
(FPCore (x eps) :precision binary64 (- (cos (+ x eps)) (cos x)))
double code(double x, double eps) {
return cos((x + eps)) - cos(x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = cos((x + eps)) - cos(x)
end function
public static double code(double x, double eps) {
return Math.cos((x + eps)) - Math.cos(x);
}
def code(x, eps): return math.cos((x + eps)) - math.cos(x)
function code(x, eps) return Float64(cos(Float64(x + eps)) - cos(x)) end
function tmp = code(x, eps) tmp = cos((x + eps)) - cos(x); end
code[x_, eps_] := N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\cos \left(x + \varepsilon\right) - \cos x
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x eps) :precision binary64 (- (cos (+ x eps)) (cos x)))
double code(double x, double eps) {
return cos((x + eps)) - cos(x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = cos((x + eps)) - cos(x)
end function
public static double code(double x, double eps) {
return Math.cos((x + eps)) - Math.cos(x);
}
def code(x, eps): return math.cos((x + eps)) - math.cos(x)
function code(x, eps) return Float64(cos(Float64(x + eps)) - cos(x)) end
function tmp = code(x, eps) tmp = cos((x + eps)) - cos(x); end
code[x_, eps_] := N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\cos \left(x + \varepsilon\right) - \cos x
\end{array}
(FPCore (x eps) :precision binary64 (let* ((t_0 (sin (* 0.5 eps)))) (* (* (fma t_0 (cos x) (* (cos (* 0.5 eps)) (sin x))) t_0) -2.0)))
double code(double x, double eps) {
double t_0 = sin((0.5 * eps));
return (fma(t_0, cos(x), (cos((0.5 * eps)) * sin(x))) * t_0) * -2.0;
}
function code(x, eps) t_0 = sin(Float64(0.5 * eps)) return Float64(Float64(fma(t_0, cos(x), Float64(cos(Float64(0.5 * eps)) * sin(x))) * t_0) * -2.0) end
code[x_, eps_] := Block[{t$95$0 = N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(t$95$0 * N[Cos[x], $MachinePrecision] + N[(N[Cos[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision] * -2.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(0.5 \cdot \varepsilon\right)\\
\left(\mathsf{fma}\left(t\_0, \cos x, \cos \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right) \cdot t\_0\right) \cdot -2
\end{array}
\end{array}
Initial program 49.1%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites78.4%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
distribute-rgt-inN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
*-rgt-identityN/A
*-commutativeN/A
lower-sin.f64N/A
+-commutativeN/A
lower-fma.f64N/A
lower-sin.f64N/A
lower-*.f6499.7
Applied rewrites99.7%
Applied rewrites99.7%
(FPCore (x eps) :precision binary64 (* (* (sin (fma 0.5 eps x)) (sin (* 0.5 eps))) -2.0))
double code(double x, double eps) {
return (sin(fma(0.5, eps, x)) * sin((0.5 * eps))) * -2.0;
}
function code(x, eps) return Float64(Float64(sin(fma(0.5, eps, x)) * sin(Float64(0.5 * eps))) * -2.0) end
code[x_, eps_] := N[(N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
\begin{array}{l}
\\
\left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot -2
\end{array}
Initial program 49.1%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites78.4%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
distribute-rgt-inN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
*-rgt-identityN/A
*-commutativeN/A
lower-sin.f64N/A
+-commutativeN/A
lower-fma.f64N/A
lower-sin.f64N/A
lower-*.f6499.7
Applied rewrites99.7%
(FPCore (x eps) :precision binary64 (* (fma (* (cos x) eps) 0.5 (sin x)) (- eps)))
double code(double x, double eps) {
return fma((cos(x) * eps), 0.5, sin(x)) * -eps;
}
function code(x, eps) return Float64(fma(Float64(cos(x) * eps), 0.5, sin(x)) * Float64(-eps)) end
code[x_, eps_] := N[(N[(N[(N[Cos[x], $MachinePrecision] * eps), $MachinePrecision] * 0.5 + N[Sin[x], $MachinePrecision]), $MachinePrecision] * (-eps)), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\cos x \cdot \varepsilon, 0.5, \sin x\right) \cdot \left(-\varepsilon\right)
