
(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 (* -2.0 (* (sin (* 0.5 eps)) (sin (fma eps 0.5 x)))))
double code(double x, double eps) {
return -2.0 * (sin((0.5 * eps)) * sin(fma(eps, 0.5, x)));
}
function code(x, eps) return Float64(-2.0 * Float64(sin(Float64(0.5 * eps)) * sin(fma(eps, 0.5, x)))) end
code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision] * N[Sin[N[(eps * 0.5 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right)
\end{array}
Initial program 48.5%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around inf
*-commutativeN/A
metadata-evalN/A
cancel-sign-sub-invN/A
lower-*.f64N/A
lower-sin.f64N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-inN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-sin.f64N/A
*-commutativeN/A
lower-*.f6499.7
Applied rewrites99.7%
Final simplification99.7%
(FPCore (x eps)
:precision binary64
(*
(*
(*
(fma
(fma
(fma -1.5500992063492063e-6 (* eps eps) 0.00026041666666666666)
(* eps eps)
-0.020833333333333332)
(* eps eps)
0.5)
eps)
(sin (fma 0.5 eps x)))
-2.0))
double code(double x, double eps) {
return ((fma(fma(fma(-1.5500992063492063e-6, (eps * eps), 0.00026041666666666666), (eps * eps), -0.020833333333333332), (eps * eps), 0.5) * eps) * sin(fma(0.5, eps, x))) * -2.0;
}
function code(x, eps) return Float64(Float64(Float64(fma(fma(fma(-1.5500992063492063e-6, Float64(eps * eps), 0.00026041666666666666), Float64(eps * eps), -0.020833333333333332), Float64(eps * eps), 0.5) * eps) * sin(fma(0.5, eps, x))) * -2.0) end
code[x_, eps_] := N[(N[(N[(N[(N[(N[(-1.5500992063492063e-6 * N[(eps * eps), $MachinePrecision] + 0.00026041666666666666), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + 0.5), $MachinePrecision] * eps), $MachinePrecision] * N[Sin[N[(0.5 * eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-1.5500992063492063 \cdot 10^{-6}, \varepsilon \cdot \varepsilon, 0.00026041666666666666\right), \varepsilon \cdot \varepsilon, -0.020833333333333332\right), \varepsilon \cdot \varepsilon, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(0.5, \varepsilon, x\right)\right)\right) \cdot -2
\end{array}
Initial program 48.5%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
sub-negN/A
*-commutativeN/A
metadata-evalN/A
lower-fma.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6499.5
Applied rewrites99.5%
Taylor expanded in eps around 0
+-commutativeN/A
lower-fma.f6499.5
Applied rewrites99.5%
Final simplification99.5%
(FPCore (x eps)
:precision binary64
(*
(*
(*
(fma
(fma 0.00026041666666666666 (* eps eps) -0.020833333333333332)
(* eps eps)
0.5)
eps)
(sin (* (fma 2.0 x eps) 0.5)))
-2.0))
double code(double x, double eps) {
return ((fma(fma(0.00026041666666666666, (eps * eps), -0.020833333333333332), (eps * eps), 0.5) * eps) * sin((fma(2.0, x, eps) * 0.5))) * -2.0;
}
function code(x, eps) return Float64(Float64(Float64(fma(fma(0.00026041666666666666, Float64(eps * eps), -0.020833333333333332), Float64(eps * eps), 0.5) * eps) * sin(Float64(fma(2.0, x, eps) * 0.5))) * -2.0) end
code[x_, eps_] := N[(N[(N[(N[(N[(0.00026041666666666666 * N[(eps * eps), $MachinePrecision] + -0.020833333333333332), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + 0.5), $MachinePrecision] * eps), $MachinePrecision] * N[Sin[N[(N[(2.0 * x + eps), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.00026041666666666666, \varepsilon \cdot \varepsilon, -0.020833333333333332\right), \varepsilon \cdot \varepsilon, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2
\end{array}
Initial program 48.5%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
sub-negN/A
metadata-evalN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6499.3
Applied rewrites99.3%
Final simplification99.3%
(FPCore (x eps) :precision binary64 (* (* (* (fma (* eps eps) -0.020833333333333332 0.5) eps) (sin (* (fma 2.0 x eps) 0.5))) -2.0))
