
(FPCore (v) :precision binary64 (acos (/ (- 1.0 (* 5.0 (* v v))) (- (* v v) 1.0))))
double code(double v) {
return acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos(((1.0d0 - (5.0d0 * (v * v))) / ((v * v) - 1.0d0)))
end function
public static double code(double v) {
return Math.acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)));
}
def code(v): return math.acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)))
function code(v) return acos(Float64(Float64(1.0 - Float64(5.0 * Float64(v * v))) / Float64(Float64(v * v) - 1.0))) end
function tmp = code(v) tmp = acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0))); end
code[v_] := N[ArcCos[N[(N[(1.0 - N[(5.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(v * v), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (v) :precision binary64 (acos (/ (- 1.0 (* 5.0 (* v v))) (- (* v v) 1.0))))
double code(double v) {
return acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos(((1.0d0 - (5.0d0 * (v * v))) / ((v * v) - 1.0d0)))
end function
public static double code(double v) {
return Math.acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)));
}
def code(v): return math.acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0)))
function code(v) return acos(Float64(Float64(1.0 - Float64(5.0 * Float64(v * v))) / Float64(Float64(v * v) - 1.0))) end
function tmp = code(v) tmp = acos(((1.0 - (5.0 * (v * v))) / ((v * v) - 1.0))); end
code[v_] := N[ArcCos[N[(N[(1.0 - N[(5.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(v * v), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)
\end{array}
(FPCore (v) :precision binary64 (acos (/ 1.0 (/ (+ (* v v) -1.0) (+ 1.0 (* (* v v) -5.0))))))
double code(double v) {
return acos((1.0 / (((v * v) + -1.0) / (1.0 + ((v * v) * -5.0)))));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos((1.0d0 / (((v * v) + (-1.0d0)) / (1.0d0 + ((v * v) * (-5.0d0))))))
end function
public static double code(double v) {
return Math.acos((1.0 / (((v * v) + -1.0) / (1.0 + ((v * v) * -5.0)))));
}
def code(v): return math.acos((1.0 / (((v * v) + -1.0) / (1.0 + ((v * v) * -5.0)))))
function code(v) return acos(Float64(1.0 / Float64(Float64(Float64(v * v) + -1.0) / Float64(1.0 + Float64(Float64(v * v) * -5.0))))) end
function tmp = code(v) tmp = acos((1.0 / (((v * v) + -1.0) / (1.0 + ((v * v) * -5.0))))); end
code[v_] := N[ArcCos[N[(1.0 / N[(N[(N[(v * v), $MachinePrecision] + -1.0), $MachinePrecision] / N[(1.0 + N[(N[(v * v), $MachinePrecision] * -5.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(\frac{1}{\frac{v \cdot v + -1}{1 + \left(v \cdot v\right) \cdot -5}}\right)
\end{array}
Initial program 99.1%
clear-numN/A
/-lowering-/.f64N/A
/-lowering-/.f64N/A
sub-negN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
metadata-evalN/A
sub-negN/A
+-lowering-+.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
metadata-eval99.1%
Applied egg-rr99.1%
(FPCore (v) :precision binary64 (acos (/ (- 1.0 (* (* v v) 5.0)) (+ (* v v) -1.0))))
double code(double v) {
return acos(((1.0 - ((v * v) * 5.0)) / ((v * v) + -1.0)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos(((1.0d0 - ((v * v) * 5.0d0)) / ((v * v) + (-1.0d0))))
end function
public static double code(double v) {
return Math.acos(((1.0 - ((v * v) * 5.0)) / ((v * v) + -1.0)));
}
def code(v): return math.acos(((1.0 - ((v * v) * 5.0)) / ((v * v) + -1.0)))
function code(v) return acos(Float64(Float64(1.0 - Float64(Float64(v * v) * 5.0)) / Float64(Float64(v * v) + -1.0))) end
function tmp = code(v) tmp = acos(((1.0 - ((v * v) * 5.0)) / ((v * v) + -1.0))); end
code[v_] := N[ArcCos[N[(N[(1.0 - N[(N[(v * v), $MachinePrecision] * 5.0), $MachinePrecision]), $MachinePrecision] / N[(N[(v * v), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(\frac{1 - \left(v \cdot v\right) \cdot 5}{v \cdot v + -1}\right)
\end{array}
Initial program 99.1%
Final simplification99.1%
(FPCore (v) :precision binary64 (acos (+ -1.0 (* v (* v (* 4.0 (+ 1.0 (* v v))))))))
double code(double v) {
return acos((-1.0 + (v * (v * (4.0 * (1.0 + (v * v)))))));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos(((-1.0d0) + (v * (v * (4.0d0 * (1.0d0 + (v * v)))))))
end function
public static double code(double v) {
return Math.acos((-1.0 + (v * (v * (4.0 * (1.0 + (v * v)))))));
}
def code(v): return math.acos((-1.0 + (v * (v * (4.0 * (1.0 + (v * v)))))))
function code(v) return acos(Float64(-1.0 + Float64(v * Float64(v * Float64(4.0 * Float64(1.0 + Float64(v * v))))))) end
function tmp = code(v) tmp = acos((-1.0 + (v * (v * (4.0 * (1.0 + (v * v))))))); end
code[v_] := N[ArcCos[N[(-1.0 + N[(v * N[(v * N[(4.0 * N[(1.0 + N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(-1 + v \cdot \left(v \cdot \left(4 \cdot \left(1 + v \cdot v\right)\right)\right)\right)
\end{array}
Initial program 99.1%
Taylor expanded in v around 0
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f64N/A
unpow2N/A
associate-*l*N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
*-commutativeN/A
distribute-rgt1-inN/A
*-commutativeN/A
*-lowering-*.f64N/A
+-commutativeN/A
+-lowering-+.f64N/A
unpow2N/A
*-lowering-*.f6499.1%
Simplified99.1%
(FPCore (v) :precision binary64 (acos (+ -1.0 (* (* v v) 4.0))))
double code(double v) {
return acos((-1.0 + ((v * v) * 4.0)));
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos(((-1.0d0) + ((v * v) * 4.0d0)))
end function
public static double code(double v) {
return Math.acos((-1.0 + ((v * v) * 4.0)));
}
def code(v): return math.acos((-1.0 + ((v * v) * 4.0)))
function code(v) return acos(Float64(-1.0 + Float64(Float64(v * v) * 4.0))) end
function tmp = code(v) tmp = acos((-1.0 + ((v * v) * 4.0))); end
code[v_] := N[ArcCos[N[(-1.0 + N[(N[(v * v), $MachinePrecision] * 4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} \left(-1 + \left(v \cdot v\right) \cdot 4\right)
\end{array}
Initial program 99.1%
Taylor expanded in v around 0
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6498.7%
Simplified98.7%
(FPCore (v) :precision binary64 (acos -1.0))
double code(double v) {
return acos(-1.0);
}
real(8) function code(v)
real(8), intent (in) :: v
code = acos((-1.0d0))
end function
public static double code(double v) {
return Math.acos(-1.0);
}
def code(v): return math.acos(-1.0)
function code(v) return acos(-1.0) end
function tmp = code(v) tmp = acos(-1.0); end
code[v_] := N[ArcCos[-1.0], $MachinePrecision]
\begin{array}{l}
\\
\cos^{-1} -1
\end{array}
Initial program 99.1%
Taylor expanded in v around 0
Simplified98.0%
herbie shell --seed 2024144
(FPCore (v)
:name "Falkner and Boettcher, Appendix B, 1"
:precision binary64
(acos (/ (- 1.0 (* 5.0 (* v v))) (- (* v v) 1.0))))