
(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:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(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}
(FPCore (v) :precision binary64 (* (/ (sqrt (+ 2.0 (* 2.0 (* (* v v) -3.0)))) 4.0) (- 1.0 (* v v))))
double code(double v) {
return (sqrt((2.0 + (2.0 * ((v * v) * -3.0)))) / 4.0) * (1.0 - (v * v));
}
real(8) function code(v)
real(8), intent (in) :: v
code = (sqrt((2.0d0 + (2.0d0 * ((v * v) * (-3.0d0))))) / 4.0d0) * (1.0d0 - (v * v))
end function
public static double code(double v) {
return (Math.sqrt((2.0 + (2.0 * ((v * v) * -3.0)))) / 4.0) * (1.0 - (v * v));
}
def code(v): return (math.sqrt((2.0 + (2.0 * ((v * v) * -3.0)))) / 4.0) * (1.0 - (v * v))
function code(v) return Float64(Float64(sqrt(Float64(2.0 + Float64(2.0 * Float64(Float64(v * v) * -3.0)))) / 4.0) * Float64(1.0 - Float64(v * v))) end
function tmp = code(v) tmp = (sqrt((2.0 + (2.0 * ((v * v) * -3.0)))) / 4.0) * (1.0 - (v * v)); end
code[v_] := N[(N[(N[Sqrt[N[(2.0 + N[(2.0 * N[(N[(v * v), $MachinePrecision] * -3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / 4.0), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{2 + 2 \cdot \left(\left(v \cdot v\right) \cdot -3\right)}}{4} \cdot \left(1 - v \cdot v\right)
\end{array}
Initial program 100.0%
add-sqr-sqrt100.0%
sqrt-unprod100.0%
swap-sqr100.0%
metadata-eval100.0%
metadata-eval100.0%
swap-sqr100.0%
sqrt-unprod43.4%
add-sqr-sqrt97.2%
metadata-eval97.2%
distribute-lft-neg-in97.2%
add-log-exp97.2%
neg-log97.2%
add-sqr-sqrt97.2%
sqrt-unprod97.2%
swap-sqr97.2%
metadata-eval97.2%
metadata-eval97.2%
swap-sqr97.2%
sqrt-unprod43.4%
add-sqr-sqrt100.0%
exp-prod100.0%
pow2100.0%
Applied egg-rr100.0%
associate-*l/100.0%
pow1/2100.0%
pow1/2100.0%
pow-prod-down100.0%
pow-flip100.0%
log-pow100.0%
rem-log-exp100.0%
Applied egg-rr100.0%
unpow1/2100.0%
cancel-sign-sub100.0%
distribute-lft-in100.0%
metadata-eval100.0%
Simplified100.0%
pow2100.0%
Applied egg-rr100.0%
(FPCore (v) :precision binary64 (* (sqrt 2.0) (+ 0.25 (* (* v v) -0.625))))
double code(double v) {
return sqrt(2.0) * (0.25 + ((v * v) * -0.625));
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(2.0d0) * (0.25d0 + ((v * v) * (-0.625d0)))
end function
public static double code(double v) {
return Math.sqrt(2.0) * (0.25 + ((v * v) * -0.625));
}
def code(v): return math.sqrt(2.0) * (0.25 + ((v * v) * -0.625))
function code(v) return Float64(sqrt(2.0) * Float64(0.25 + Float64(Float64(v * v) * -0.625))) end
function tmp = code(v) tmp = sqrt(2.0) * (0.25 + ((v * v) * -0.625)); end
code[v_] := N[(N[Sqrt[2.0], $MachinePrecision] * N[(0.25 + N[(N[(v * v), $MachinePrecision] * -0.625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2} \cdot \left(0.25 + \left(v \cdot v\right) \cdot -0.625\right)
\end{array}
Initial program 100.0%
add-sqr-sqrt100.0%
sqrt-unprod100.0%
swap-sqr100.0%
metadata-eval100.0%
metadata-eval100.0%
swap-sqr100.0%
sqrt-unprod43.4%
add-sqr-sqrt97.2%
metadata-eval97.2%
distribute-lft-neg-in97.2%
add-log-exp97.2%
neg-log97.2%
add-sqr-sqrt97.2%
sqrt-unprod97.2%
swap-sqr97.2%
metadata-eval97.2%
metadata-eval97.2%
swap-sqr97.2%
sqrt-unprod43.4%
add-sqr-sqrt100.0%
exp-prod100.0%
pow2100.0%
Applied egg-rr100.0%
Taylor expanded in v around 0 98.7%
*-commutative98.7%
associate-*r*98.7%
*-commutative98.7%
distribute-rgt-out98.7%
associate-*l*98.7%
metadata-eval98.7%
metadata-eval98.7%
*-commutative98.7%
associate-*r*98.7%
*-commutative98.7%
associate-*r*98.7%
distribute-rgt-out98.7%
Simplified98.7%
pow2100.0%
Applied egg-rr98.7%
Final simplification98.7%
(FPCore (v) :precision binary64 (* (sqrt 2.0) 0.25))
double code(double v) {
return sqrt(2.0) * 0.25;
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(2.0d0) * 0.25d0
end function
public static double code(double v) {
return Math.sqrt(2.0) * 0.25;
}
def code(v): return math.sqrt(2.0) * 0.25
function code(v) return Float64(sqrt(2.0) * 0.25) end
function tmp = code(v) tmp = sqrt(2.0) * 0.25; end
code[v_] := N[(N[Sqrt[2.0], $MachinePrecision] * 0.25), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2} \cdot 0.25
\end{array}
Initial program 100.0%
add-sqr-sqrt100.0%
sqrt-unprod100.0%
swap-sqr100.0%
metadata-eval100.0%
metadata-eval100.0%
swap-sqr100.0%
sqrt-unprod43.4%
add-sqr-sqrt97.2%
metadata-eval97.2%
distribute-lft-neg-in97.2%
add-log-exp97.2%
neg-log97.2%
add-sqr-sqrt97.2%
sqrt-unprod97.2%
swap-sqr97.2%
metadata-eval97.2%
metadata-eval97.2%
swap-sqr97.2%
sqrt-unprod43.4%
add-sqr-sqrt100.0%
exp-prod100.0%
pow2100.0%
Applied egg-rr100.0%
Taylor expanded in v around 0 98.7%
*-commutative98.7%
associate-*r*98.7%
*-commutative98.7%
distribute-rgt-out98.7%
associate-*l*98.7%
metadata-eval98.7%
metadata-eval98.7%
*-commutative98.7%
associate-*r*98.7%
*-commutative98.7%
associate-*r*98.7%
distribute-rgt-out98.7%
Simplified98.7%
Taylor expanded in v around 0 97.2%
Final simplification97.2%
herbie shell --seed 2024108
(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))))