
(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 12 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
(*
(-
(*
(fma
(cos x)
(fma eps (* 0.041666666666666664 eps) -0.5)
(* (* (sin x) eps) 0.16666666666666666))
eps)
(sin x))
eps))
double code(double x, double eps) {
return ((fma(cos(x), fma(eps, (0.041666666666666664 * eps), -0.5), ((sin(x) * eps) * 0.16666666666666666)) * eps) - sin(x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(fma(cos(x), fma(eps, Float64(0.041666666666666664 * eps), -0.5), Float64(Float64(sin(x) * eps) * 0.16666666666666666)) * eps) - sin(x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[Cos[x], $MachinePrecision] * N[(eps * N[(0.041666666666666664 * eps), $MachinePrecision] + -0.5), $MachinePrecision] + N[(N[(N[Sin[x], $MachinePrecision] * eps), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(\cos x, \mathsf{fma}\left(\varepsilon, 0.041666666666666664 \cdot \varepsilon, -0.5\right), \left(\sin x \cdot \varepsilon\right) \cdot 0.16666666666666666\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
(FPCore (x eps) :precision binary64 (* 2.0 (* (sin (fma 0.5 eps x)) (* (fma (* 0.020833333333333332 eps) eps -0.5) eps))))
double code(double x, double eps) {
return 2.0 * (sin(fma(0.5, eps, x)) * (fma((0.020833333333333332 * eps), eps, -0.5) * eps));
}
function code(x, eps) return Float64(2.0 * Float64(sin(fma(0.5, eps, x)) * Float64(fma(Float64(0.020833333333333332 * eps), eps, -0.5) * eps))) end
code[x_, eps_] := N[(2.0 * N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(0.020833333333333332 * eps), $MachinePrecision] * eps + -0.5), $MachinePrecision] * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(\mathsf{fma}\left(0.020833333333333332 \cdot \varepsilon, \varepsilon, -0.5\right) \cdot \varepsilon\right)\right)
\end{array}
Initial program 50.9%
lift--.f64N/A
lift-cos.f64N/A
sin-+PI/2-revN/A
lift-cos.f64N/A
cos-neg-revN/A
sin-+PI/2-revN/A
diff-sinN/A
lower-*.f64N/A
lower-*.f64N/A
Applied rewrites51.6%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f64N/A
lower-sin.f64N/A
distribute-lft-inN/A
associate-*r*N/A
metadata-evalN/A
*-lft-identityN/A
lower-fma.f64N/A
cos-neg-revN/A
lower-cos.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
+-commutativeN/A
lower-+.f64N/A
lower-PI.f647.5
Applied rewrites7.5%
Applied rewrites7.4%
Taylor expanded in eps around 0
Applied rewrites99.7%
(FPCore (x eps) :precision binary64 (* 2.0 (* (sin (fma 0.5 eps x)) (* -0.5 eps))))
double code(double x, double eps) {
return 2.0 * (sin(fma(0.5, eps, x)) * (-0.5 * eps));
}
function code(x, eps) return Float64(2.0 * Float64(sin(fma(0.5, eps, x)) * Float64(-0.5 * eps))) end
code[x_, eps_] := N[(2.0 * N[(N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision] * N[(-0.5 * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \left(\sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right) \cdot \left(-0.5 \cdot \varepsilon\right)\right)
\end{array}
Initial program 50.9%
lift--.f64N/A
lift-cos.f64N/A
sin-+PI/2-revN/A
lift-cos.f64N/A
cos-neg-revN/A
sin-+PI/2-revN/A
diff-sinN/A
lower-*.f64N/A
lower-*.f64N/A
Applied rewrites51.6%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f64N/A
lower-sin.f64N/A
distribute-lft-inN/A
associate-*r*N/A
metadata-evalN/A
*-lft-identityN/A
lower-fma.f64N/A
cos-neg-revN/A
lower-cos.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
+-commutativeN/A
lower-+.f64N/A
lower-PI.f647.5
Applied rewrites7.5%
Applied rewrites7.4%
Taylor expanded in eps around 0
Applied rewrites99.5%
(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 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
lower--.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sin.f64N/A
lower-*.f64N/A
lower-cos.f64N/A
lower-sin.f6499.6
Applied rewrites99.6%
Taylor expanded in x around 0
Applied rewrites99.3%
(FPCore (x eps)
:precision binary64
