Falkner and Boettcher, Appendix B, 2

Percentage Accurate: 100.0% → 100.0%
Time: 10.2s
Alternatives: 5
Speedup: 1.0×

Specification

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

\\
\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right)
\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 5 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: 100.0% accurate, 1.0× speedup?

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

\\
\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right)
\end{array}

Alternative 1: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt{0.125 + {v}^{2} \cdot -0.375} \cdot \left(1 - v \cdot v\right) \end{array} \]
(FPCore (v)
 :precision binary64
 (* (sqrt (+ 0.125 (* (pow v 2.0) -0.375))) (- 1.0 (* v v))))
double code(double v) {
	return sqrt((0.125 + (pow(v, 2.0) * -0.375))) * (1.0 - (v * v));
}
real(8) function code(v)
    real(8), intent (in) :: v
    code = sqrt((0.125d0 + ((v ** 2.0d0) * (-0.375d0)))) * (1.0d0 - (v * v))
end function
public static double code(double v) {
	return Math.sqrt((0.125 + (Math.pow(v, 2.0) * -0.375))) * (1.0 - (v * v));
}
def code(v):
	return math.sqrt((0.125 + (math.pow(v, 2.0) * -0.375))) * (1.0 - (v * v))
function code(v)
	return Float64(sqrt(Float64(0.125 + Float64((v ^ 2.0) * -0.375))) * Float64(1.0 - Float64(v * v)))
end
function tmp = code(v)
	tmp = sqrt((0.125 + ((v ^ 2.0) * -0.375))) * (1.0 - (v * v));
end
code[v_] := N[(N[Sqrt[N[(0.125 + N[(N[Power[v, 2.0], $MachinePrecision] * -0.375), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{0.125 + {v}^{2} \cdot -0.375} \cdot \left(1 - v \cdot v\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-sqr-sqrt100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{3 \cdot \left(v \cdot v\right)} \cdot \sqrt{3 \cdot \left(v \cdot v\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    2. sqrt-unprod100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{\left(3 \cdot \left(v \cdot v\right)\right) \cdot \left(3 \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    3. swap-sqr100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(3 \cdot 3\right) \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    4. metadata-eval100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{9} \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    5. metadata-eval100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(-3 \cdot -3\right)} \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    6. swap-sqr100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(-3 \cdot \left(v \cdot v\right)\right) \cdot \left(-3 \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    7. sqrt-unprod48.4%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{-3 \cdot \left(v \cdot v\right)} \cdot \sqrt{-3 \cdot \left(v \cdot v\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    8. expm1-log1p-u48.4%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{-3 \cdot \left(v \cdot v\right)} \cdot \sqrt{-3 \cdot \left(v \cdot v\right)}\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    9. add-sqr-sqrt98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\mathsf{log1p}\left(\color{blue}{-3 \cdot \left(v \cdot v\right)}\right)\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    10. log1p-define98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + -3 \cdot \left(v \cdot v\right)\right)}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    11. metadata-eval98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\log \left(1 + \color{blue}{\left(-3\right)} \cdot \left(v \cdot v\right)\right)\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    12. cancel-sign-sub-inv98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\log \color{blue}{\left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    13. expm1-undefine98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\left(e^{\log \left(1 - 3 \cdot \left(v \cdot v\right)\right)} - 1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    14. add-exp-log98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \left(\color{blue}{\left(1 - 3 \cdot \left(v \cdot v\right)\right)} - 1\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    15. add-cube-cbrt98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \left(\color{blue}{\left(\sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)} \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}} - 1\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    16. fma-neg98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{fma}\left(\sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)} \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}, \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}, -1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
  4. Applied egg-rr100.0%

    \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{fma}\left({\left(\sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}\right)}^{2}, \sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}, -1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
  5. Step-by-step derivation
    1. pow1100.0%

      \[\leadsto \color{blue}{{\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{fma}\left({\left(\sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}\right)}^{2}, \sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}, -1\right)}\right)}^{1}} \cdot \left(1 - v \cdot v\right) \]
  6. Applied egg-rr100.0%

    \[\leadsto \color{blue}{{\left(\sqrt{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}\right)}^{1}} \cdot \left(1 - v \cdot v\right) \]
  7. Step-by-step derivation
    1. unpow1100.0%

      \[\leadsto \color{blue}{\sqrt{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}} \cdot \left(1 - v \cdot v\right) \]
    2. *-commutative100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot \left(1 - \left(3 \cdot {v}^{2} + 0\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    3. sub-neg100.0%

