
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
return tan((x + eps)) - tan(x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps): return math.tan((x + eps)) - math.tan(x)
function code(x, eps) return Float64(tan(Float64(x + eps)) - tan(x)) end
function tmp = code(x, eps) tmp = tan((x + eps)) - tan(x); end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\tan \left(x + \varepsilon\right) - \tan x
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
return tan((x + eps)) - tan(x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps): return math.tan((x + eps)) - math.tan(x)
function code(x, eps) return Float64(tan(Float64(x + eps)) - tan(x)) end
function tmp = code(x, eps) tmp = tan((x + eps)) - tan(x); end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\tan \left(x + \varepsilon\right) - \tan x
\end{array}
(FPCore (x eps)
:precision binary64
(let* ((t_0 (pow (cos x) 2.0)) (t_1 (/ (pow (sin x) 2.0) t_0)))
(fma
(fma
(fma
(-
-0.16666666666666666
(-
(fma t_1 0.16666666666666666 (fma t_1 -0.5 -0.5))
(/ (fma (sin x) (sin x) (/ (pow (sin x) 4.0) t_0)) t_0)))
eps
(/ (+ (/ (pow (sin x) 3.0) t_0) (sin x)) (cos x)))
eps
t_1)
eps
eps)))
double code(double x, double eps) {
double t_0 = pow(cos(x), 2.0);
double t_1 = pow(sin(x), 2.0) / t_0;
return fma(fma(fma((-0.16666666666666666 - (fma(t_1, 0.16666666666666666, fma(t_1, -0.5, -0.5)) - (fma(sin(x), sin(x), (pow(sin(x), 4.0) / t_0)) / t_0))), eps, (((pow(sin(x), 3.0) / t_0) + sin(x)) / cos(x))), eps, t_1), eps, eps);
}
function code(x, eps) t_0 = cos(x) ^ 2.0 t_1 = Float64((sin(x) ^ 2.0) / t_0) return fma(fma(fma(Float64(-0.16666666666666666 - Float64(fma(t_1, 0.16666666666666666, fma(t_1, -0.5, -0.5)) - Float64(fma(sin(x), sin(x), Float64((sin(x) ^ 4.0) / t_0)) / t_0))), eps, Float64(Float64(Float64((sin(x) ^ 3.0) / t_0) + sin(x)) / cos(x))), eps, t_1), eps, eps) end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / t$95$0), $MachinePrecision]}, N[(N[(N[(N[(-0.16666666666666666 - N[(N[(t$95$1 * 0.16666666666666666 + N[(t$95$1 * -0.5 + -0.5), $MachinePrecision]), $MachinePrecision] - N[(N[(N[Sin[x], $MachinePrecision] * N[Sin[x], $MachinePrecision] + N[(N[Power[N[Sin[x], $MachinePrecision], 4.0], $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps + N[(N[(N[(N[Power[N[Sin[x], $MachinePrecision], 3.0], $MachinePrecision] / t$95$0), $MachinePrecision] + N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps + t$95$1), $MachinePrecision] * eps + eps), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := {\cos x}^{2}\\
t_1 := \frac{{\sin x}^{2}}{t\_0}\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666 - \left(\mathsf{fma}\left(t\_1, 0.16666666666666666, \mathsf{fma}\left(t\_1, -0.5, -0.5\right)\right) - \frac{\mathsf{fma}\left(\sin x, \sin x, \frac{{\sin x}^{4}}{t\_0}\right)}{t\_0}\right), \varepsilon, \frac{\frac{{\sin x}^{3}}{t\_0} + \sin x}{\cos x}\right), \varepsilon, t\_1\right), \varepsilon, \varepsilon\right)
\end{array}
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
Applied rewrites99.8%
(FPCore (x eps)
:precision binary64
(+
(fma
(* (tan x) eps)
(tan x)
(*
(*
(fma
eps
0.3333333333333333
(/ (* (fma (tan x) (tan x) 1.0) (sin x)) (cos x)))
eps)
eps))
eps))
double code(double x, double eps) {
return fma((tan(x) * eps), tan(x), ((fma(eps, 0.3333333333333333, ((fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))) * eps) * eps)) + eps;
}
function code(x, eps) return Float64(fma(Float64(tan(x) * eps), tan(x), Float64(Float64(fma(eps, 0.3333333333333333, Float64(Float64(fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))) * eps) * eps)) + eps) end
code[x_, eps_] := N[(N[(N[(N[Tan[x], $MachinePrecision] * eps), $MachinePrecision] * N[Tan[x], $MachinePrecision] + N[(N[(N[(eps * 0.3333333333333333 + N[(N[(N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision] * eps), $MachinePrecision]), $MachinePrecision] + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\tan x \cdot \varepsilon, \tan x, \left(\mathsf{fma}\left(\varepsilon, 0.3333333333333333, \frac{\mathsf{fma}\left(\tan x, \tan x, 1\right) \cdot \sin x}{\cos x}\right) \cdot \varepsilon\right) \cdot \varepsilon\right) + \varepsilon
