
(FPCore (x) :precision binary64 (sqrt (* (* 2.0 x) x)))
double code(double x) {
return sqrt(((2.0 * x) * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt(((2.0d0 * x) * x))
end function
public static double code(double x) {
return Math.sqrt(((2.0 * x) * x));
}
def code(x): return math.sqrt(((2.0 * x) * x))
function code(x) return sqrt(Float64(Float64(2.0 * x) * x)) end
function tmp = code(x) tmp = sqrt(((2.0 * x) * x)); end
code[x_] := N[Sqrt[N[(N[(2.0 * x), $MachinePrecision] * x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\left(2 \cdot x\right) \cdot x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (sqrt (* (* 2.0 x) x)))
double code(double x) {
return sqrt(((2.0 * x) * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt(((2.0d0 * x) * x))
end function
public static double code(double x) {
return Math.sqrt(((2.0 * x) * x));
}
def code(x): return math.sqrt(((2.0 * x) * x))
function code(x) return sqrt(Float64(Float64(2.0 * x) * x)) end
function tmp = code(x) tmp = sqrt(((2.0 * x) * x)); end
code[x_] := N[Sqrt[N[(N[(2.0 * x), $MachinePrecision] * x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\left(2 \cdot x\right) \cdot x}
\end{array}
(FPCore (x) :precision binary64 (hypot x x))
double code(double x) {
return hypot(x, x);
}
public static double code(double x) {
return Math.hypot(x, x);
}
def code(x): return math.hypot(x, x)
function code(x) return hypot(x, x) end
function tmp = code(x) tmp = hypot(x, x); end
code[x_] := N[Sqrt[x ^ 2 + x ^ 2], $MachinePrecision]
\begin{array}{l}
\\
\mathsf{hypot}\left(x, x\right)
\end{array}
Initial program 52.9%
lift-sqrt.f64N/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
count-2-revN/A
lower-hypot.f64100.0
Applied rewrites100.0%
(FPCore (x) :precision binary64 (* (sqrt 2.0) x))
double code(double x) {
return sqrt(2.0) * x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt(2.0d0) * x
end function
public static double code(double x) {
return Math.sqrt(2.0) * x;
}
def code(x): return math.sqrt(2.0) * x
function code(x) return Float64(sqrt(2.0) * x) end
function tmp = code(x) tmp = sqrt(2.0) * x; end
code[x_] := N[(N[Sqrt[2.0], $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2} \cdot x
\end{array}
Initial program 52.9%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f6452.2
Applied rewrites52.2%
(FPCore (x) :precision binary64 (sqrt (+ x x)))
double code(double x) {
return sqrt((x + x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((x + x))
end function
public static double code(double x) {
return Math.sqrt((x + x));
}
def code(x): return math.sqrt((x + x))
function code(x) return sqrt(Float64(x + x)) end
function tmp = code(x) tmp = sqrt((x + x)); end
code[x_] := N[Sqrt[N[(x + x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{x + x}
\end{array}
Initial program 52.9%
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
count-2-revN/A
flip-+N/A
+-inversesN/A
+-inversesN/A
associate-*r/N/A
+-inversesN/A
+-inversesN/A
distribute-lft-out--N/A
+-inversesN/A
+-inversesN/A
flip-+N/A
lower-+.f643.6
Applied rewrites3.6%
(FPCore (x) :precision binary64 0.0)
double code(double x) {
return 0.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.0d0
end function
public static double code(double x) {
return 0.0;
}
def code(x): return 0.0
function code(x) return 0.0 end
function tmp = code(x) tmp = 0.0; end
code[x_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 52.9%
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
count-2-revN/A
flip-+N/A
+-inversesN/A
+-inversesN/A
associate-*r/N/A
+-inversesN/A
+-inversesN/A
distribute-lft-out--N/A
+-inversesN/A
+-inversesN/A
flip-+N/A
lower-+.f643.6
Applied rewrites3.6%
lift-sqrt.f64N/A
pow1/2N/A
lift-+.f64N/A
flip-+N/A
+-inversesN/A
+-inversesN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
mul0-rgtN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
mul0-rgtN/A
mul0-rgtN/A
metadata-evalN/A
mul0-rgtN/A
flip3--N/A
mul0-rgtN/A
metadata-evalN/A
metadata-eval3.8
Applied rewrites3.8%
herbie shell --seed 2024338
(FPCore (x)
:name "sqrt B (should all be same)"
:precision binary64
(sqrt (* (* 2.0 x) x)))