t}} \]
  5. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\sqrt{2} \cdot \pi\right) \cdot \color{blue}{t}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \color{blue}{\left(\sqrt{2} \cdot \pi\right)}} \]
    3. lift-PI.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)} \]
    5. lift-sqrt.f64N/A

      \[\leadsto \frac{1}{t \cdot \left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)} \]
    6. *-commutativeN/A

      \[\leadsto \frac{1}{t \cdot \left(\mathsf{PI}\left(\right) \cdot \color{blue}{\sqrt{2}}\right)} \]
    7. associate-*r*N/A

      \[\leadsto \frac{1}{\left(t \cdot \mathsf{PI}\left(\right)\right) \cdot \color{blue}{\sqrt{2}}} \]
    8. *-commutativeN/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\color{blue}{2}}} \]
    9. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\color{blue}{2}}} \]
    10. lift-PI.f64N/A

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}} \]
    11. lower-*.f64N/A

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \color{blue}{\sqrt{2}}} \]
    12. lift-sqrt.f6498.2

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \sqrt{2}} \]
  6. Applied rewrites98.2%

    \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \color{blue}{\sqrt{2}}} \]
  7. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\pi \cdot t\right) \cdot \color{blue}{\sqrt{2}}} \]
    2. lift-PI.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\color{blue}{2}}} \]
    4. lift-sqrt.f64N/A

      \[\leadsto \frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2}} \]
    5. associate-*l*N/A

      \[\leadsto \frac{1}{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(t \cdot \sqrt{2}\right)}} \]
    6. lower-*.f64N/A

      \[\leadsto \frac{1}{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(t \cdot \sqrt{2}\right)}} \]
    7. lift-PI.f64N/A

      \[\leadsto \frac{1}{\pi \cdot \left(\color{blue}{t} \cdot \sqrt{2}\right)} \]
    8. lower-*.f64N/A

      \[\leadsto \frac{1}{\pi \cdot \left(t \cdot \color{blue}{\sqrt{2}}\right)} \]
    9. lift-sqrt.f6498.2

      \[\leadsto \frac{1}{\pi \cdot \left(t \cdot \sqrt{2}\right)} \]
  8. Applied rewrites98.2%

    \[\leadsto \frac{1}{\pi \cdot \color{blue}{\left(t \cdot \sqrt{2}\right)}} \]
  9. Add Preprocessing

Reproduce

?
herbie shell --seed 2025117 
(FPCore (v t)
  :name "Falkner and Boettcher, Equation (20:1,3)"
  :precision binary64
  (/ (- 1.0 (* 5.0 (* v v))) (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))