      \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + \left(-\left(3 \cdot {v}^{2} + 0\right)\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    4. distribute-lft-in100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot 1 + 0.125 \cdot \left(-\left(3 \cdot {v}^{2} + 0\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    5. metadata-eval100.0%

      \[\leadsto \sqrt{\color{blue}{0.125} + 0.125 \cdot \left(-\left(3 \cdot {v}^{2} + 0\right)\right)} \cdot \left(1 - v \cdot v\right) \]
    6. +-rgt-identity100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left(-\color{blue}{3 \cdot {v}^{2}}\right)} \cdot \left(1 - v \cdot v\right) \]
    7. *-commutative100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left(-\color{blue}{{v}^{2} \cdot 3}\right)} \cdot \left(1 - v \cdot v\right) \]
    8. distribute-rgt-neg-in100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \color{blue}{\left({v}^{2} \cdot \left(-3\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    9. metadata-eval100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left({v}^{2} \cdot \color{blue}{-3}\right)} \cdot \left(1 - v \cdot v\right) \]
  8. Simplified100.0%

    \[\leadsto \color{blue}{\sqrt{0.125 + 0.125 \cdot \left({v}^{2} \cdot -3\right)}} \cdot \left(1 - v \cdot v\right) \]
  9. Step-by-step derivation
    1. metadata-eval100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot 1} + 0.125 \cdot \left({v}^{2} \cdot -3\right)} \cdot \left(1 - v \cdot v\right) \]
    2. distribute-lft-in100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot \left(1 + {v}^{2} \cdot -3\right)}} \cdot \left(1 - v \cdot v\right) \]
    3. *-commutative100.0%

      \[\leadsto \sqrt{0.125 \cdot \left(1 + \color{blue}{-3 \cdot {v}^{2}}\right)} \cdot \left(1 - v \cdot v\right) \]
    4. metadata-eval100.0%

      \[\leadsto \sqrt{0.125 \cdot \left(1 + \color{blue}{\left(-3\right)} \cdot {v}^{2}\right)} \cdot \left(1 - v \cdot v\right) \]
    5. cancel-sign-sub-inv100.0%

      \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 - 3 \cdot {v}^{2}\right)}} \cdot \left(1 - v \cdot v\right) \]
    6. +-rgt-identity100.0%

      \[\leadsto \sqrt{0.125 \cdot \left(1 - \color{blue}{\left(3 \cdot {v}^{2} + 0\right)}\right)} \cdot \left(1 - v \cdot v\right) \]
    7. *-commutative100.0%

      \[\leadsto \sqrt{\color{blue}{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}} \cdot \left(1 - v \cdot v\right) \]
    8. *-un-lft-identity100.0%

      \[\leadsto \color{blue}{\left(1 \cdot \sqrt{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}\right)} \cdot \left(1 - v \cdot v\right) \]
    9. *-commutative100.0%

      \[\leadsto \left(1 \cdot \sqrt{\color{blue}{0.125 \cdot \left(1 - \left(3 \cdot {v}^{2} + 0\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    10. +-rgt-identity100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 \cdot \left(1 - \color{blue}{3 \cdot {v}^{2}}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    11. cancel-sign-sub-inv100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 \cdot \color{blue}{\left(1 + \left(-3\right) \cdot {v}^{2}\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    12. metadata-eval100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 \cdot \left(1 + \color{blue}{-3} \cdot {v}^{2}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    13. *-commutative100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 \cdot \left(1 + \color{blue}{{v}^{2} \cdot -3}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    14. distribute-rgt-in100.0%

      \[\leadsto \left(1 \cdot \sqrt{\color{blue}{1 \cdot 0.125 + \left({v}^{2} \cdot -3\right) \cdot 0.125}}\right) \cdot \left(1 - v \cdot v\right) \]
    15. metadata-eval100.0%

      \[\leadsto \left(1 \cdot \sqrt{\color{blue}{0.125} + \left({v}^{2} \cdot -3\right) \cdot 0.125}\right) \cdot \left(1 - v \cdot v\right) \]
    16. associate-*l*100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 + \color{blue}{{v}^{2} \cdot \left(-3 \cdot 0.125\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    17. metadata-eval100.0%

