
(FPCore (x) :precision binary64 (- (sqrt (+ x 1.0)) (sqrt x)))
double code(double x) {
return sqrt((x + 1.0)) - sqrt(x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((x + 1.0d0)) - sqrt(x)
end function
public static double code(double x) {
return Math.sqrt((x + 1.0)) - Math.sqrt(x);
}
def code(x): return math.sqrt((x + 1.0)) - math.sqrt(x)
function code(x) return Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) end
function tmp = code(x) tmp = sqrt((x + 1.0)) - sqrt(x); end
code[x_] := N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{x + 1} - \sqrt{x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (sqrt (+ x 1.0)) (sqrt x)))
double code(double x) {
return sqrt((x + 1.0)) - sqrt(x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((x + 1.0d0)) - sqrt(x)
end function
public static double code(double x) {
return Math.sqrt((x + 1.0)) - Math.sqrt(x);
}
def code(x): return math.sqrt((x + 1.0)) - math.sqrt(x)
function code(x) return Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) end
function tmp = code(x) tmp = sqrt((x + 1.0)) - sqrt(x); end
code[x_] := N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{x + 1} - \sqrt{x}
\end{array}
(FPCore (x) :precision binary64 (/ 1.0 (+ (sqrt x) (sqrt (+ 1.0 x)))))
double code(double x) {
return 1.0 / (sqrt(x) + sqrt((1.0 + x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0 / (sqrt(x) + sqrt((1.0d0 + x)))
end function
public static double code(double x) {
return 1.0 / (Math.sqrt(x) + Math.sqrt((1.0 + x)));
}
def code(x): return 1.0 / (math.sqrt(x) + math.sqrt((1.0 + x)))
function code(x) return Float64(1.0 / Float64(sqrt(x) + sqrt(Float64(1.0 + x)))) end
function tmp = code(x) tmp = 1.0 / (sqrt(x) + sqrt((1.0 + x))); end
code[x_] := N[(1.0 / N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{x} + \sqrt{1 + x}}
\end{array}
Initial program 7.4%
flip--8.5%
div-inv8.5%
add-sqr-sqrt8.6%
add-sqr-sqrt9.8%
associate--l+9.8%
Applied egg-rr9.8%
associate-*r/9.8%
*-rgt-identity9.8%
+-commutative9.8%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
(FPCore (x) :precision binary64 (* 0.5 (pow x -0.5)))
double code(double x) {
return 0.5 * pow(x, -0.5);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.5d0 * (x ** (-0.5d0))
end function
public static double code(double x) {
return 0.5 * Math.pow(x, -0.5);
}
def code(x): return 0.5 * math.pow(x, -0.5)
function code(x) return Float64(0.5 * (x ^ -0.5)) end
function tmp = code(x) tmp = 0.5 * (x ^ -0.5); end
code[x_] := N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot {x}^{-0.5}
\end{array}
Initial program 7.4%
flip--8.5%
div-inv8.5%
add-sqr-sqrt8.6%
add-sqr-sqrt9.8%
associate--l+9.8%
Applied egg-rr9.8%
associate-*r/9.8%
*-rgt-identity9.8%
+-commutative9.8%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around inf 97.4%
unpow-197.4%
metadata-eval97.4%
pow-sqr97.6%
rem-sqrt-square97.6%
rem-square-sqrt96.7%
fabs-sqr96.7%
rem-square-sqrt97.6%
Simplified97.6%
(FPCore (x) :precision binary64 (sqrt (/ 0.25 x)))
double code(double x) {
return sqrt((0.25 / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((0.25d0 / x))
end function
public static double code(double x) {
return Math.sqrt((0.25 / x));
}
def code(x): return math.sqrt((0.25 / x))
