
(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
(*
eps
(+
(+
1.0
(*
eps
(fma
eps
(-
(+ 0.3333333333333333 (pow (tan x) 4.0))
(* (pow (tan x) 2.0) -1.3333333333333333))
(+ (tan x) (pow (tan x) 3.0)))))
(/ (pow (sin x) 2.0) (pow (cos x) 2.0)))))
double code(double x, double eps) {
return eps * ((1.0 + (eps * fma(eps, ((0.3333333333333333 + pow(tan(x), 4.0)) - (pow(tan(x), 2.0) * -1.3333333333333333)), (tan(x) + pow(tan(x), 3.0))))) + (pow(sin(x), 2.0) / pow(cos(x), 2.0)));
}
function code(x, eps) return Float64(eps * Float64(Float64(1.0 + Float64(eps * fma(eps, Float64(Float64(0.3333333333333333 + (tan(x) ^ 4.0)) - Float64((tan(x) ^ 2.0) * -1.3333333333333333)), Float64(tan(x) + (tan(x) ^ 3.0))))) + Float64((sin(x) ^ 2.0) / (cos(x) ^ 2.0)))) end
code[x_, eps_] := N[(eps * N[(N[(1.0 + N[(eps * N[(eps * N[(N[(0.3333333333333333 + N[Power[N[Tan[x], $MachinePrecision], 4.0], $MachinePrecision]), $MachinePrecision] - N[(N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision] * -1.3333333333333333), $MachinePrecision]), $MachinePrecision] + N[(N[Tan[x], $MachinePrecision] + N[Power[N[Tan[x], $MachinePrecision], 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \left(0.3333333333333333 + {\tan x}^{4}\right) - {\tan x}^{2} \cdot -1.3333333333333333, \tan x + {\tan x}^{3}\right)\right) + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)
\end{array}
Initial program 61.7%
tan-sum61.8%
clear-num61.4%
Applied egg-rr61.4%
Taylor expanded in eps around 0 99.6%
Applied egg-rr99.6%
unpow199.6%
*-rgt-identity99.6%
cancel-sign-sub-inv99.6%
distribute-lft-neg-in99.6%
Simplified99.6%
sub-neg99.6%
Applied egg-rr99.6%
sub-neg99.6%
fma-undefine99.6%
neg-mul-199.6%
associate-+r-99.6%
sub-neg99.6%
+-commutative99.6%
associate--r+99.6%
metadata-eval99.6%
pow-sqr99.6%
distribute-lft-neg-out99.6%
cancel-sign-sub99.6%
pow-sqr99.6%
metadata-eval99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (x eps)
:precision binary64
(*
eps
(+
(/ (pow (sin x) 2.0) (pow (cos x) 2.0))
(+
1.0
(* eps (fma eps 0.3333333333333333 (+ (tan x) (pow (tan x) 3.0))))))))
double code(double x, double eps) {
return eps * ((pow(sin(x), 2.0) / pow(cos(x), 2.0)) + (1.0 + (eps * fma(eps, 0.3333333333333333, (tan(x) + pow(tan(x), 3.0))))));
}
function code(x, eps) return Float64(eps * Float64(Float64((sin(x) ^ 2.0) / (cos(x) ^ 2.0)) + Float64(1.0 + Float64(eps * fma(eps, 0.3333333333333333, Float64(tan(x) + (tan(x) ^ 3.0))))))) end
code[x_, eps_] := N[(eps * N[(N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] + N[(1.0 + N[(eps * N[(eps * 0.3333333333333333 + N[(N[Tan[x], $MachinePrecision] + N[Power[N[Tan[x], $MachinePrecision], 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \left(1 + \varepsilon \cdot \mathsf{fma}\left(\varepsilon, 0.3333333333333333, \tan x + {\tan x}^{3}\right)\right)\right)
\end{array}
Initial program 61.7%
tan-sum61.8%
clear-num61.4%
Applied egg-rr61.4%
Taylor expanded in eps around 0 99.6%
Applied egg-rr99.6%
unpow199.6%
*-rgt-identity99.6%
cancel-sign-sub-inv99.6%
distribute-lft-neg-in99.6%
Simplified99.6%
Taylor expanded in x around 0 99.5%
Final simplification99.5%
(FPCore (x eps) :precision binary64 (* eps (+ 1.0 (/ (pow (sin x) 2.0) (pow (cos x) 2.0)))))
double code(double x, double eps) {
return eps * (1.0 + (pow(sin(x), 2.0) / pow(cos(x), 2.0)));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * (1.0d0 + ((sin(x) ** 2.0d0) / (cos(x) ** 2.0d0)))
end function
public static double code(double x, double eps) {
return eps * (1.0 + (Math.pow(Math.sin(x), 2.0) / Math.pow(Math.cos(x), 2.0)));
}
def code(x, eps): return eps * (1.0 + (math.pow(math.sin(x), 2.0) / math.pow(math.cos(x), 2.0)))
function code(x, eps) return Float64(eps * Float64(1.0 + Float64((sin(x) ^ 2.0) / (cos(x) ^ 2.0)))) end
function tmp = code(x, eps) tmp = eps * (1.0 + ((sin(x) ^ 2.0) / (cos(x) ^ 2.0))); end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)
\end{array}