      \[\leadsto \left(1 \cdot \sqrt{0.125 + {v}^{2} \cdot \color{blue}{-0.375}}\right) \cdot \left(1 - v \cdot v\right) \]
  10. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\left(1 \cdot \sqrt{0.125 + {v}^{2} \cdot -0.375}\right)} \cdot \left(1 - v \cdot v\right) \]
  11. Step-by-step derivation
    1. *-lft-identity100.0%

      \[\leadsto \color{blue}{\sqrt{0.125 + {v}^{2} \cdot -0.375}} \cdot \left(1 - v \cdot v\right) \]
  12. Simplified100.0%

    \[\leadsto \color{blue}{\sqrt{0.125 + {v}^{2} \cdot -0.375}} \cdot \left(1 - v \cdot v\right) \]
  13. Final simplification100.0%

    \[\leadsto \sqrt{0.125 + {v}^{2} \cdot -0.375} \cdot \left(1 - v \cdot v\right) \]
  14. Add Preprocessing

Alternative 2: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt{2} \cdot \left(0.25 + {v}^{2} \cdot -0.625\right) \end{array} \]
(FPCore (v) :precision binary64 (* (sqrt 2.0) (+ 0.25 (* (pow v 2.0) -0.625))))
double code(double v) {
	return sqrt(2.0) * (0.25 + (pow(v, 2.0) * -0.625));
}
real(8) function code(v)
    real(8), intent (in) :: v
    code = sqrt(2.0d0) * (0.25d0 + ((v ** 2.0d0) * (-0.625d0)))
end function
public static double code(double v) {
	return Math.sqrt(2.0) * (0.25 + (Math.pow(v, 2.0) * -0.625));
}
def code(v):
	return math.sqrt(2.0) * (0.25 + (math.pow(v, 2.0) * -0.625))
function code(v)
	return Float64(sqrt(2.0) * Float64(0.25 + Float64((v ^ 2.0) * -0.625)))
end
function tmp = code(v)
	tmp = sqrt(2.0) * (0.25 + ((v ^ 2.0) * -0.625));
end
code[v_] := N[(N[Sqrt[2.0], $MachinePrecision] * N[(0.25 + N[(N[Power[v, 2.0], $MachinePrecision] * -0.625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{2} \cdot \left(0.25 + {v}^{2} \cdot -0.625\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right) \]
  2. Step-by-step derivation
    1. associate-*l*100.0%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
    2. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \color{blue}{\left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    3. cancel-sign-sub-inv100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{\color{blue}{1 + \left(-3\right) \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    4. metadata-eval100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + \color{blue}{-3} \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \]
    5. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \color{blue}{\left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in v around 0 99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + -2.5 \cdot {v}^{2}\right)} \]
  6. Step-by-step derivation
    1. *-commutative99.3%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(1 + \color{blue}{{v}^{2} \cdot -2.5}\right) \]
  7. Simplified99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + {v}^{2} \cdot -2.5\right)} \]
  8. Taylor expanded in v around 0 99.3%

    \[\leadsto \color{blue}{-0.625 \cdot \left({v}^{2} \cdot \sqrt{2}\right) + 0.25 \cdot \sqrt{2}} \]
  9. Step-by-step derivation
    1. +-commutative99.3%

      \[\leadsto \color{blue}{0.25 \cdot \sqrt{2} + -0.625 \cdot \left({v}^{2} \cdot \sqrt{2}\right)} \]
    2. associate-*r*99.3%

      \[\leadsto 0.25 \cdot \sqrt{2} + \color{blue}{\left(-0.625 \cdot {v}^{2}\right) \cdot \sqrt{2}} \]
    3. distribute-rgt-out99.3%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \left(0.25 + -0.625 \cdot {v}^{2}\right)} \]
    4. *-commutative99.3%

      \[\leadsto \sqrt{2} \cdot \left(0.25 + \color{blue}{{v}^{2} \cdot -0.625}\right) \]
  10. Simplified99.3%

    \[\leadsto \color{blue}{\sqrt{2} \cdot \left(0.25 + {v}^{2} \cdot -0.625\right)} \]
  11. Final simplification99.3%

    \[\leadsto \sqrt{2} \cdot \left(0.25 + {v}^{2} \cdot -0.625\right) \]
  12. Add Preprocessing