double code(double x, double eps) {
return ((fma((eps * eps), -0.020833333333333332, 0.5) * eps) * sin((fma(2.0, x, eps) * 0.5))) * -2.0;
}
function code(x, eps) return Float64(Float64(Float64(fma(Float64(eps * eps), -0.020833333333333332, 0.5) * eps) * sin(Float64(fma(2.0, x, eps) * 0.5))) * -2.0) end
code[x_, eps_] := N[(N[(N[(N[(N[(eps * eps), $MachinePrecision] * -0.020833333333333332 + 0.5), $MachinePrecision] * eps), $MachinePrecision] * N[Sin[N[(N[(2.0 * x + eps), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.020833333333333332, 0.5\right) \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2
\end{array}
Initial program 48.5%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6499.1
Applied rewrites99.1%
Final simplification99.1%
(FPCore (x eps) :precision binary64 (* (* (* 0.5 eps) (sin (* (fma 2.0 x eps) 0.5))) -2.0))
double code(double x, double eps) {
return ((0.5 * eps) * sin((fma(2.0, x, eps) * 0.5))) * -2.0;
}
function code(x, eps) return Float64(Float64(Float64(0.5 * eps) * sin(Float64(fma(2.0, x, eps) * 0.5))) * -2.0) end
code[x_, eps_] := N[(N[(N[(0.5 * eps), $MachinePrecision] * N[Sin[N[(N[(2.0 * x + eps), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\mathsf{fma}\left(2, x, \varepsilon\right) \cdot 0.5\right)\right) \cdot -2
\end{array}
Initial program 48.5%
lift--.f64N/A
lift-cos.f64N/A
lift-cos.f64N/A
diff-cosN/A
*-commutativeN/A
lower-*.f64N/A
Applied rewrites99.7%
Taylor expanded in eps around 0
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
Final simplification98.5%
(FPCore (x eps) :precision binary64 (* (fma (fma (* eps eps) 0.041666666666666664 -0.5) eps (- (sin x))) eps))
double code(double x, double eps) {
return fma(fma((eps * eps), 0.041666666666666664, -0.5), eps, -sin(x)) * eps;
}
function code(x, eps) return Float64(fma(fma(Float64(eps * eps), 0.041666666666666664, -0.5), eps, Float64(-sin(x))) * eps) end
code[x_, eps_] := N[(N[(N[(N[(eps * eps), $MachinePrecision] * 0.041666666666666664 + -0.5), $MachinePrecision] * eps + (-N[Sin[x], $MachinePrecision])), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.041666666666666664, -0.5\right), \varepsilon, -\sin x\right) \cdot \varepsilon
\end{array}
Initial program 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites98.1%
(FPCore (x eps)
:precision binary64
(let* ((t_0 (* (* (fma (* eps eps) 0.041666666666666664 -0.5) eps) eps)))
(fma
(fma
(fma
(* (fma -0.027777777777777776 (* eps eps) 0.16666666666666666) x)
eps
(* t_0 -0.5))
x
(* (fma (* 0.16666666666666666 eps) eps -1.0) eps))
x
t_0)))
double code(double x, double eps) {
double t_0 = (fma((eps * eps), 0.041666666666666664, -0.5) * eps) * eps;
return fma(fma(fma((fma(-0.027777777777777776, (eps * eps), 0.16666666666666666) * x), eps, (t_0 * -0.5)), x, (fma((0.16666666666666666 * eps), eps, -1.0) * eps)), x, t_0);
}
function code(x, eps) t_0 = Float64(Float64(fma(Float64(eps * eps), 0.041666666666666664, -0.5) * eps) * eps) return fma(fma(fma(Float64(fma(-0.027777777777777776, Float64(eps * eps), 0.16666666666666666) * x), eps, Float64(t_0 * -0.5)), x, Float64(fma(Float64(0.16666666666666666 * eps), eps, -1.0) * eps)), x, t_0) end
code[x_, eps_] := Block[{t$95$0 = N[(N[(N[(N[(eps * eps), $MachinePrecision] * 0.041666666666666664 + -0.5), $MachinePrecision] * eps), $MachinePrecision] * eps), $MachinePrecision]}, N[(N[(N[(N[(N[(-0.027777777777777776 * N[(eps * eps), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * eps + N[(t$95$0 * -0.5), $MachinePrecision]), $MachinePrecision] * x + N[(N[(N[(0.16666666666666666 * eps), $MachinePrecision] * eps + -1.0), $MachinePrecision] * eps), $MachinePrecision]), $MachinePrecision] * x + t$95$0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.041666666666666664, -0.5\right) \cdot \varepsilon\right) \cdot \varepsilon\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.027777777777777776, \varepsilon \cdot \varepsilon, 0.16666666666666666\right) \cdot x, \varepsilon, t\_0 \cdot -0.5\right), x, \mathsf{fma}\left(0.16666666666666666 \cdot \varepsilon, \varepsilon, -1\right) \cdot \varepsilon\right), x, t\_0\right)