Initial program 61.7%
Taylor expanded in eps around 0 99.0%
sub-neg99.0%
mul-1-neg99.0%
remove-double-neg99.0%
Simplified99.0%
(FPCore (x eps)
:precision binary64
(+
(* eps (+ 1.0 (* 0.3333333333333333 (pow eps 2.0))))
(*
x
(+
(pow eps 2.0)
(* eps (* x (+ 1.0 (* (pow eps 2.0) 1.3333333333333333))))))))
double code(double x, double eps) {
return (eps * (1.0 + (0.3333333333333333 * pow(eps, 2.0)))) + (x * (pow(eps, 2.0) + (eps * (x * (1.0 + (pow(eps, 2.0) * 1.3333333333333333))))));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = (eps * (1.0d0 + (0.3333333333333333d0 * (eps ** 2.0d0)))) + (x * ((eps ** 2.0d0) + (eps * (x * (1.0d0 + ((eps ** 2.0d0) * 1.3333333333333333d0))))))
end function
public static double code(double x, double eps) {
return (eps * (1.0 + (0.3333333333333333 * Math.pow(eps, 2.0)))) + (x * (Math.pow(eps, 2.0) + (eps * (x * (1.0 + (Math.pow(eps, 2.0) * 1.3333333333333333))))));
}
def code(x, eps): return (eps * (1.0 + (0.3333333333333333 * math.pow(eps, 2.0)))) + (x * (math.pow(eps, 2.0) + (eps * (x * (1.0 + (math.pow(eps, 2.0) * 1.3333333333333333))))))
function code(x, eps) return Float64(Float64(eps * Float64(1.0 + Float64(0.3333333333333333 * (eps ^ 2.0)))) + Float64(x * Float64((eps ^ 2.0) + Float64(eps * Float64(x * Float64(1.0 + Float64((eps ^ 2.0) * 1.3333333333333333))))))) end
function tmp = code(x, eps) tmp = (eps * (1.0 + (0.3333333333333333 * (eps ^ 2.0)))) + (x * ((eps ^ 2.0) + (eps * (x * (1.0 + ((eps ^ 2.0) * 1.3333333333333333)))))); end
code[x_, eps_] := N[(N[(eps * N[(1.0 + N[(0.3333333333333333 * N[Power[eps, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(x * N[(N[Power[eps, 2.0], $MachinePrecision] + N[(eps * N[(x * N[(1.0 + N[(N[Power[eps, 2.0], $MachinePrecision] * 1.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(1 + 0.3333333333333333 \cdot {\varepsilon}^{2}\right) + x \cdot \left({\varepsilon}^{2} + \varepsilon \cdot \left(x \cdot \left(1 + {\varepsilon}^{2} \cdot 1.3333333333333333\right)\right)\right)
\end{array}
Initial program 61.7%
Taylor expanded in eps around 0 99.6%
Taylor expanded in x around 0 97.8%
Final simplification97.8%
(FPCore (x eps)
:precision binary64
(*
eps
(+
1.0
(+
(* 0.3333333333333333 (pow eps 2.0))
(* x (+ eps (* x (+ 1.0 (* (pow eps 2.0) 1.3333333333333333)))))))))
double code(double x, double eps) {
return eps * (1.0 + ((0.3333333333333333 * pow(eps, 2.0)) + (x * (eps + (x * (1.0 + (pow(eps, 2.0) * 1.3333333333333333)))))));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * (1.0d0 + ((0.3333333333333333d0 * (eps ** 2.0d0)) + (x * (eps + (x * (1.0d0 + ((eps ** 2.0d0) * 1.3333333333333333d0)))))))
end function
public static double code(double x, double eps) {
return eps * (1.0 + ((0.3333333333333333 * Math.pow(eps, 2.0)) + (x * (eps + (x * (1.0 + (Math.pow(eps, 2.0) * 1.3333333333333333)))))));
}
def code(x, eps): return eps * (1.0 + ((0.3333333333333333 * math.pow(eps, 2.0)) + (x * (eps + (x * (1.0 + (math.pow(eps, 2.0) * 1.3333333333333333)))))))
function code(x, eps) return Float64(eps * Float64(1.0 + Float64(Float64(0.3333333333333333 * (eps ^ 2.0)) + Float64(x * Float64(eps + Float64(x * Float64(1.0 + Float64((eps ^ 2.0) * 1.3333333333333333)))))))) end
function tmp = code(x, eps) tmp = eps * (1.0 + ((0.3333333333333333 * (eps ^ 2.0)) + (x * (eps + (x * (1.0 + ((eps ^ 2.0) * 1.3333333333333333))))))); end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[(0.3333333333333333 * N[Power[eps, 2.0], $MachinePrecision]), $MachinePrecision] + N[(x * N[(eps + N[(x * N[(1.0 + N[(N[Power[eps, 2.0], $MachinePrecision] * 1.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(1 + \left(0.3333333333333333 \cdot {\varepsilon}^{2} + x \cdot \left(\varepsilon + x \cdot \left(1 + {\varepsilon}^{2} \cdot 1.3333333333333333\right)\right)\right)\right)
\end{array}
Initial program 61.7%
Taylor expanded in eps around 0 99.6%
Taylor expanded in x around 0 97.8%