Alternative 3: 99.5% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \sqrt{0.125 + {v}^{2} \cdot -0.625} \end{array} \]
(FPCore (v) :precision binary64 (sqrt (+ 0.125 (* (pow v 2.0) -0.625))))
double code(double v) {
	return sqrt((0.125 + (pow(v, 2.0) * -0.625)));
}
real(8) function code(v)
    real(8), intent (in) :: v
    code = sqrt((0.125d0 + ((v ** 2.0d0) * (-0.625d0))))
end function
public static double code(double v) {
	return Math.sqrt((0.125 + (Math.pow(v, 2.0) * -0.625)));
}
def code(v):
	return math.sqrt((0.125 + (math.pow(v, 2.0) * -0.625)))
function code(v)
	return sqrt(Float64(0.125 + Float64((v ^ 2.0) * -0.625)))
end
function tmp = code(v)
	tmp = sqrt((0.125 + ((v ^ 2.0) * -0.625)));
end
code[v_] := N[Sqrt[N[(0.125 + N[(N[Power[v, 2.0], $MachinePrecision] * -0.625), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{0.125 + {v}^{2} \cdot -0.625}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right) \]
  2. Step-by-step derivation
    1. associate-*l*100.0%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
    2. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \color{blue}{\left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    3. cancel-sign-sub-inv100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{\color{blue}{1 + \left(-3\right) \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    4. metadata-eval100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + \color{blue}{-3} \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \]
    5. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \color{blue}{\left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in v around 0 99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + -2.5 \cdot {v}^{2}\right)} \]
  6. Step-by-step derivation
    1. *-commutative99.3%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(1 + \color{blue}{{v}^{2} \cdot -2.5}\right) \]
  7. Simplified99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + {v}^{2} \cdot -2.5\right)} \]
  8. Step-by-step derivation
    1. add-sqr-sqrt97.8%

      \[\leadsto \color{blue}{\sqrt{\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)} \cdot \sqrt{\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)}} \]
    2. sqrt-unprod99.3%

      \[\leadsto \color{blue}{\sqrt{\left(\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right) \cdot \left(\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)}} \]
    3. swap-sqr99.3%

      \[\leadsto \sqrt{\color{blue}{\left(\frac{\sqrt{2}}{4} \cdot \frac{\sqrt{2}}{4}\right) \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)}} \]
    4. frac-times99.3%

      \[\leadsto \sqrt{\color{blue}{\frac{\sqrt{2} \cdot \sqrt{2}}{4 \cdot 4}} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    5. rem-square-sqrt99.3%

      \[\leadsto \sqrt{\frac{\color{blue}{2}}{4 \cdot 4} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    6. metadata-eval99.3%

      \[\leadsto \sqrt{\frac{2}{\color{blue}{16}} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    7. metadata-eval99.3%

      \[\leadsto \sqrt{\color{blue}{0.125} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    8. pow299.3%

      \[\leadsto \sqrt{0.125 \cdot \color{blue}{{\left(1 + {v}^{2} \cdot -2.5\right)}^{2}}} \]
    9. +-commutative99.3%

      \[\leadsto \sqrt{0.125 \cdot {\color{blue}{\left({v}^{2} \cdot -2.5 + 1\right)}}^{2}} \]
    10. fma-define99.3%

      \[\leadsto \sqrt{0.125 \cdot {\color{blue}{\left(\mathsf{fma}\left({v}^{2}, -2.5, 1\right)\right)}}^{2}} \]
  9. Applied egg-rr99.3%

    \[\leadsto \color{blue}{\sqrt{0.125 \cdot {\left(\mathsf{fma}\left({v}^{2}, -2.5, 1\right)\right)}^{2}}} \]
  10. Taylor expanded in v around 0 99.2%

    \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + -5 \cdot {v}^{2}\right)}} \]
  11. Step-by-step derivation
    1. *-commutative99.2%

      \[\leadsto \sqrt{0.125 \cdot \left(1 + \color{blue}{{v}^{2} \cdot -5}\right)} \]
  12. Simplified99.2%