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites99.7%
Applied rewrites99.7%
Applied rewrites99.8%
Final simplification99.8%
(FPCore (x eps)
:precision binary64
(+
(*
(fma
(fma
0.3333333333333333
eps
(/ (* (fma (tan x) (tan x) 1.0) (sin x)) (cos x)))
eps
(pow (tan x) 2.0))
eps)
eps))
double code(double x, double eps) {
return (fma(fma(0.3333333333333333, eps, ((fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))), eps, pow(tan(x), 2.0)) * eps) + eps;
}
function code(x, eps) return Float64(Float64(fma(fma(0.3333333333333333, eps, Float64(Float64(fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))), eps, (tan(x) ^ 2.0)) * eps) + eps) end
code[x_, eps_] := N[(N[(N[(N[(0.3333333333333333 * eps + N[(N[(N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps + N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision] + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, \varepsilon, \frac{\mathsf{fma}\left(\tan x, \tan x, 1\right) \cdot \sin x}{\cos x}\right), \varepsilon, {\tan x}^{2}\right) \cdot \varepsilon + \varepsilon
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites99.7%
Applied rewrites99.7%
Applied rewrites99.7%
(FPCore (x eps)
:precision binary64
(fma
(fma
(fma
eps
0.3333333333333333
(/ (* (fma (tan x) (tan x) 1.0) (sin x)) (cos x)))
eps
(pow (tan x) 2.0))
eps
eps))
double code(double x, double eps) {
return fma(fma(fma(eps, 0.3333333333333333, ((fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))), eps, pow(tan(x), 2.0)), eps, eps);
}
function code(x, eps) return fma(fma(fma(eps, 0.3333333333333333, Float64(Float64(fma(tan(x), tan(x), 1.0) * sin(x)) / cos(x))), eps, (tan(x) ^ 2.0)), eps, eps) end
code[x_, eps_] := N[(N[(N[(eps * 0.3333333333333333 + N[(N[(N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps + N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] * eps + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, 0.3333333333333333, \frac{\mathsf{fma}\left(\tan x, \tan x, 1\right) \cdot \sin x}{\cos x}\right), \varepsilon, {\tan x}^{2}\right), \varepsilon, \varepsilon\right)
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites99.7%
Applied rewrites99.7%
Applied rewrites99.7%
(FPCore (x eps)
:precision binary64
(fma
(fma
(fma
(fma (* 1.3333333333333333 (+ eps x)) x 1.0)
x
(* 0.3333333333333333 eps))
eps
(pow (tan x) 2.0))
eps
eps))
double code(double x, double eps) {
return fma(fma(fma(fma((1.3333333333333333 * (eps + x)), x, 1.0), x, (0.3333333333333333 * eps)), eps, pow(tan(x), 2.0)), eps, eps);
}
function code(x, eps) return fma(fma(fma(fma(Float64(1.3333333333333333 * Float64(eps + x)), x, 1.0), x, Float64(0.3333333333333333 * eps)), eps, (tan(x) ^ 2.0)), eps, eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(1.3333333333333333 * N[(eps + x), $MachinePrecision]), $MachinePrecision] * x + 1.0), $MachinePrecision] * x + N[(0.3333333333333333 * eps), $MachinePrecision]), $MachinePrecision] * eps + N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] * eps + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(1.3333333333333333 \cdot \left(\varepsilon + x\right), x, 1\right), x, 0.3333333333333333 \cdot \varepsilon\right), \varepsilon, {\tan x}^{2}\right), \varepsilon, \varepsilon\right)
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites99.6%
Applied rewrites99.6%
Final simplification99.6%
(FPCore (x eps) :precision binary64 (+ (* (pow (tan x) 2.0) eps) eps))
double code(double x, double eps) {
return (pow(tan(x), 2.0) * eps) + eps;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = ((tan(x) ** 2.0d0) * eps) + eps
end function
public static double code(double x, double eps) {
return (Math.pow(Math.tan(x), 2.0) * eps) + eps;
}
