
(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 (let* ((t_0 (- (sqrt (+ 1.0 x)) (sqrt x)))) (if (<= t_0 2e-6) (* (pow x -0.5) 0.5) t_0)))
double code(double x) {
double t_0 = sqrt((1.0 + x)) - sqrt(x);
double tmp;
if (t_0 <= 2e-6) {
tmp = pow(x, -0.5) * 0.5;
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
real(8) :: tmp
t_0 = sqrt((1.0d0 + x)) - sqrt(x)
if (t_0 <= 2d-6) then
tmp = (x ** (-0.5d0)) * 0.5d0
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x) {
double t_0 = Math.sqrt((1.0 + x)) - Math.sqrt(x);
double tmp;
if (t_0 <= 2e-6) {
tmp = Math.pow(x, -0.5) * 0.5;
} else {
tmp = t_0;
}
return tmp;
}
def code(x): t_0 = math.sqrt((1.0 + x)) - math.sqrt(x) tmp = 0 if t_0 <= 2e-6: tmp = math.pow(x, -0.5) * 0.5 else: tmp = t_0 return tmp
function code(x) t_0 = Float64(sqrt(Float64(1.0 + x)) - sqrt(x)) tmp = 0.0 if (t_0 <= 2e-6) tmp = Float64((x ^ -0.5) * 0.5); else tmp = t_0; end return tmp end
function tmp_2 = code(x) t_0 = sqrt((1.0 + x)) - sqrt(x); tmp = 0.0; if (t_0 <= 2e-6) tmp = (x ^ -0.5) * 0.5; else tmp = t_0; end tmp_2 = tmp; end
code[x_] := Block[{t$95$0 = N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 2e-6], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision], t$95$0]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{1 + x} - \sqrt{x}\\
\mathbf{if}\;t_0 \leq 2 \cdot 10^{-6}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;t_0\\
\end{array}
\end{array}
if (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x)) < 1.99999999999999991e-6Initial program 4.3%
flip3--2.9%
sqrt-pow23.2%
metadata-eval3.2%
sqrt-pow22.9%
metadata-eval2.9%
add-sqr-sqrt2.9%
add-sqr-sqrt2.9%
associate-+r+2.9%
sqrt-unprod2.9%
add-sqr-sqrt2.9%
pow22.9%
metadata-eval2.9%
add-sqr-sqrt2.9%
pow12.9%
pow-plus2.9%
pow-prod-down2.9%
Applied egg-rr2.9%
Taylor expanded in x around inf 99.6%
*-commutative99.6%
Simplified99.6%
expm1-log1p-u99.6%
expm1-udef6.4%
inv-pow6.4%
sqrt-pow16.4%
metadata-eval6.4%
Applied egg-rr6.4%
expm1-def99.8%
expm1-log1p99.8%
Simplified99.8%
if 1.99999999999999991e-6 < (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x)) Initial program 99.8%
Final simplification99.8%
(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 49.1%
flip--49.0%
div-inv49.0%
add-sqr-sqrt49.3%
add-sqr-sqrt49.6%
associate--l+49.6%
Applied egg-rr49.6%
+-commutative49.6%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
associate-*r/99.7%
metadata-eval99.7%
+-commutative99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (x) :precision binary64 (if (<= x 0.6) (- 1.0 x) (* (pow x -0.5) 0.5)))
double code(double x) {
double tmp;
if (x <= 0.6) {
tmp = 1.0 - x;
} else {
tmp = pow(x, -0.5) * 0.5;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.6d0) then
tmp = 1.0d0 - x
else
tmp = (x ** (-0.5d0)) * 0.5d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.6) {
tmp = 1.0 - x;
} else {
tmp = Math.pow(x, -0.5) * 0.5;
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.6: tmp = 1.0 - x else: tmp = math.pow(x, -0.5) * 0.5 return tmp
function code(x) tmp = 0.0 if (x <= 0.6) tmp = Float64(1.0 - x); else tmp = Float64((x ^ -0.5) * 0.5); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.6) tmp = 1.0 - x; else tmp = (x ^ -0.5) * 0.5; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.6], N[(1.0 - x), $MachinePrecision], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.6:\\
\;\;\;\;1 - x\\
\mathbf{else}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\
\end{array}
\end{array}
if x < 0.599999999999999978Initial program 99.9%
flip--99.8%
div-inv99.8%
add-sqr-sqrt99.9%
add-sqr-sqrt99.9%
associate--l+99.9%
Applied egg-rr99.9%
+-commutative99.9%
associate-+l-99.9%
+-inverses99.9%
metadata-eval99.9%
associate-*r/99.9%
metadata-eval99.9%
+-commutative99.9%
Simplified99.9%
Applied egg-rr94.8%
Taylor expanded in x around 0 94.8%
neg-mul-194.8%
unsub-neg94.8%
Simplified94.8%
if 0.599999999999999978 < x Initial program 4.9%
flip3--3.5%
sqrt-pow23.8%
metadata-eval3.8%
sqrt-pow23.5%
metadata-eval3.5%
add-sqr-sqrt3.5%
add-sqr-sqrt3.5%
associate-+r+3.5%
sqrt-unprod3.5%
add-sqr-sqrt3.5%
pow23.5%
metadata-eval3.5%
add-sqr-sqrt3.5%
pow13.5%
pow-plus3.5%
pow-prod-down3.5%
Applied egg-rr3.5%
Taylor expanded in x around inf 99.2%
*-commutative99.2%
Simplified99.2%
expm1-log1p-u99.2%
expm1-udef6.7%
inv-pow6.7%
sqrt-pow16.7%
metadata-eval6.7%
Applied egg-rr6.7%
expm1-def99.3%
expm1-log1p99.3%
Simplified99.3%
Final simplification97.2%
(FPCore (x) :precision binary64 (/ 1.0 (+ 1.0 x)))
double code(double x) {
return 1.0 / (1.0 + x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0 / (1.0d0 + x)
end function
public static double code(double x) {
return 1.0 / (1.0 + x);
}
def code(x): return 1.0 / (1.0 + x)
function code(x) return Float64(1.0 / Float64(1.0 + x)) end
function tmp = code(x) tmp = 1.0 / (1.0 + x); end
code[x_] := N[(1.0 / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{1 + x}
\end{array}
Initial program 49.1%
flip--49.0%
div-inv49.0%
add-sqr-sqrt49.3%
add-sqr-sqrt49.6%
associate--l+49.6%
Applied egg-rr49.6%
+-commutative49.6%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
associate-*r/99.7%
metadata-eval99.7%
+-commutative99.7%
Simplified99.7%
Applied egg-rr54.9%
Taylor expanded in x around 0 47.7%
+-commutative47.7%
Simplified47.7%
Final simplification47.7%
(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 49.1%
Taylor expanded in x around 0 47.6%
Final simplification47.6%
(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 2024019
(FPCore (x)
:name "Main:bigenough3 from C"
:precision binary64
:herbie-target
(/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x)))
(- (sqrt (+ x 1.0)) (sqrt x)))