
(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 0.125) (* (sqrt (+ 1.0 (* -3.0 (* v v)))) (- 1.0 (* v v)))))
double code(double v) {
return sqrt(0.125) * (sqrt((1.0 + (-3.0 * (v * v)))) * (1.0 - (v * v)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(0.125d0) * (sqrt((1.0d0 + ((-3.0d0) * (v * v)))) * (1.0d0 - (v * v)))
end function
public static double code(double v) {
return Math.sqrt(0.125) * (Math.sqrt((1.0 + (-3.0 * (v * v)))) * (1.0 - (v * v)));
}
def code(v): return math.sqrt(0.125) * (math.sqrt((1.0 + (-3.0 * (v * v)))) * (1.0 - (v * v)))
function code(v) return Float64(sqrt(0.125) * Float64(sqrt(Float64(1.0 + Float64(-3.0 * Float64(v * v)))) * Float64(1.0 - Float64(v * v)))) end
function tmp = code(v) tmp = sqrt(0.125) * (sqrt((1.0 + (-3.0 * (v * v)))) * (1.0 - (v * v))); end
code[v_] := N[(N[Sqrt[0.125], $MachinePrecision] * N[(N[Sqrt[N[(1.0 + N[(-3.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.125} \cdot \left(\sqrt{1 + -3 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\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%
add-log-exp100.0%
*-un-lft-identity100.0%
log-prod100.0%
metadata-eval100.0%
add-log-exp100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
frac-times100.0%
rem-square-sqrt100.0%
metadata-eval100.0%
metadata-eval100.0%
Applied egg-rr100.0%
+-lft-identity100.0%
Simplified100.0%
(FPCore (v) :precision binary64 (* (sqrt 0.125) (+ 1.0 (* (* v v) -2.5))))
double code(double v) {
return sqrt(0.125) * (1.0 + ((v * v) * -2.5));
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(0.125d0) * (1.0d0 + ((v * v) * (-2.5d0)))
end function
public static double code(double v) {
return Math.sqrt(0.125) * (1.0 + ((v * v) * -2.5));
}
def code(v): return math.sqrt(0.125) * (1.0 + ((v * v) * -2.5))
function code(v) return Float64(sqrt(0.125) * Float64(1.0 + Float64(Float64(v * v) * -2.5))) end
function tmp = code(v) tmp = sqrt(0.125) * (1.0 + ((v * v) * -2.5)); end
code[v_] := N[(N[Sqrt[0.125], $MachinePrecision] * N[(1.0 + N[(N[(v * v), $MachinePrecision] * -2.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.125} \cdot \left(1 + \left(v \cdot v\right) \cdot -2.5\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 99.6%
*-commutative99.6%
Simplified99.6%
pow299.6%
Applied egg-rr99.6%
add-log-exp100.0%
*-un-lft-identity100.0%
log-prod100.0%
metadata-eval100.0%
add-log-exp100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
frac-times100.0%
rem-square-sqrt100.0%
metadata-eval100.0%
metadata-eval100.0%
Applied egg-rr99.6%
+-lft-identity100.0%
Simplified99.6%
(FPCore (v) :precision binary64 (* (sqrt 0.125) (- 1.0 (* v v))))
double code(double v) {
return sqrt(0.125) * (1.0 - (v * v));
}
real(8) function code(v)
real(8), intent (in) :: v
code = sqrt(0.125d0) * (1.0d0 - (v * v))
end function
public static double code(double v) {
return Math.sqrt(0.125) * (1.0 - (v * v));
}
def code(v): return math.sqrt(0.125) * (1.0 - (v * v))
function code(v) return Float64(sqrt(0.125) * Float64(1.0 - Float64(v * v))) end
function tmp = code(v) tmp = sqrt(0.125) * (1.0 - (v * v)); end
code[v_] := N[(N[Sqrt[0.125], $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{0.125} \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 98.6%
add-log-exp100.0%
*-un-lft-identity100.0%
log-prod100.0%
metadata-eval100.0%
add-log-exp100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
frac-times100.0%
rem-square-sqrt100.0%
metadata-eval100.0%
metadata-eval100.0%
Applied egg-rr98.6%
+-lft-identity100.0%
Simplified98.6%
Final simplification98.6%
(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%
add-log-exp100.0%
*-un-lft-identity100.0%
log-prod100.0%
metadata-eval100.0%
add-log-exp100.0%
add-sqr-sqrt98.4%
sqrt-unprod100.0%
frac-times100.0%
rem-square-sqrt100.0%
metadata-eval100.0%
metadata-eval100.0%
Applied egg-rr100.0%
+-lft-identity100.0%
Simplified100.0%
Taylor expanded in v around 0 98.6%
herbie shell --seed 2024149
(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))))