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
remove-double-negN/A
distribute-lft-neg-outN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f64N/A
Applied rewrites99.1%
(FPCore (x eps)
:precision binary64
(*
(-
(fma
(fma
(* (* (- (* 0.041666666666666664 (* eps eps)) 0.5) eps) x)
-0.5
(* (* eps eps) 0.16666666666666666))
x
(* -0.5 eps))
(sin x))
eps))
double code(double x, double eps) {
return (fma(fma(((((0.041666666666666664 * (eps * eps)) - 0.5) * eps) * x), -0.5, ((eps * eps) * 0.16666666666666666)), x, (-0.5 * eps)) - sin(x)) * eps;
}
function code(x, eps) return Float64(Float64(fma(fma(Float64(Float64(Float64(Float64(0.041666666666666664 * Float64(eps * eps)) - 0.5) * eps) * x), -0.5, Float64(Float64(eps * eps) * 0.16666666666666666)), x, Float64(-0.5 * eps)) - sin(x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(N[(N[(N[(0.041666666666666664 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] * eps), $MachinePrecision] * x), $MachinePrecision] * -0.5 + N[(N[(eps * eps), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]), $MachinePrecision] * x + N[(-0.5 * eps), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(0.041666666666666664 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \cdot \varepsilon\right) \cdot x, -0.5, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.16666666666666666\right), x, -0.5 \cdot \varepsilon\right) - \sin x\right) \cdot \varepsilon
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.6%
Taylor expanded in x around 0
Applied rewrites98.4%
Taylor expanded in eps around 0
Applied rewrites98.4%
(FPCore (x eps) :precision binary64 (* (- (* (fma (* 0.16666666666666666 eps) x (- (* 0.25 (* x x)) 0.5)) eps) (sin x)) eps))
double code(double x, double eps) {
return ((fma((0.16666666666666666 * eps), x, ((0.25 * (x * x)) - 0.5)) * eps) - sin(x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(fma(Float64(0.16666666666666666 * eps), x, Float64(Float64(0.25 * Float64(x * x)) - 0.5)) * eps) - sin(x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.16666666666666666 * eps), $MachinePrecision] * x + N[(N[(0.25 * N[(x * x), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(0.16666666666666666 \cdot \varepsilon, x, 0.25 \cdot \left(x \cdot x\right) - 0.5\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.6%
Taylor expanded in x around 0
Applied rewrites98.4%
Taylor expanded in eps around 0
Applied rewrites98.4%
(FPCore (x eps) :precision binary64 (* (- (* -0.5 eps) (sin x)) eps))
double code(double x, double eps) {
return ((-0.5 * eps) - sin(x)) * eps;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = (((-0.5d0) * eps) - sin(x)) * eps
end function
public static double code(double x, double eps) {
return ((-0.5 * eps) - Math.sin(x)) * eps;
}
def code(x, eps): return ((-0.5 * eps) - math.sin(x)) * eps
function code(x, eps) return Float64(Float64(Float64(-0.5 * eps) - sin(x)) * eps) end
function tmp = code(x, eps) tmp = ((-0.5 * eps) - sin(x)) * eps; end
code[x_, eps_] := N[(N[(N[(-0.5 * eps), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(-0.5 \cdot \varepsilon - \sin x\right) \cdot \varepsilon
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.6%
Taylor expanded in x around 0
Applied rewrites98.3%
Taylor expanded in eps around 0
Applied rewrites98.3%
(FPCore (x eps) :precision binary64 (* (fma (fma (fma -0.25 eps (* -0.16666666666666666 x)) x 1.0) x (* 0.5 eps)) (- eps)))
double code(double x, double eps) {
return fma(fma(fma(-0.25, eps, (-0.16666666666666666 * x)), x, 1.0), x, (0.5 * eps)) * -eps;
}
function code(x, eps) return Float64(fma(fma(fma(-0.25, eps, Float64(-0.16666666666666666 * x)), x, 1.0), x, Float64(0.5 * eps)) * Float64(-eps)) end
code[x_, eps_] := N[(N[(N[(N[(-0.25 * eps + N[(-0.16666666666666666 * x), $MachinePrecision]), $MachinePrecision] * x + 1.0), $MachinePrecision] * x + N[(0.5 * eps), $MachinePrecision]), $MachinePrecision] * (-eps)), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.25, \varepsilon, -0.16666666666666666 \cdot x\right), x, 1\right), x, 0.5 \cdot \varepsilon\right) \cdot \left(-\varepsilon\right)
