
(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 6 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 (* (/ 1.0 (/ 4.0 (sqrt (+ 2.0 (* v (* v -6.0)))))) (- 1.0 (* v v))))
double code(double v) {
return (1.0 / (4.0 / sqrt((2.0 + (v * (v * -6.0)))))) * (1.0 - (v * v));
}
real(8) function code(v)
real(8), intent (in) :: v
code = (1.0d0 / (4.0d0 / sqrt((2.0d0 + (v * (v * (-6.0d0))))))) * (1.0d0 - (v * v))
end function
public static double code(double v) {
return (1.0 / (4.0 / Math.sqrt((2.0 + (v * (v * -6.0)))))) * (1.0 - (v * v));
}
def code(v): return (1.0 / (4.0 / math.sqrt((2.0 + (v * (v * -6.0)))))) * (1.0 - (v * v))
function code(v) return Float64(Float64(1.0 / Float64(4.0 / sqrt(Float64(2.0 + Float64(v * Float64(v * -6.0)))))) * Float64(1.0 - Float64(v * v))) end
function tmp = code(v) tmp = (1.0 / (4.0 / sqrt((2.0 + (v * (v * -6.0)))))) * (1.0 - (v * v)); end
code[v_] := N[(N[(1.0 / N[(4.0 / N[Sqrt[N[(2.0 + N[(v * N[(v * -6.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{4}{\sqrt{2 + v \cdot \left(v \cdot -6\right)}}} \cdot \left(1 - v \cdot v\right)
\end{array}
Initial program 100.0%
associate-*r*100.0%
Simplified100.0%
associate-*l/100.0%
clear-num100.0%
sqrt-unprod100.0%
sub-neg100.0%
+-commutative100.0%
*-commutative100.0%
distribute-rgt-neg-in100.0%
distribute-lft-neg-in100.0%
metadata-eval100.0%
*-commutative100.0%
fma-udef100.0%
Applied egg-rr100.0%
fma-udef100.0%
Applied egg-rr100.0%
expm1-log1p-u100.0%
expm1-udef100.0%
+-commutative100.0%
distribute-rgt-in100.0%
metadata-eval100.0%
associate-*r*100.0%
associate-*l*100.0%
metadata-eval100.0%
Applied egg-rr100.0%
expm1-def100.0%
expm1-log1p100.0%
associate-*l*100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (* (- 1.0 (* v v)) (sqrt (* (+ 1.0 (* v (* v -3.0))) 0.125))))
double code(double v) {
return (1.0 - (v * v)) * sqrt(((1.0 + (v * (v * -3.0))) * 0.125));
}
real(8) function code(v)
real(8), intent (in) :: v
code = (1.0d0 - (v * v)) * sqrt(((1.0d0 + (v * (v * (-3.0d0)))) * 0.125d0))
end function
public static double code(double v) {
return (1.0 - (v * v)) * Math.sqrt(((1.0 + (v * (v * -3.0))) * 0.125));
}
def code(v): return (1.0 - (v * v)) * math.sqrt(((1.0 + (v * (v * -3.0))) * 0.125))
function code(v) return Float64(Float64(1.0 - Float64(v * v)) * sqrt(Float64(Float64(1.0 + Float64(v * Float64(v * -3.0))) * 0.125))) end
function tmp = code(v) tmp = (1.0 - (v * v)) * sqrt(((1.0 + (v * (v * -3.0))) * 0.125)); end
code[v_] := N[(N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(N[(1.0 + N[(v * N[(v * -3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 0.125), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(1 - v \cdot v\right) \cdot \sqrt{\left(1 + v \cdot \left(v \cdot -3\right)\right) \cdot 0.125}
\end{array}
Initial program 100.0%
associate-*r*100.0%
Simplified100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
*-commutative100.0%
*-commutative100.0%
swap-sqr100.0%
add-sqr-sqrt100.0%
sub-neg100.0%
+-commutative100.0%
*-commutative100.0%
distribute-rgt-neg-in100.0%
distribute-lft-neg-in100.0%
metadata-eval100.0%
*-commutative100.0%
fma-udef100.0%
frac-times100.0%
Applied egg-rr100.0%
fma-udef100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (* (- 1.0 (* v v)) (sqrt (+ 0.125 (* (* v v) -0.375)))))
double code(double v) {
return (1.0 - (v * v)) * sqrt((0.125 + ((v * v) * -0.375)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = (1.0d0 - (v * v)) * sqrt((0.125d0 + ((v * v) * (-0.375d0))))
end function
public static double code(double v) {
return (1.0 - (v * v)) * Math.sqrt((0.125 + ((v * v) * -0.375)));
}
def code(v): return (1.0 - (v * v)) * math.sqrt((0.125 + ((v * v) * -0.375)))
