
(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 8 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 53.4%
flip--53.6%
div-inv53.6%
add-sqr-sqrt53.6%
add-sqr-sqrt54.5%
associate--l+54.5%
Applied egg-rr54.5%
associate-*r/54.5%
*-rgt-identity54.5%
+-commutative54.5%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
+-commutative99.7%
+-commutative99.7%
Simplified99.7%
(FPCore (x) :precision binary64 (let* ((t_0 (- (sqrt (+ 1.0 x)) (sqrt x)))) (if (<= t_0 5e-5) (* 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 <= 5e-5) {
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 <= 5d-5) 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 <= 5e-5) {
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 <= 5e-5: 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 <= 5e-5) 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 <= 5e-5) 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, 5e-5], 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 5 \cdot 10^{-5}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) < 5.00000000000000024e-5Initial program 5.1%
flip--5.3%
div-inv5.3%
add-sqr-sqrt5.0%
add-sqr-sqrt7.0%
associate--l+7.0%
Applied egg-rr7.0%
associate-*r/7.0%
*-rgt-identity7.0%
+-commutative7.0%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around inf 99.2%
rem-exp-log91.7%
exp-neg91.7%
unpow1/291.7%
exp-prod91.7%
distribute-lft-neg-out91.7%
distribute-rgt-neg-in91.7%
metadata-eval91.7%
exp-to-pow99.4%
Simplified99.4%
if 5.00000000000000024e-5 < (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) Initial program 99.5%
Final simplification99.5%
(FPCore (x) :precision binary64 (if (<= x 1.25) (- (+ 1.0 (* x (+ 0.5 (* x -0.125)))) (sqrt x)) (* 0.5 (pow x -0.5))))
double code(double x) {
double tmp;
if (x <= 1.25) {
tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - 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 <= 1.25d0) then
tmp = (1.0d0 + (x * (0.5d0 + (x * (-0.125d0))))) - 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 <= 1.25) {
tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - Math.sqrt(x);
} else {
tmp = 0.5 * Math.pow(x, -0.5);
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.25: tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - math.sqrt(x) else: tmp = 0.5 * math.pow(x, -0.5) return tmp
function code(x) tmp = 0.0 if (x <= 1.25) tmp = Float64(Float64(1.0 + Float64(x * Float64(0.5 + Float64(x * -0.125)))) - sqrt(x)); else tmp = Float64(0.5 * (x ^ -0.5)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 1.25) tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - sqrt(x); else tmp = 0.5 * (x ^ -0.5); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.25], N[(N[(1.0 + N[(x * N[(0.5 + N[(x * -0.125), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.25:\\
\;\;\;\;\left(1 + x \cdot \left(0.5 + x \cdot -0.125\right)\right) - \sqrt{x}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\end{array}
\end{array}
if x < 1.25Initial program 100.0%
Taylor expanded in x around 0 100.0%
*-commutative100.0%
Simplified100.0%
if 1.25 < x Initial program 6.1%
flip--6.6%
div-inv6.6%
add-sqr-sqrt6.5%
add-sqr-sqrt8.4%
associate--l+8.4%
Applied egg-rr8.4%
associate-*r/8.4%
*-rgt-identity8.4%
+-commutative8.4%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around inf 98.5%
rem-exp-log91.1%
exp-neg91.1%
unpow1/291.1%
exp-prod91.1%
distribute-lft-neg-out91.1%
distribute-rgt-neg-in91.1%
metadata-eval91.1%
exp-to-pow98.7%
Simplified98.7%
(FPCore (x) :precision binary64 (if (<= x 1.0) (+ 1.0 (- (* x 0.5) (sqrt x))) (* 0.5 (pow x -0.5))))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 1.0 + ((x * 0.5) - 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 + ((x * 0.5d0) - 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 + ((x * 0.5) - 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 + ((x * 0.5) - 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(Float64(x * 0.5) - 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 + ((x * 0.5) - 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[(N[(x * 0.5), $MachinePrecision] - 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:\\
\;\;\;\;1 + \left(x \cdot 0.5 - \sqrt{x}\right)\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\end{array}
\end{array}
if x < 1Initial program 100.0%
Taylor expanded in x around 0 99.8%
associate--l+99.8%
*-commutative99.8%
Simplified99.8%
if 1 < x Initial program 6.1%
flip--6.6%
div-inv6.6%
add-sqr-sqrt6.5%
add-sqr-sqrt8.4%
associate--l+8.4%
Applied egg-rr8.4%
associate-*r/8.4%
*-rgt-identity8.4%