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
remove-double-negN/A
distribute-lft-neg-outN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f64N/A
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites97.2%
(FPCore (x eps) :precision binary64 (fma (- eps) x (* (* eps eps) -0.5)))
double code(double x, double eps) {
return fma(-eps, x, ((eps * eps) * -0.5));
}
function code(x, eps) return fma(Float64(-eps), x, Float64(Float64(eps * eps) * -0.5)) end
code[x_, eps_] := N[((-eps) * x + N[(N[(eps * eps), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(-\varepsilon, x, \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right)
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
remove-double-negN/A
distribute-lft-neg-outN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f64N/A
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites96.4%
(FPCore (x eps) :precision binary64 (* (fma 0.5 eps x) (- eps)))
double code(double x, double eps) {
return fma(0.5, eps, x) * -eps;
}
function code(x, eps) return Float64(fma(0.5, eps, x) * Float64(-eps)) end
code[x_, eps_] := N[(N[(0.5 * eps + x), $MachinePrecision] * (-eps)), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(0.5, \varepsilon, x\right) \cdot \left(-\varepsilon\right)
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
remove-double-negN/A
distribute-lft-neg-outN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f64N/A
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites96.2%
(FPCore (x eps) :precision binary64 (* (- eps) x))
double code(double x, double eps) {
return -eps * x;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = -eps * x
end function
public static double code(double x, double eps) {
return -eps * x;
}
def code(x, eps): return -eps * x
function code(x, eps) return Float64(Float64(-eps) * x) end
function tmp = code(x, eps) tmp = -eps * x; end
code[x_, eps_] := N[((-eps) * x), $MachinePrecision]
\begin{array}{l}
\\
\left(-\varepsilon\right) \cdot x
\end{array}
Initial program 49.1%
Taylor expanded in eps around 0
associate-*r*N/A
mul-1-negN/A
lower-*.f64N/A
lower-neg.f64N/A
lower-sin.f6478.8
Applied rewrites78.8%
Taylor expanded in x around 0
Applied rewrites77.1%
(FPCore (x eps) :precision binary64 (- 1.0 1.0))
double code(double x, double eps) {
return 1.0 - 1.0;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = 1.0d0 - 1.0d0
end function
public static double code(double x, double eps) {
return 1.0 - 1.0;
}
def code(x, eps): return 1.0 - 1.0
function code(x, eps) return Float64(1.0 - 1.0) end
function tmp = code(x, eps) tmp = 1.0 - 1.0; end
code[x_, eps_] := N[(1.0 - 1.0), $MachinePrecision]
\begin{array}{l}
\\
1 - 1
\end{array}
Initial program 49.1%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6447.0
Applied rewrites47.0%
Taylor expanded in eps around 0
Applied rewrites46.9%
(FPCore (x eps) :precision binary64 (pow (cbrt (* (* -2.0 (sin (* 0.5 (fma 2.0 x eps)))) (sin (* 0.5 eps)))) 3.0))
double code(double x, double eps) {
return pow(cbrt(((-2.0 * sin((0.5 * fma(2.0, x, eps)))) * sin((0.5 * eps)))), 3.0);
}
function code(x, eps) return cbrt(Float64(Float64(-2.0 * sin(Float64(0.5 * fma(2.0, x, eps)))) * sin(Float64(0.5 * eps)))) ^ 3.0 end
code[x_, eps_] := N[Power[N[Power[N[(N[(-2.0 * N[Sin[N[(0.5 * N[(2.0 * x + eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision], 3.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\sqrt[3]{\left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)}\right)}^{3}
\end{array}
herbie shell --seed 2024337
(FPCore (x eps)
:name "2cos (problem 3.3.5)"
:precision binary64
:pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
:alt
(! :herbie-platform default (pow (cbrt (* -2 (sin (* 1/2 (fma 2 x eps))) (sin (* 1/2 eps)))) 3))
(- (cos (+ x eps)) (cos x)))