    \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + {v}^{2} \cdot -5\right)}} \]
  13. Step-by-step derivation
    1. *-un-lft-identity99.2%

      \[\leadsto \color{blue}{1 \cdot \sqrt{0.125 \cdot \left(1 + {v}^{2} \cdot -5\right)}} \]
    2. distribute-rgt-in99.2%

      \[\leadsto 1 \cdot \sqrt{\color{blue}{1 \cdot 0.125 + \left({v}^{2} \cdot -5\right) \cdot 0.125}} \]
    3. metadata-eval99.2%

      \[\leadsto 1 \cdot \sqrt{\color{blue}{0.125} + \left({v}^{2} \cdot -5\right) \cdot 0.125} \]
    4. associate-*l*99.2%

      \[\leadsto 1 \cdot \sqrt{0.125 + \color{blue}{{v}^{2} \cdot \left(-5 \cdot 0.125\right)}} \]
    5. metadata-eval99.2%

      \[\leadsto 1 \cdot \sqrt{0.125 + {v}^{2} \cdot \color{blue}{-0.625}} \]
  14. Applied egg-rr99.2%

    \[\leadsto \color{blue}{1 \cdot \sqrt{0.125 + {v}^{2} \cdot -0.625}} \]
  15. Step-by-step derivation
    1. *-lft-identity99.2%

      \[\leadsto \color{blue}{\sqrt{0.125 + {v}^{2} \cdot -0.625}} \]
  16. Simplified99.2%

    \[\leadsto \color{blue}{\sqrt{0.125 + {v}^{2} \cdot -0.625}} \]
  17. Final simplification99.2%

    \[\leadsto \sqrt{0.125 + {v}^{2} \cdot -0.625} \]
  18. Add Preprocessing

Alternative 4: 99.0% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \left(1 - v \cdot v\right) \cdot \sqrt{0.125} \end{array} \]
(FPCore (v) :precision binary64 (* (- 1.0 (* v v)) (sqrt 0.125)))
double code(double v) {
	return (1.0 - (v * v)) * sqrt(0.125);
}
real(8) function code(v)
    real(8), intent (in) :: v
    code = (1.0d0 - (v * v)) * sqrt(0.125d0)
end function
public static double code(double v) {
	return (1.0 - (v * v)) * Math.sqrt(0.125);
}
def code(v):
	return (1.0 - (v * v)) * math.sqrt(0.125)
function code(v)
	return Float64(Float64(1.0 - Float64(v * v)) * sqrt(0.125))
end
function tmp = code(v)
	tmp = (1.0 - (v * v)) * sqrt(0.125);
end
code[v_] := N[(N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision] * N[Sqrt[0.125], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(1 - v \cdot v\right) \cdot \sqrt{0.125}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. add-sqr-sqrt100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{3 \cdot \left(v \cdot v\right)} \cdot \sqrt{3 \cdot \left(v \cdot v\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    2. sqrt-unprod100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{\left(3 \cdot \left(v \cdot v\right)\right) \cdot \left(3 \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    3. swap-sqr100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(3 \cdot 3\right) \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    4. metadata-eval100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{9} \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    5. metadata-eval100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(-3 \cdot -3\right)} \cdot \left(\left(v \cdot v\right) \cdot \left(v \cdot v\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    6. swap-sqr100.0%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \sqrt{\color{blue}{\left(-3 \cdot \left(v \cdot v\right)\right) \cdot \left(-3 \cdot \left(v \cdot v\right)\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    7. sqrt-unprod48.4%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\sqrt{-3 \cdot \left(v \cdot v\right)} \cdot \sqrt{-3 \cdot \left(v \cdot v\right)}}}\right) \cdot \left(1 - v \cdot v\right) \]
    8. expm1-log1p-u48.4%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{-3 \cdot \left(v \cdot v\right)} \cdot \sqrt{-3 \cdot \left(v \cdot v\right)}\right)\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    9. add-sqr-sqrt98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\mathsf{log1p}\left(\color{blue}{-3 \cdot \left(v \cdot v\right)}\right)\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    10. log1p-define98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + -3 \cdot \left(v \cdot v\right)\right)}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    11. metadata-eval98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\log \left(1 + \color{blue}{\left(-3\right)} \cdot \left(v \cdot v\right)\right)\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    12. cancel-sign-sub-inv98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{expm1}\left(\log \color{blue}{\left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    13. expm1-undefine98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\left(e^{\log \left(1 - 3 \cdot \left(v \cdot v\right)\right)} - 1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
    14. add-exp-log98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \left(\color{blue}{\left(1 - 3 \cdot \left(v \cdot v\right)\right)} - 1\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    15. add-cube-cbrt98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \left(\color{blue}{\left(\sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)} \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}} - 1\right)}\right) \cdot \left(1 - v \cdot v\right) \]
    16. fma-neg98.7%

