
(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 4 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) 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}
Initial program 100.0%
(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}
Initial program 100.0%
associate-*l*100.0%
sqr-neg100.0%
cancel-sign-sub-inv100.0%
metadata-eval100.0%
sqr-neg100.0%
Simplified100.0%
flip-+100.0%
sqrt-div100.0%
metadata-eval100.0%
*-commutative100.0%
*-commutative100.0%
swap-sqr100.0%
pow2100.0%
pow2100.0%
pow-prod-up100.0%
metadata-eval100.0%
metadata-eval100.0%
cancel-sign-sub-inv100.0%
metadata-eval100.0%
pow2100.0%
Applied egg-rr100.0%
*-commutative100.0%
Simplified100.0%
Taylor expanded in v around 0 99.5%
*-commutative99.5%
associate-*r*99.5%
*-commutative99.5%
*-commutative99.5%
distribute-rgt-out99.5%
metadata-eval99.5%
associate-*l*99.5%
metadata-eval99.5%
associate-*r*99.5%
*-commutative99.5%
associate-*r*99.5%
distribute-rgt-out99.5%
*-commutative99.5%
Simplified99.5%
(FPCore (v) :precision binary64 (* (/ (sqrt 2.0) 4.0) (- 1.0 (* v v))))
double code(double v) {
return (sqrt(2.0) / 4.0) * (1.0 - (v * v));
}
real(8) function code(v)
real(8), intent (in) :: v
code = (sqrt(2.0d0) / 4.0d0) * (1.0d0 - (v * v))
end function
public static double code(double v) {
return (Math.sqrt(2.0) / 4.0) * (1.0 - (v * v));
}
def code(v): return (math.sqrt(2.0) / 4.0) * (1.0 - (v * v))
function code(v) return Float64(Float64(sqrt(2.0) / 4.0) * Float64(1.0 - Float64(v * v))) end
function tmp = code(v) tmp = (sqrt(2.0) / 4.0) * (1.0 - (v * v)); end
code[v_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] / 4.0), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{2}}{4} \cdot \left(1 - v \cdot v\right)
\end{array}
Initial program 100.0%
associate-*l*100.0%
sqr-neg100.0%
cancel-sign-sub-inv100.0%
metadata-eval100.0%
sqr-neg100.0%
Simplified100.0%
Taylor expanded in v around 0 99.1%
Final simplification99.1%
(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}
Initial program 100.0%
associate-*l*100.0%
sqr-neg100.0%
cancel-sign-sub-inv100.0%
metadata-eval100.0%
sqr-neg100.0%
Simplified100.0%
Taylor expanded in v around 0 99.1%
add-sqr-sqrt97.5%
pow297.5%
add-sqr-sqrt97.5%
sqrt-unprod97.5%
frac-times97.5%
rem-square-sqrt97.5%
metadata-eval97.5%
metadata-eval97.5%
*-lft-identity97.5%
pow297.5%
Applied egg-rr97.5%
Taylor expanded in v around 0 99.0%
herbie shell --seed 2024107
(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))))