def code(x, eps): return (math.pow(math.tan(x), 2.0) * eps) + eps
function code(x, eps) return Float64(Float64((tan(x) ^ 2.0) * eps) + eps) end
function tmp = code(x, eps) tmp = ((tan(x) ^ 2.0) * eps) + eps; end
code[x_, eps_] := N[(N[(N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision] * eps), $MachinePrecision] + eps), $MachinePrecision]
\begin{array}{l}
\\
{\tan x}^{2} \cdot \varepsilon + \varepsilon
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
sub-negN/A
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
lower-fma.f64N/A
mul-1-negN/A
remove-double-negN/A
lower-/.f64N/A
lower-pow.f64N/A
lower-sin.f64N/A
lower-pow.f64N/A
lower-cos.f6499.4
Applied rewrites99.4%
Applied rewrites99.4%
Applied rewrites99.4%
(FPCore (x eps) :precision binary64 (fma (pow (tan x) 2.0) eps eps))
double code(double x, double eps) {
return fma(pow(tan(x), 2.0), eps, eps);
}
function code(x, eps) return fma((tan(x) ^ 2.0), eps, eps) end
code[x_, eps_] := N[(N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision] * eps + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left({\tan x}^{2}, \varepsilon, \varepsilon\right)
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
sub-negN/A
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
lower-fma.f64N/A
mul-1-negN/A
remove-double-negN/A
lower-/.f64N/A
lower-pow.f64N/A
lower-sin.f64N/A
lower-pow.f64N/A
lower-cos.f6499.4
Applied rewrites99.4%
Applied rewrites99.4%
(FPCore (x eps) :precision binary64 (fma (* (* (fma 0.6666666666666666 (* x x) 1.0) x) x) eps eps))
double code(double x, double eps) {
return fma(((fma(0.6666666666666666, (x * x), 1.0) * x) * x), eps, eps);
}
function code(x, eps) return fma(Float64(Float64(fma(0.6666666666666666, Float64(x * x), 1.0) * x) * x), eps, eps) end
code[x_, eps_] := N[(N[(N[(N[(0.6666666666666666 * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * eps + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 1\right) \cdot x\right) \cdot x, \varepsilon, \varepsilon\right)
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
sub-negN/A
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
lower-fma.f64N/A
mul-1-negN/A
remove-double-negN/A
lower-/.f64N/A
lower-pow.f64N/A
lower-sin.f64N/A
lower-pow.f64N/A
lower-cos.f6499.4
Applied rewrites99.4%
Taylor expanded in x around 0
Applied rewrites99.1%
(FPCore (x eps) :precision binary64 (fma (* x x) eps eps))
double code(double x, double eps) {
return fma((x * x), eps, eps);
}
function code(x, eps) return fma(Float64(x * x), eps, eps) end
code[x_, eps_] := N[(N[(x * x), $MachinePrecision] * eps + eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right)
\end{array}
Initial program 61.5%
Taylor expanded in eps around 0
sub-negN/A
+-commutativeN/A
distribute-rgt-inN/A
*-lft-identityN/A
lower-fma.f64N/A
mul-1-negN/A
remove-double-negN/A
lower-/.f64N/A
lower-pow.f64N/A
lower-sin.f64N/A
lower-pow.f64N/A
lower-cos.f6499.4
Applied rewrites99.4%
Taylor expanded in x around 0
Applied rewrites99.0%
(FPCore (x eps) :precision binary64 (+ eps (* (* eps (tan x)) (tan x))))
double code(double x, double eps) {
return eps + ((eps * tan(x)) * tan(x));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps + ((eps * tan(x)) * tan(x))
end function
public static double code(double x, double eps) {
return eps + ((eps * Math.tan(x)) * Math.tan(x));
}
def code(x, eps): return eps + ((eps * math.tan(x)) * math.tan(x))
function code(x, eps) return Float64(eps + Float64(Float64(eps * tan(x)) * tan(x))) end
function tmp = code(x, eps) tmp = eps + ((eps * tan(x)) * tan(x)); end
code[x_, eps_] := N[(eps + N[(N[(eps * N[Tan[x], $MachinePrecision]), $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x
\end{array}
herbie shell --seed 2024276
(FPCore (x eps)
:name "2tan (problem 3.3.2)"
:precision binary64
:pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
:alt
(! :herbie-platform default (+ eps (* eps (tan x) (tan x))))
(- (tan (+ x eps)) (tan x)))