function code(x) return sqrt(Float64(0.25 / x)) end
function tmp = code(x) tmp = sqrt((0.25 / x)); end
code[x_] := N[Sqrt[N[(0.25 / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{0.25}{x}}
\end{array}
Initial program 7.4%
Taylor expanded in x around inf 97.4%
add-sqr-sqrt96.8%
sqrt-unprod97.4%
*-commutative97.4%
*-commutative97.4%
swap-sqr97.4%
add-sqr-sqrt97.4%
metadata-eval97.4%
Applied egg-rr97.4%
associate-*l/97.4%
metadata-eval97.4%
Simplified97.4%
(FPCore (x) :precision binary64 (pow x -0.5))
double code(double x) {
return pow(x, -0.5);
}
real(8) function code(x)
real(8), intent (in) :: x
code = x ** (-0.5d0)
end function
public static double code(double x) {
return Math.pow(x, -0.5);
}
def code(x): return math.pow(x, -0.5)
function code(x) return x ^ -0.5 end
function tmp = code(x) tmp = x ^ -0.5; end
code[x_] := N[Power[x, -0.5], $MachinePrecision]
\begin{array}{l}
\\
{x}^{-0.5}
\end{array}
Initial program 7.4%
Taylor expanded in x around 0 1.6%
Taylor expanded in x around inf 1.6%
neg-mul-11.6%
Simplified1.6%
add-sqr-sqrt0.0%
sqrt-unprod5.5%
pow1/25.5%
metadata-eval5.5%
pow-pow5.5%
pow1/35.5%
pow1/25.5%
metadata-eval5.5%
pow-pow5.5%
pow1/35.5%
sqr-neg5.5%
pow-sqr5.5%
metadata-eval5.5%
pow35.5%
add-cube-cbrt5.5%
pow1/25.5%
add-exp-log5.5%
add-sqr-sqrt5.5%
sqrt-unprod5.5%
sqr-neg5.5%
sqrt-unprod0.0%
add-sqr-sqrt18.7%
Applied egg-rr18.7%
(FPCore (x) :precision binary64 1.0)
double code(double x) {
return 1.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0
end function
public static double code(double x) {
return 1.0;
}
def code(x): return 1.0
function code(x) return 1.0 end
function tmp = code(x) tmp = 1.0; end
code[x_] := 1.0
\begin{array}{l}
\\
1
\end{array}
Initial program 7.4%
flip--8.5%
div-inv8.5%
add-sqr-sqrt8.6%
add-sqr-sqrt9.8%
associate--l+9.8%
Applied egg-rr9.8%
associate-*r/9.8%
*-rgt-identity9.8%
+-commutative9.8%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
pow1/299.5%
*-rgt-identity99.5%
add-cube-cbrt99.1%
associate-*l*99.1%
unpow-prod-down99.1%
pow299.1%
pow-pow99.1%
metadata-eval99.1%
pow199.1%
Applied egg-rr99.1%
*-commutative99.1%
*-rgt-identity99.1%
pow-plus99.1%
metadata-eval99.1%
Simplified99.1%
Applied egg-rr0.8%
log1p-undefine0.8%
rem-exp-log0.8%
associate--r+7.1%
+-inverses7.1%
metadata-eval7.1%
metadata-eval7.1%
metadata-eval7.1%
metadata-eval7.1%
metadata-eval7.1%
Simplified7.1%
(FPCore (x) :precision binary64 (/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x))))
double code(double x) {
return 1.0 / (sqrt((x + 1.0)) + sqrt(x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0 / (sqrt((x + 1.0d0)) + sqrt(x))
end function
public static double code(double x) {
return 1.0 / (Math.sqrt((x + 1.0)) + Math.sqrt(x));
}
def code(x): return 1.0 / (math.sqrt((x + 1.0)) + math.sqrt(x))
function code(x) return Float64(1.0 / Float64(sqrt(Float64(x + 1.0)) + sqrt(x))) end
function tmp = code(x) tmp = 1.0 / (sqrt((x + 1.0)) + sqrt(x)); end
code[x_] := N[(1.0 / N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{x + 1} + \sqrt{x}}
\end{array}
herbie shell --seed 2024117
(FPCore (x)
:name "2sqrt (example 3.1)"
:precision binary64
:pre (and (> x 1.0) (< x 1e+308))
:alt
(! :herbie-platform default (/ 1 (+ (sqrt (+ x 1)) (sqrt x))))
(- (sqrt (+ x 1.0)) (sqrt x)))