      \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{fma}\left(\sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)} \cdot \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}, \sqrt[3]{1 - 3 \cdot \left(v \cdot v\right)}, -1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
  4. Applied egg-rr100.0%

    \[\leadsto \left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \color{blue}{\mathsf{fma}\left({\left(\sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}\right)}^{2}, \sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}, -1\right)}}\right) \cdot \left(1 - v \cdot v\right) \]
  5. Step-by-step derivation
    1. pow1100.0%

      \[\leadsto \color{blue}{{\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - \mathsf{fma}\left({\left(\sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}\right)}^{2}, \sqrt[3]{\mathsf{fma}\left(3, {v}^{2}, 1\right)}, -1\right)}\right)}^{1}} \cdot \left(1 - v \cdot v\right) \]
  6. Applied egg-rr100.0%

    \[\leadsto \color{blue}{{\left(\sqrt{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}\right)}^{1}} \cdot \left(1 - v \cdot v\right) \]
  7. Step-by-step derivation
    1. unpow1100.0%

      \[\leadsto \color{blue}{\sqrt{\left(1 - \left(3 \cdot {v}^{2} + 0\right)\right) \cdot 0.125}} \cdot \left(1 - v \cdot v\right) \]
    2. *-commutative100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot \left(1 - \left(3 \cdot {v}^{2} + 0\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    3. sub-neg100.0%

      \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + \left(-\left(3 \cdot {v}^{2} + 0\right)\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    4. distribute-lft-in100.0%

      \[\leadsto \sqrt{\color{blue}{0.125 \cdot 1 + 0.125 \cdot \left(-\left(3 \cdot {v}^{2} + 0\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    5. metadata-eval100.0%

      \[\leadsto \sqrt{\color{blue}{0.125} + 0.125 \cdot \left(-\left(3 \cdot {v}^{2} + 0\right)\right)} \cdot \left(1 - v \cdot v\right) \]
    6. +-rgt-identity100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left(-\color{blue}{3 \cdot {v}^{2}}\right)} \cdot \left(1 - v \cdot v\right) \]
    7. *-commutative100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left(-\color{blue}{{v}^{2} \cdot 3}\right)} \cdot \left(1 - v \cdot v\right) \]
    8. distribute-rgt-neg-in100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \color{blue}{\left({v}^{2} \cdot \left(-3\right)\right)}} \cdot \left(1 - v \cdot v\right) \]
    9. metadata-eval100.0%

      \[\leadsto \sqrt{0.125 + 0.125 \cdot \left({v}^{2} \cdot \color{blue}{-3}\right)} \cdot \left(1 - v \cdot v\right) \]
  8. Simplified100.0%

    \[\leadsto \color{blue}{\sqrt{0.125 + 0.125 \cdot \left({v}^{2} \cdot -3\right)}} \cdot \left(1 - v \cdot v\right) \]
  9. Taylor expanded in v around 0 98.7%

    \[\leadsto \color{blue}{\sqrt{0.125}} \cdot \left(1 - v \cdot v\right) \]
  10. Final simplification98.7%

    \[\leadsto \left(1 - v \cdot v\right) \cdot \sqrt{0.125} \]
  11. Add Preprocessing

Alternative 5: 98.9% accurate, 2.1× speedup?