function code(v) return Float64(Float64(1.0 - Float64(v * v)) * sqrt(Float64(0.125 + Float64(Float64(v * v) * -0.375)))) end
function tmp = code(v) tmp = (1.0 - (v * v)) * sqrt((0.125 + ((v * v) * -0.375))); end
code[v_] := N[(N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(0.125 + N[(N[(v * v), $MachinePrecision] * -0.375), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(1 - v \cdot v\right) \cdot \sqrt{0.125 + \left(v \cdot v\right) \cdot -0.375}
\end{array}
Initial program 100.0%
associate-*r*100.0%
Simplified100.0%
associate-*l/100.0%
clear-num100.0%
sqrt-unprod100.0%
sub-neg100.0%
+-commutative100.0%
*-commutative100.0%
distribute-rgt-neg-in100.0%
distribute-lft-neg-in100.0%
metadata-eval100.0%
*-commutative100.0%
fma-udef100.0%
Applied egg-rr100.0%
fma-udef100.0%
Applied egg-rr100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
associate-/r/100.0%
metadata-eval100.0%
associate-/r/100.0%
metadata-eval100.0%
swap-sqr100.0%
metadata-eval100.0%
add-sqr-sqrt100.0%
+-commutative100.0%
distribute-rgt-in100.0%
metadata-eval100.0%
associate-*r*100.0%
associate-*l*100.0%
metadata-eval100.0%
Applied egg-rr100.0%
distribute-lft-in100.0%
metadata-eval100.0%
*-commutative100.0%
associate-*r*100.0%
metadata-eval100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (* (sqrt 2.0) (+ (* (* v v) -0.625) 0.25)))
double code(double v) {
return sqrt(2.0) * (((v * v) * -0.625) + 0.25);
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(2.0d0) * (((v * v) * (-0.625d0)) + 0.25d0)
end function
public static double code(double v) {
return Math.sqrt(2.0) * (((v * v) * -0.625) + 0.25);
}
def code(v): return math.sqrt(2.0) * (((v * v) * -0.625) + 0.25)
function code(v) return Float64(sqrt(2.0) * Float64(Float64(Float64(v * v) * -0.625) + 0.25)) end
function tmp = code(v) tmp = sqrt(2.0) * (((v * v) * -0.625) + 0.25); end
code[v_] := N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[(N[(v * v), $MachinePrecision] * -0.625), $MachinePrecision] + 0.25), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2} \cdot \left(\left(v \cdot v\right) \cdot -0.625 + 0.25\right)
\end{array}
Initial program 100.0%
associate-*r*100.0%
Simplified100.0%
Taylor expanded in v around 0 98.9%
+-commutative98.9%
associate-*r*98.9%
distribute-rgt-out98.9%
*-commutative98.9%
unpow298.9%
Simplified98.9%
Taylor expanded in v around 0 99.0%
unpow299.0%
associate-*r*99.0%
distribute-rgt-out99.0%
Simplified99.0%
Final simplification99.0%
(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}
Initial program 100.0%
associate-*r*100.0%
Simplified100.0%
associate-*l/100.0%
clear-num100.0%
sqrt-unprod100.0%
sub-neg100.0%
+-commutative100.0%
*-commutative100.0%
distribute-rgt-neg-in100.0%
distribute-lft-neg-in100.0%
metadata-eval100.0%
*-commutative100.0%
fma-udef100.0%
Applied egg-rr100.0%
fma-udef100.0%
Applied egg-rr100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
associate-/r/100.0%
metadata-eval100.0%
associate-/r/100.0%
metadata-eval100.0%
swap-sqr100.0%
metadata-eval100.0%
add-sqr-sqrt100.0%
+-commutative100.0%
distribute-rgt-in100.0%
metadata-eval100.0%
associate-*r*100.0%
associate-*l*100.0%
metadata-eval100.0%
Applied egg-rr100.0%
distribute-lft-in100.0%
metadata-eval100.0%
*-commutative100.0%
associate-*r*100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in v around 0 98.5%
Final simplification98.5%
(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%
*-commutative100.0%
sqr-neg100.0%
sqr-neg100.0%
associate-*l*100.0%
Simplified100.0%
Taylor expanded in v around 0 98.5%
Final simplification98.5%
herbie shell --seed 2023287
(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))))