Final simplification97.8%
(FPCore (x eps) :precision binary64 (/ (sin eps) (cos eps)))
double code(double x, double eps) {
return sin(eps) / cos(eps);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = sin(eps) / cos(eps)
end function
public static double code(double x, double eps) {
return Math.sin(eps) / Math.cos(eps);
}
def code(x, eps): return math.sin(eps) / math.cos(eps)
function code(x, eps) return Float64(sin(eps) / cos(eps)) end
function tmp = code(x, eps) tmp = sin(eps) / cos(eps); end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[Cos[eps], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sin \varepsilon}{\cos \varepsilon}
\end{array}
Initial program 61.7%
Taylor expanded in x around 0 97.4%
(FPCore (x eps) :precision binary64 (+ eps (* 0.3333333333333333 (pow eps 3.0))))
double code(double x, double eps) {
return eps + (0.3333333333333333 * pow(eps, 3.0));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps + (0.3333333333333333d0 * (eps ** 3.0d0))
end function
public static double code(double x, double eps) {
return eps + (0.3333333333333333 * Math.pow(eps, 3.0));
}
def code(x, eps): return eps + (0.3333333333333333 * math.pow(eps, 3.0))
function code(x, eps) return Float64(eps + Float64(0.3333333333333333 * (eps ^ 3.0))) end
function tmp = code(x, eps) tmp = eps + (0.3333333333333333 * (eps ^ 3.0)); end
code[x_, eps_] := N[(eps + N[(0.3333333333333333 * N[Power[eps, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon + 0.3333333333333333 \cdot {\varepsilon}^{3}
\end{array}
Initial program 61.7%
Taylor expanded in eps around 0 99.6%
Taylor expanded in x around 0 97.4%
distribute-rgt-in97.4%
*-lft-identity97.4%
associate-*l*97.4%
unpow297.4%
unpow397.4%
Simplified97.4%
(FPCore (x eps) :precision binary64 (- (tan (+ eps x)) x))
double code(double x, double eps) {
return tan((eps + x)) - x;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = tan((eps + x)) - x
end function
public static double code(double x, double eps) {
return Math.tan((eps + x)) - x;
}
def code(x, eps): return math.tan((eps + x)) - x
function code(x, eps) return Float64(tan(Float64(eps + x)) - x) end
function tmp = code(x, eps) tmp = tan((eps + x)) - x; end
code[x_, eps_] := N[(N[Tan[N[(eps + x), $MachinePrecision]], $MachinePrecision] - x), $MachinePrecision]
\begin{array}{l}
\\
\tan \left(\varepsilon + x\right) - x
\end{array}
Initial program 61.7%
Taylor expanded in x around 0 59.9%
Final simplification59.9%
(FPCore (x eps) :precision binary64 (- x))
double code(double x, double eps) {
return -x;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = -x
end function
public static double code(double x, double eps) {
return -x;
}
def code(x, eps): return -x
function code(x, eps) return Float64(-x) end
function tmp = code(x, eps) tmp = -x; end
code[x_, eps_] := (-x)
\begin{array}{l}
\\
-x
\end{array}
Initial program 61.7%
Taylor expanded in x around 0 59.9%
Taylor expanded in x around inf 8.0%
neg-mul-18.0%
Simplified8.0%
(FPCore (x eps) :precision binary64 (/ (sin eps) (* (cos x) (cos (+ x eps)))))
double code(double x, double eps) {
return sin(eps) / (cos(x) * cos((x + eps)));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = sin(eps) / (cos(x) * cos((x + eps)))
end function
public static double code(double x, double eps) {
return Math.sin(eps) / (Math.cos(x) * Math.cos((x + eps)));
}
def code(x, eps): return math.sin(eps) / (math.cos(x) * math.cos((x + eps)))
function code(x, eps) return Float64(sin(eps) / Float64(cos(x) * cos(Float64(x + eps)))) end
function tmp = code(x, eps) tmp = sin(eps) / (cos(x) * cos((x + eps))); end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[x], $MachinePrecision] * N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \varepsilon\right)}
\end{array}
herbie shell --seed 2024111
(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
(/ (sin eps) (* (cos x) (cos (+ x eps))))
(- (tan (+ x eps)) (tan x)))