\[\begin{array}{l} \\ \sqrt{0.125} \end{array} \]
(FPCore (v) :precision binary64 (sqrt 0.125))
double code(double v) {
	return sqrt(0.125);
}
real(8) function code(v)
    real(8), intent (in) :: v
    code = sqrt(0.125d0)
end function
public static double code(double v) {
	return Math.sqrt(0.125);
}
def code(v):
	return math.sqrt(0.125)
function code(v)
	return sqrt(0.125)
end
function tmp = code(v)
	tmp = sqrt(0.125);
end
code[v_] := N[Sqrt[0.125], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{0.125}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(\frac{\sqrt{2}}{4} \cdot \sqrt{1 - 3 \cdot \left(v \cdot v\right)}\right) \cdot \left(1 - v \cdot v\right) \]
  2. Step-by-step derivation
    1. associate-*l*100.0%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
    2. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 - 3 \cdot \color{blue}{\left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    3. cancel-sign-sub-inv100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{\color{blue}{1 + \left(-3\right) \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
    4. metadata-eval100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + \color{blue}{-3} \cdot \left(\left(-v\right) \cdot \left(-v\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \]
    5. sqr-neg100.0%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \color{blue}{\left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{4} \cdot \left(\sqrt{1 + -3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in v around 0 99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + -2.5 \cdot {v}^{2}\right)} \]
  6. Step-by-step derivation
    1. *-commutative99.3%

      \[\leadsto \frac{\sqrt{2}}{4} \cdot \left(1 + \color{blue}{{v}^{2} \cdot -2.5}\right) \]
  7. Simplified99.3%

    \[\leadsto \frac{\sqrt{2}}{4} \cdot \color{blue}{\left(1 + {v}^{2} \cdot -2.5\right)} \]
  8. Step-by-step derivation
    1. add-sqr-sqrt97.8%

      \[\leadsto \color{blue}{\sqrt{\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)} \cdot \sqrt{\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)}} \]
    2. sqrt-unprod99.3%

      \[\leadsto \color{blue}{\sqrt{\left(\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right) \cdot \left(\frac{\sqrt{2}}{4} \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)}} \]
    3. swap-sqr99.3%

      \[\leadsto \sqrt{\color{blue}{\left(\frac{\sqrt{2}}{4} \cdot \frac{\sqrt{2}}{4}\right) \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)}} \]
    4. frac-times99.3%

      \[\leadsto \sqrt{\color{blue}{\frac{\sqrt{2} \cdot \sqrt{2}}{4 \cdot 4}} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    5. rem-square-sqrt99.3%

      \[\leadsto \sqrt{\frac{\color{blue}{2}}{4 \cdot 4} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    6. metadata-eval99.3%

      \[\leadsto \sqrt{\frac{2}{\color{blue}{16}} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    7. metadata-eval99.3%

      \[\leadsto \sqrt{\color{blue}{0.125} \cdot \left(\left(1 + {v}^{2} \cdot -2.5\right) \cdot \left(1 + {v}^{2} \cdot -2.5\right)\right)} \]
    8. pow299.3%

      \[\leadsto \sqrt{0.125 \cdot \color{blue}{{\left(1 + {v}^{2} \cdot -2.5\right)}^{2}}} \]
    9. +-commutative99.3%

      \[\leadsto \sqrt{0.125 \cdot {\color{blue}{\left({v}^{2} \cdot -2.5 + 1\right)}}^{2}} \]
    10. fma-define99.3%

      \[\leadsto \sqrt{0.125 \cdot {\color{blue}{\left(\mathsf{fma}\left({v}^{2}, -2.5, 1\right)\right)}}^{2}} \]
  9. Applied egg-rr99.3%

    \[\leadsto \color{blue}{\sqrt{0.125 \cdot {\left(\mathsf{fma}\left({v}^{2}, -2.5, 1\right)\right)}^{2}}} \]
  10. Taylor expanded in v around 0 99.2%

    \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + -5 \cdot {v}^{2}\right)}} \]
  11. Step-by-step derivation
    1. *-commutative99.2%

      \[\leadsto \sqrt{0.125 \cdot \left(1 + \color{blue}{{v}^{2} \cdot -5}\right)} \]
  12. Simplified99.2%

    \[\leadsto \sqrt{0.125 \cdot \color{blue}{\left(1 + {v}^{2} \cdot -5\right)}} \]
  13. Taylor expanded in v around 0 98.7%

    \[\leadsto \color{blue}{\sqrt{0.125}} \]
  14. Final simplification98.7%

    \[\leadsto \sqrt{0.125} \]
  15. Add Preprocessing

Reproduce

?
herbie shell --seed 2024067 
(FPCore (v)
  :name "Falkner and Boettcher, Appendix B, 2"
  :precision binary64
  (* (* (/ (sqrt 2.0) 4.0) (sqrt (- 1.0 (* 3.0 (* v v))))) (- 1.0 (* v v))))