
(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 (+ 1.0 x)) (sqrt x))))
double code(double x) {
return 1.0 / (sqrt((1.0 + x)) + sqrt(x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0 / (sqrt((1.0d0 + x)) + sqrt(x))
end function
public static double code(double x) {
return 1.0 / (Math.sqrt((1.0 + x)) + Math.sqrt(x));
}
def code(x): return 1.0 / (math.sqrt((1.0 + x)) + math.sqrt(x))
function code(x) return Float64(1.0 / Float64(sqrt(Float64(1.0 + x)) + sqrt(x))) end
function tmp = code(x) tmp = 1.0 / (sqrt((1.0 + x)) + sqrt(x)); end
code[x_] := N[(1.0 / N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{1 + x} + \sqrt{x}}
\end{array}
Initial program 54.8%
flip--55.1%
div-inv55.1%
add-sqr-sqrt54.9%
add-sqr-sqrt55.3%
associate--l+55.3%
Applied egg-rr55.3%
+-commutative55.3%
associate-+l-99.8%
+-inverses99.8%
metadata-eval99.8%
associate-*r/99.8%
metadata-eval99.8%
+-commutative99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (x) :precision binary64 (let* ((t_0 (- (sqrt (+ 1.0 x)) (sqrt x)))) (if (<= t_0 1e-6) (* 0.5 (pow x -0.5)) t_0)))
double code(double x) {
double t_0 = sqrt((1.0 + x)) - sqrt(x);
double tmp;
if (t_0 <= 1e-6) {
tmp = 0.5 * pow(x, -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 <= 1d-6) then
tmp = 0.5d0 * (x ** (-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 <= 1e-6) {
tmp = 0.5 * Math.pow(x, -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 <= 1e-6: tmp = 0.5 * math.pow(x, -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 <= 1e-6) tmp = Float64(0.5 * (x ^ -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 <= 1e-6) tmp = 0.5 * (x ^ -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, 1e-6], N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision], t$95$0]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{1 + x} - \sqrt{x}\\
\mathbf{if}\;t\_0 \leq 10^{-6}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x)) < 9.99999999999999955e-7Initial program 4.2%
flip--4.6%
div-inv4.6%
add-sqr-sqrt3.8%
add-sqr-sqrt4.6%
associate--l+4.6%
Applied egg-rr4.6%
+-commutative4.6%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
associate-*r/99.7%
metadata-eval99.7%
+-commutative99.7%
Simplified99.7%
flip3-+68.6%
associate-/r/68.4%
pow1/268.4%
+-commutative68.4%
pow-pow68.4%
+-commutative68.4%
metadata-eval68.4%
sqrt-pow268.3%
metadata-eval68.3%
add-sqr-sqrt68.5%
+-commutative68.5%
add-sqr-sqrt68.2%
Applied egg-rr48.3%
Taylor expanded in x around inf 99.6%
expm1-log1p-u99.6%
expm1-udef5.9%
inv-pow5.9%
sqrt-pow15.9%
metadata-eval5.9%
Applied egg-rr5.9%
expm1-def99.8%
expm1-log1p99.8%
Simplified99.8%
if 9.99999999999999955e-7 < (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x)) Initial program 99.5%
Final simplification99.7%
(FPCore (x) :precision binary64 (if (<= x 1.0) (/ 1.0 (+ 1.0 (sqrt x))) (* 0.5 (pow x -0.5))))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 1.0 / (1.0 + sqrt(x));
} else {
tmp = 0.5 * pow(x, -0.5);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 1.0d0) then
tmp = 1.0d0 / (1.0d0 + sqrt(x))
else
tmp = 0.5d0 * (x ** (-0.5d0))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 1.0 / (1.0 + Math.sqrt(x));
} else {
tmp = 0.5 * Math.pow(x, -0.5);
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.0: tmp = 1.0 / (1.0 + math.sqrt(x)) else: tmp = 0.5 * math.pow(x, -0.5) return tmp