(*
(-
(* (- (* 0.041666666666666664 (* eps eps)) 0.5) eps)
(fma
(* x (* x x))
(- (* (* 0.008333333333333333 x) x) 0.16666666666666666)
x))
eps))
double code(double x, double eps) {
return ((((0.041666666666666664 * (eps * eps)) - 0.5) * eps) - fma((x * (x * x)), (((0.008333333333333333 * x) * x) - 0.16666666666666666), x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(Float64(Float64(0.041666666666666664 * Float64(eps * eps)) - 0.5) * eps) - fma(Float64(x * Float64(x * x)), Float64(Float64(Float64(0.008333333333333333 * x) * x) - 0.16666666666666666), x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.041666666666666664 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] * eps), $MachinePrecision] - N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(N[(N[(0.008333333333333333 * x), $MachinePrecision] * x), $MachinePrecision] - 0.16666666666666666), $MachinePrecision] + x), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(0.041666666666666664 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \cdot \varepsilon - \mathsf{fma}\left(x \cdot \left(x \cdot x\right), \left(0.008333333333333333 \cdot x\right) \cdot x - 0.16666666666666666, x\right)\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites99.3%
Taylor expanded in x around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites99.1%
(FPCore (x eps)
:precision binary64
(*
(-
(* (- (* 0.041666666666666664 (* eps eps)) 0.5) eps)
(*
(fma (- (* 0.008333333333333333 (* x x)) 0.16666666666666666) (* x x) 1.0)
x))
eps))
double code(double x, double eps) {
return ((((0.041666666666666664 * (eps * eps)) - 0.5) * eps) - (fma(((0.008333333333333333 * (x * x)) - 0.16666666666666666), (x * x), 1.0) * x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(Float64(Float64(0.041666666666666664 * Float64(eps * eps)) - 0.5) * eps) - Float64(fma(Float64(Float64(0.008333333333333333 * Float64(x * x)) - 0.16666666666666666), Float64(x * x), 1.0) * x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.041666666666666664 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] * eps), $MachinePrecision] - N[(N[(N[(N[(0.008333333333333333 * N[(x * x), $MachinePrecision]), $MachinePrecision] - 0.16666666666666666), $MachinePrecision] * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(0.041666666666666664 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \cdot \varepsilon - \mathsf{fma}\left(0.008333333333333333 \cdot \left(x \cdot x\right) - 0.16666666666666666, x \cdot x, 1\right) \cdot x\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites99.3%
Taylor expanded in x around 0
Applied rewrites99.1%
(FPCore (x eps) :precision binary64 (* (- (* (- (* 0.041666666666666664 (* eps eps)) 0.5) eps) (fma (* x (* x x)) -0.16666666666666666 x)) eps))
double code(double x, double eps) {
return ((((0.041666666666666664 * (eps * eps)) - 0.5) * eps) - fma((x * (x * x)), -0.16666666666666666, x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(Float64(Float64(0.041666666666666664 * Float64(eps * eps)) - 0.5) * eps) - fma(Float64(x * Float64(x * x)), -0.16666666666666666, x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.041666666666666664 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] * eps), $MachinePrecision] - N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * -0.16666666666666666 + x), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(0.041666666666666664 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \cdot \varepsilon - \mathsf{fma}\left(x \cdot \left(x \cdot x\right), -0.16666666666666666, x\right)\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites99.3%
Taylor expanded in x around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites99.1%
(FPCore (x eps) :precision binary64 (* (- (* (- (* 0.041666666666666664 (* eps eps)) 0.5) eps) (* (fma (* x x) -0.16666666666666666 1.0) x)) eps))