+-commutative8.4%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around inf 98.5%
rem-exp-log91.1%
exp-neg91.1%
unpow1/291.1%
exp-prod91.1%
distribute-lft-neg-out91.1%
distribute-rgt-neg-in91.1%
metadata-eval91.1%
exp-to-pow98.7%
Simplified98.7%
(FPCore (x) :precision binary64 (if (<= x 0.36) (- 1.0 (sqrt x)) (* 0.5 (pow x -0.5))))
double code(double x) {
double tmp;
if (x <= 0.36) {
tmp = 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 <= 0.36d0) then
tmp = 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 <= 0.36) {
tmp = 1.0 - Math.sqrt(x);
} else {
tmp = 0.5 * Math.pow(x, -0.5);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.36: tmp = 1.0 - math.sqrt(x) else: tmp = 0.5 * math.pow(x, -0.5) return tmp
function code(x) tmp = 0.0 if (x <= 0.36) tmp = 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 <= 0.36) tmp = 1.0 - sqrt(x); else tmp = 0.5 * (x ^ -0.5); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.36], N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Power[x, -0.5], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.36:\\
\;\;\;\;1 - \sqrt{x}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot {x}^{-0.5}\\
\end{array}
\end{array}
if x < 0.35999999999999999Initial program 100.0%
Taylor expanded in x around 0 98.9%
if 0.35999999999999999 < x Initial program 6.1%
flip--6.6%
div-inv6.6%
add-sqr-sqrt6.5%
add-sqr-sqrt8.4%
associate--l+8.4%
Applied egg-rr8.4%
associate-*r/8.4%
*-rgt-identity8.4%
+-commutative8.4%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around inf 98.5%
rem-exp-log91.1%
exp-neg91.1%
unpow1/291.1%
exp-prod91.1%
distribute-lft-neg-out91.1%
distribute-rgt-neg-in91.1%
metadata-eval91.1%
exp-to-pow98.7%
Simplified98.7%
(FPCore (x) :precision binary64 (if (<= x 0.65) (- 1.0 (sqrt x)) (pow x -0.5)))
double code(double x) {
double tmp;
if (x <= 0.65) {
tmp = 1.0 - sqrt(x);
} else {
tmp = pow(x, -0.5);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.65d0) then
tmp = 1.0d0 - sqrt(x)
else
tmp = x ** (-0.5d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.65) {
tmp = 1.0 - Math.sqrt(x);
} else {
tmp = Math.pow(x, -0.5);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.65: tmp = 1.0 - math.sqrt(x) else: tmp = math.pow(x, -0.5) return tmp
function code(x) tmp = 0.0 if (x <= 0.65) tmp = Float64(1.0 - sqrt(x)); else tmp = x ^ -0.5; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.65) tmp = 1.0 - sqrt(x); else tmp = x ^ -0.5; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.65], N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[Power[x, -0.5], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.65:\\
\;\;\;\;1 - \sqrt{x}\\
\mathbf{else}:\\
\;\;\;\;{x}^{-0.5}\\
\end{array}
\end{array}
if x < 0.650000000000000022Initial program 100.0%
Taylor expanded in x around 0 98.9%
if 0.650000000000000022 < x Initial program 6.1%
flip--6.6%
div-inv6.6%
add-sqr-sqrt6.5%
add-sqr-sqrt8.4%
associate--l+8.4%
Applied egg-rr8.4%
associate-*r/8.4%
*-rgt-identity8.4%
+-commutative8.4%
associate-+l-99.5%
+-inverses99.5%
metadata-eval99.5%
+-commutative99.5%
+-commutative99.5%
Simplified99.5%
Taylor expanded in x around 0 18.8%
Taylor expanded in x around inf 18.7%
*-un-lft-identity18.7%
pow1/218.7%
pow-flip18.7%
metadata-eval18.7%
Applied egg-rr18.7%
*-lft-identity18.7%
Simplified18.7%
(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 53.4%
flip--53.6%
div-inv53.6%
add-sqr-sqrt53.6%
add-sqr-sqrt54.5%
associate--l+54.5%
Applied egg-rr54.5%
associate-*r/54.5%
*-rgt-identity54.5%
+-commutative54.5%
associate-+l-99.7%
+-inverses99.7%
metadata-eval99.7%
+-commutative99.7%
+-commutative99.7%
Simplified99.7%
Taylor expanded in x around 0 59.1%
Taylor expanded in x around inf 12.7%
*-un-lft-identity12.7%
pow1/212.7%
pow-flip12.7%
metadata-eval12.7%
Applied egg-rr12.7%
*-lft-identity12.7%
Simplified12.7%
(FPCore (x) :precision binary64 (- (sqrt x)))
double code(double x) {
return -sqrt(x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = -sqrt(x)
end function
public static double code(double x) {
return -Math.sqrt(x);
}
def code(x): return -math.sqrt(x)
function code(x) return Float64(-sqrt(x)) end
function tmp = code(x) tmp = -sqrt(x); end
code[x_] := (-N[Sqrt[x], $MachinePrecision])
\begin{array}{l}
\\
-\sqrt{x}
\end{array}
Initial program 53.4%
Taylor expanded in x around 0 50.6%
Taylor expanded in x around inf 1.7%
neg-mul-11.7%
Simplified1.7%
(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 2024087
(FPCore (x)
:name "Main:bigenough3 from C"
:precision binary64
:alt
(/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x)))
(- (sqrt (+ x 1.0)) (sqrt x)))