function code(x) tmp = 0.0 if (x <= 1.0) tmp = Float64(1.0 / Float64(1.0 + sqrt(x))); else tmp = Float64(0.5 * (x ^ -0.5)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 1.0) tmp = 1.0 / (1.0 + sqrt(x)); else tmp = 0.5 * (x ^ -0.5); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.0], N[(1.0 / N[(1.0 + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;\frac{1}{1 + \sqrt{x}}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\end{array}
\end{array}
if x < 1Initial program 100.0%
flip--99.9%
div-inv99.9%
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%
add-sqr-sqrt99.9%
sqrt-unprod99.9%
inv-pow99.9%
inv-pow99.9%
pow-prod-up99.9%
+-commutative99.9%
metadata-eval99.9%
Applied egg-rr99.9%
sqrt-pow199.9%
sqrt-pow299.9%
+-commutative99.9%
add-sqr-sqrt99.9%
add-sqr-sqrt99.9%
hypot-def99.9%
pow1/299.9%
sqrt-pow199.9%
+-commutative99.9%
metadata-eval99.9%
pow1/299.9%
sqrt-pow199.9%
metadata-eval99.9%
Applied egg-rr99.9%
Taylor expanded in x around 0 97.2%
if 1 < x Initial program 5.3%
flip--6.0%
div-inv6.0%
add-sqr-sqrt5.4%
add-sqr-sqrt6.2%
associate--l+6.2%
Applied egg-rr6.2%
+-commutative6.2%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
associate-*r/99.7%
metadata-eval99.7%
+-commutative99.7%
Simplified99.7%
flip3-+69.1%
associate-/r/68.9%
pow1/268.9%
+-commutative68.9%
pow-pow69.0%
+-commutative69.0%
metadata-eval69.0%
sqrt-pow268.8%
metadata-eval68.8%
add-sqr-sqrt69.0%
+-commutative69.0%
add-sqr-sqrt68.8%
Applied egg-rr49.1%
Taylor expanded in x around inf 98.9%
expm1-log1p-u98.9%
expm1-udef6.7%
inv-pow6.7%
sqrt-pow16.7%
metadata-eval6.7%
Applied egg-rr6.7%
expm1-def99.1%
expm1-log1p99.1%
Simplified99.1%
Final simplification98.1%
(FPCore (x) :precision binary64 (if (<= x 0.25) 1.0 (* 0.5 (pow x -0.5))))
double code(double x) {
double tmp;
if (x <= 0.25) {
tmp = 1.0;
} else {
tmp = 0.5 * pow(x, -0.5);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.25d0) then
tmp = 1.0d0
else
tmp = 0.5d0 * (x ** (-0.5d0))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.25) {
tmp = 1.0;
} else {
tmp = 0.5 * Math.pow(x, -0.5);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.25: tmp = 1.0 else: tmp = 0.5 * math.pow(x, -0.5) return tmp
function code(x) tmp = 0.0 if (x <= 0.25) tmp = 1.0; else tmp = Float64(0.5 * (x ^ -0.5)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.25) tmp = 1.0; else tmp = 0.5 * (x ^ -0.5); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.25], 1.0, N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.25:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\end{array}
\end{array}
if x < 0.25Initial program 100.0%
Taylor expanded in x around 0 96.6%
if 0.25 < x Initial program 6.0%
flip--6.8%
div-inv6.8%
add-sqr-sqrt6.1%
add-sqr-sqrt7.0%
associate--l+7.0%
Applied egg-rr7.0%
+-commutative7.0%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
associate-*r/99.7%
metadata-eval99.7%
+-commutative99.7%
Simplified99.7%
flip3-+69.3%
associate-/r/69.2%
pow1/269.2%
+-commutative69.2%
pow-pow69.2%
+-commutative69.2%
metadata-eval69.2%
sqrt-pow269.1%
metadata-eval69.1%
add-sqr-sqrt69.3%
+-commutative69.3%
add-sqr-sqrt69.0%
Applied egg-rr49.5%
Taylor expanded in x around inf 98.2%
expm1-log1p-u98.2%
expm1-udef6.8%
inv-pow6.8%
sqrt-pow16.8%
metadata-eval6.8%
Applied egg-rr6.8%
expm1-def98.4%
expm1-log1p98.4%
Simplified98.4%
Final simplification97.5%
(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 54.8%
Taylor expanded in x around 0 53.4%
Final simplification53.4%
(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 2024026
(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)))