double code(double x, double eps) {
return ((((0.041666666666666664 * (eps * eps)) - 0.5) * eps) - (fma((x * x), -0.16666666666666666, 1.0) * x)) * eps;
}
function code(x, eps) return Float64(Float64(Float64(Float64(Float64(0.041666666666666664 * Float64(eps * eps)) - 0.5) * eps) - Float64(fma(Float64(x * x), -0.16666666666666666, 1.0) * x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.041666666666666664 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] * eps), $MachinePrecision] - N[(N[(N[(x * x), $MachinePrecision] * -0.16666666666666666 + 1.0), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(0.041666666666666664 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \cdot \varepsilon - \mathsf{fma}\left(x \cdot x, -0.16666666666666666, 1\right) \cdot x\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites99.3%
Taylor expanded in x around 0
Applied rewrites99.0%
(FPCore (x eps) :precision binary64 (* (fma (- (* (* 0.16666666666666666 x) eps) 0.5) eps (- x)) eps))
double code(double x, double eps) {
return fma((((0.16666666666666666 * x) * eps) - 0.5), eps, -x) * eps;
}
function code(x, eps) return Float64(fma(Float64(Float64(Float64(0.16666666666666666 * x) * eps) - 0.5), eps, Float64(-x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.16666666666666666 * x), $MachinePrecision] * eps), $MachinePrecision] - 0.5), $MachinePrecision] * eps + (-x)), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\left(0.16666666666666666 \cdot x\right) \cdot \varepsilon - 0.5, \varepsilon, -x\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites98.5%
Taylor expanded in eps around 0
Applied rewrites98.5%
(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, Float64(-x)) * 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 \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in x around 0
Applied rewrites98.5%
Taylor expanded in eps around 0
Applied rewrites98.5%
(FPCore (x eps) :precision binary64 (* (- x) eps))
double code(double x, double eps) {
return -x * eps;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = -x * eps
end function
public static double code(double x, double eps) {
return -x * eps;
}
def code(x, eps): return -x * eps
function code(x, eps) return Float64(Float64(-x) * eps) end
function tmp = code(x, eps) tmp = -x * eps; end
code[x_, eps_] := N[((-x) * eps), $MachinePrecision]
\begin{array}{l}
\\
\left(-x\right) \cdot \varepsilon
\end{array}
Initial program 50.9%
Taylor expanded in eps around 0
associate-*r*N/A
mul-1-negN/A
lower-*.f64N/A
lower-neg.f64N/A
lower-sin.f6480.6
Applied rewrites80.6%
Taylor expanded in x around 0
Applied rewrites80.2%
(FPCore (x eps) :precision binary64 (* 2.0 0.0))
double code(double x, double eps) {
return 2.0 * 0.0;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = 2.0d0 * 0.0d0
end function
public static double code(double x, double eps) {
return 2.0 * 0.0;
}
def code(x, eps): return 2.0 * 0.0
function code(x, eps) return Float64(2.0 * 0.0) end
function tmp = code(x, eps) tmp = 2.0 * 0.0; end
code[x_, eps_] := N[(2.0 * 0.0), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot 0
\end{array}
Initial program 50.9%
lift--.f64N/A
lift-cos.f64N/A
sin-+PI/2-revN/A
lift-cos.f64N/A
cos-neg-revN/A
sin-+PI/2-revN/A
diff-sinN/A
lower-*.f64N/A
lower-*.f64N/A
Applied rewrites51.6%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f64N/A
lower-sin.f64N/A
distribute-lft-inN/A
associate-*r*N/A
metadata-evalN/A
*-lft-identityN/A
lower-fma.f64N/A
cos-neg-revN/A
lower-cos.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
lower-*.f64N/A
+-commutativeN/A
lower-+.f64N/A
lower-PI.f647.5
Applied rewrites7.5%
Applied rewrites7.4%
Taylor expanded in eps around 0
Applied rewrites50.3%
(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 2024339
(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)))