
(FPCore (x) :precision binary64 (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
double t_0 = tan(x) * tan(x);
return (1.0 - t_0) / (1.0 + t_0);
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = tan(x) * tan(x)
code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
double t_0 = Math.tan(x) * Math.tan(x);
return (1.0 - t_0) / (1.0 + t_0);
}
def code(x): t_0 = math.tan(x) * math.tan(x) return (1.0 - t_0) / (1.0 + t_0)
function code(x) t_0 = Float64(tan(x) * tan(x)) return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) end
function tmp = code(x) t_0 = tan(x) * tan(x); tmp = (1.0 - t_0) / (1.0 + t_0); end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
double t_0 = tan(x) * tan(x);
return (1.0 - t_0) / (1.0 + t_0);
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = tan(x) * tan(x)
code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
double t_0 = Math.tan(x) * Math.tan(x);
return (1.0 - t_0) / (1.0 + t_0);
}
def code(x): t_0 = math.tan(x) * math.tan(x) return (1.0 - t_0) / (1.0 + t_0)
function code(x) t_0 = Float64(tan(x) * tan(x)) return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) end
function tmp = code(x) t_0 = tan(x) * tan(x); tmp = (1.0 - t_0) / (1.0 + t_0); end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}
(FPCore (x) :precision binary64 (/ (- 1.0 (pow (tan x) 2.0)) (fma (tan x) (tan x) 1.0)))
double code(double x) {
return (1.0 - pow(tan(x), 2.0)) / fma(tan(x), tan(x), 1.0);
}
function code(x) return Float64(Float64(1.0 - (tan(x) ^ 2.0)) / fma(tan(x), tan(x), 1.0)) end
code[x_] := N[(N[(1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] / N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1 - {\tan x}^{2}}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}
\end{array}
Initial program 99.6%
+-commutative99.6%
fma-def99.6%
Simplified99.6%
add-log-exp98.0%
*-un-lft-identity98.0%
log-prod98.0%
metadata-eval98.0%
add-log-exp99.6%
pow299.6%
Applied egg-rr99.6%
+-lft-identity99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (x) :precision binary64 (let* ((t_0 (pow (tan x) 2.0))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
double t_0 = pow(tan(x), 2.0);
return (1.0 - t_0) / (1.0 + t_0);
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
t_0 = tan(x) ** 2.0d0
code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
double t_0 = Math.pow(Math.tan(x), 2.0);
return (1.0 - t_0) / (1.0 + t_0);
}
def code(x): t_0 = math.pow(math.tan(x), 2.0) return (1.0 - t_0) / (1.0 + t_0)
function code(x) t_0 = tan(x) ^ 2.0 return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) end
function tmp = code(x) t_0 = tan(x) ^ 2.0; tmp = (1.0 - t_0) / (1.0 + t_0); end
code[x_] := Block[{t$95$0 = N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}
Initial program 99.6%
+-commutative99.6%
fma-def99.6%
Simplified99.6%
add-log-exp98.0%
*-un-lft-identity98.0%
log-prod98.0%
metadata-eval98.0%
add-log-exp99.6%
pow299.6%
Applied egg-rr99.6%
+-lft-identity99.6%
Simplified99.6%
fma-udef99.6%
pow299.6%
Applied egg-rr99.6%
Final simplification99.6%
(FPCore (x) :precision binary64 (if (<= (tan x) 1.0) (/ -1.0 (- -1.0 (pow (tan x) 2.0))) (/ (- 1.0 (* x x)) (+ 1.0 (* x x)))))
double code(double x) {
double tmp;
if (tan(x) <= 1.0) {
tmp = -1.0 / (-1.0 - pow(tan(x), 2.0));
} else {
tmp = (1.0 - (x * x)) / (1.0 + (x * x));
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (tan(x) <= 1.0d0) then
tmp = (-1.0d0) / ((-1.0d0) - (tan(x) ** 2.0d0))
else
tmp = (1.0d0 - (x * x)) / (1.0d0 + (x * x))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (Math.tan(x) <= 1.0) {
tmp = -1.0 / (-1.0 - Math.pow(Math.tan(x), 2.0));
} else {
tmp = (1.0 - (x * x)) / (1.0 + (x * x));
}
return tmp;
}
def code(x): tmp = 0 if math.tan(x) <= 1.0: tmp = -1.0 / (-1.0 - math.pow(math.tan(x), 2.0)) else: tmp = (1.0 - (x * x)) / (1.0 + (x * x)) return tmp
function code(x) tmp = 0.0 if (tan(x) <= 1.0) tmp = Float64(-1.0 / Float64(-1.0 - (tan(x) ^ 2.0))); else tmp = Float64(Float64(1.0 - Float64(x * x)) / Float64(1.0 + Float64(x * x))); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (tan(x) <= 1.0) tmp = -1.0 / (-1.0 - (tan(x) ^ 2.0)); else tmp = (1.0 - (x * x)) / (1.0 + (x * x)); end tmp_2 = tmp; end
code[x_] := If[LessEqual[N[Tan[x], $MachinePrecision], 1.0], N[(-1.0 / N[(-1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\tan x \leq 1:\\
\;\;\;\;\frac{-1}{-1 - {\tan x}^{2}}\\
\mathbf{else}:\\
\;\;\;\;\frac{1 - x \cdot x}{1 + x \cdot x}\\
\end{array}
\end{array}
if (tan.f64 x) < 1Initial program 99.6%
frac-2neg99.6%
div-inv99.6%
pow299.6%
+-commutative99.6%
distribute-neg-in99.6%
neg-mul-199.6%
metadata-eval99.6%
fma-def99.6%
pow299.6%
Applied egg-rr99.6%
associate-*r/99.6%
*-rgt-identity99.6%
neg-sub099.6%
associate--r-99.6%
metadata-eval99.6%
+-commutative99.6%
unpow299.6%
fma-udef99.6%
fma-udef99.6%
neg-mul-199.6%
+-commutative99.6%
unsub-neg99.6%
Simplified99.6%
Taylor expanded in x around 0 66.0%
if 1 < (tan.f64 x) Initial program 99.4%
Taylor expanded in x around 0 4.3%
unpow24.3%
Simplified4.3%
Taylor expanded in x around 0 13.7%
+-commutative13.7%
unpow213.7%
Simplified13.7%
Final simplification58.2%
(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 99.6%
Taylor expanded in x around 0 56.1%
Final simplification56.1%
herbie shell --seed 2023279
(FPCore (x)
:name "Trigonometry B"
:precision binary64
(/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))