\end{array}
\end{array}
Initial program 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites97.0%
Taylor expanded in x around 0
Applied rewrites98.0%
(FPCore (x eps)
:precision binary64
(let* ((t_0 (* (fma (* eps eps) 0.041666666666666664 -0.5) eps)))
(*
(fma
(fma
(fma
t_0
-0.5
(* (fma -0.027777777777777776 (* eps eps) 0.16666666666666666) x))
x
(fma (* 0.16666666666666666 eps) eps -1.0))
x
t_0)
eps)))
double code(double x, double eps) {
double t_0 = fma((eps * eps), 0.041666666666666664, -0.5) * eps;
return fma(fma(fma(t_0, -0.5, (fma(-0.027777777777777776, (eps * eps), 0.16666666666666666) * x)), x, fma((0.16666666666666666 * eps), eps, -1.0)), x, t_0) * eps;
}
function code(x, eps) t_0 = Float64(fma(Float64(eps * eps), 0.041666666666666664, -0.5) * eps) return Float64(fma(fma(fma(t_0, -0.5, Float64(fma(-0.027777777777777776, Float64(eps * eps), 0.16666666666666666) * x)), x, fma(Float64(0.16666666666666666 * eps), eps, -1.0)), x, t_0) * eps) end
code[x_, eps_] := Block[{t$95$0 = N[(N[(N[(eps * eps), $MachinePrecision] * 0.041666666666666664 + -0.5), $MachinePrecision] * eps), $MachinePrecision]}, N[(N[(N[(N[(t$95$0 * -0.5 + N[(N[(-0.027777777777777776 * N[(eps * eps), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * x + N[(N[(0.16666666666666666 * eps), $MachinePrecision] * eps + -1.0), $MachinePrecision]), $MachinePrecision] * x + t$95$0), $MachinePrecision] * eps), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.041666666666666664, -0.5\right) \cdot \varepsilon\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(t\_0, -0.5, \mathsf{fma}\left(-0.027777777777777776, \varepsilon \cdot \varepsilon, 0.16666666666666666\right) \cdot x\right), x, \mathsf{fma}\left(0.16666666666666666 \cdot \varepsilon, \varepsilon, -1\right)\right), x, t\_0\right) \cdot \varepsilon
\end{array}
\end{array}
Initial program 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites97.9%
(FPCore (x eps) :precision binary64 (* (fma (fma (* x eps) 0.16666666666666666 -0.5) eps (- x)) eps))
double code(double x, double eps) {
return fma(fma((x * eps), 0.16666666666666666, -0.5), eps, -x) * eps;
}
function code(x, eps) return Float64(fma(fma(Float64(x * eps), 0.16666666666666666, -0.5), eps, Float64(-x)) * eps) end
code[x_, eps_] := N[(N[(N[(N[(x * eps), $MachinePrecision] * 0.16666666666666666 + -0.5), $MachinePrecision] * eps + (-x)), $MachinePrecision] * eps), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(x \cdot \varepsilon, 0.16666666666666666, -0.5\right), \varepsilon, -x\right) \cdot \varepsilon
\end{array}
Initial program 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites97.0%
Taylor expanded in eps around 0
Applied rewrites97.0%
(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 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites99.1%
Taylor expanded in x around 0
Applied rewrites97.0%
Taylor expanded in eps around 0
Applied rewrites97.0%
(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 48.5%
Taylor expanded in eps around 0
mul-1-negN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f64N/A
lower-neg.f64N/A
lower-sin.f6475.2
Applied rewrites75.2%
Taylor expanded in x around 0
Applied rewrites74.6%
(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 48.5%
Taylor expanded in x around 0
lower--.f64N/A
lower-cos.f6446.3
Applied rewrites46.3%
Taylor expanded in eps around 0
Applied rewrites46.3%
(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 2024271
(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)))