
(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 6 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 (* (sin (* eps 0.5)) (* -2.0 (sin (* 0.5 (fma 2.0 x eps))))))
double code(double x, double eps) {
return sin((eps * 0.5)) * (-2.0 * sin((0.5 * fma(2.0, x, eps))));
}
function code(x, eps) return Float64(sin(Float64(eps * 0.5)) * Float64(-2.0 * sin(Float64(0.5 * fma(2.0, x, eps))))) end
code[x_, eps_] := N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(-2.0 * N[Sin[N[(0.5 * N[(2.0 * x + eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right)
\end{array}
Initial program 52.7%
diff-cos80.3%
div-inv80.3%
associate--l+80.3%
metadata-eval80.3%
div-inv80.3%
+-commutative80.3%
associate-+l+80.3%
metadata-eval80.3%
Applied egg-rr80.3%
associate-*r*80.3%
*-commutative80.3%
associate-*l*80.3%
sub-neg80.3%
mul-1-neg80.3%
+-commutative80.3%
associate-+r+99.7%
mul-1-neg99.7%
sub-neg99.7%
+-inverses99.7%
remove-double-neg99.7%
mul-1-neg99.7%
sub-neg99.7%
neg-sub099.7%
mul-1-neg99.7%
remove-double-neg99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (x eps) :precision binary64 (* -2.0 (* (sin (* eps 0.5)) (sin (* 0.5 (+ eps (+ x x)))))))
double code(double x, double eps) {
return -2.0 * (sin((eps * 0.5)) * sin((0.5 * (eps + (x + x)))));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = (-2.0d0) * (sin((eps * 0.5d0)) * sin((0.5d0 * (eps + (x + x)))))
end function
public static double code(double x, double eps) {
return -2.0 * (Math.sin((eps * 0.5)) * Math.sin((0.5 * (eps + (x + x)))));
}
def code(x, eps): return -2.0 * (math.sin((eps * 0.5)) * math.sin((0.5 * (eps + (x + x)))))
function code(x, eps) return Float64(-2.0 * Float64(sin(Float64(eps * 0.5)) * sin(Float64(0.5 * Float64(eps + Float64(x + x)))))) end
function tmp = code(x, eps) tmp = -2.0 * (sin((eps * 0.5)) * sin((0.5 * (eps + (x + x))))); end
code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Sin[N[(0.5 * N[(eps + N[(x + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)
\end{array}
Initial program 52.7%
diff-cos80.3%
*-commutative80.3%
div-inv80.3%
associate--l+80.3%
metadata-eval80.3%
div-inv80.3%
+-commutative80.3%
associate-+l+80.3%
metadata-eval80.3%
Applied egg-rr80.3%
Taylor expanded in x around 0 99.6%
Final simplification99.6%
(FPCore (x eps) :precision binary64 (fma (pow eps 2.0) -0.5 (* eps (- x))))
double code(double x, double eps) {
return fma(pow(eps, 2.0), -0.5, (eps * -x));
}
function code(x, eps) return fma((eps ^ 2.0), -0.5, Float64(eps * Float64(-x))) end
code[x_, eps_] := N[(N[Power[eps, 2.0], $MachinePrecision] * -0.5 + N[(eps * (-x)), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left({\varepsilon}^{2}, -0.5, \varepsilon \cdot \left(-x\right)\right)
\end{array}
Initial program 52.7%
Taylor expanded in eps around 0 99.3%
associate-+r+99.3%
+-commutative99.3%
associate-+l+99.3%
associate-*r*99.3%
*-commutative99.3%
associate-*r*99.3%
associate-*r*99.3%
distribute-rgt-out99.3%
mul-1-neg99.3%
Simplified99.3%
Taylor expanded in x around inf 99.3%
*-commutative99.3%
Simplified99.3%
Taylor expanded in x around 0 96.8%
+-commutative96.8%
*-commutative96.8%
fma-neg96.8%
fma-define97.0%
fma-neg97.0%
*-commutative97.0%
Simplified97.0%
Taylor expanded in eps around 0 96.8%
+-commutative96.8%
*-commutative96.8%
fma-define96.8%
associate-*r*96.8%
*-commutative96.8%
neg-mul-196.8%
Simplified96.8%
Final simplification96.8%
(FPCore (x eps) :precision binary64 (- (* (pow eps 2.0) -0.5) (* eps x)))
double code(double x, double eps) {
return (pow(eps, 2.0) * -0.5) - (eps * x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = ((eps ** 2.0d0) * (-0.5d0)) - (eps * x)
end function
public static double code(double x, double eps) {
return (Math.pow(eps, 2.0) * -0.5) - (eps * x);
}
def code(x, eps): return (math.pow(eps, 2.0) * -0.5) - (eps * x)
function code(x, eps) return Float64(Float64((eps ^ 2.0) * -0.5) - Float64(eps * x)) end
function tmp = code(x, eps) tmp = ((eps ^ 2.0) * -0.5) - (eps * x); end
code[x_, eps_] := N[(N[(N[Power[eps, 2.0], $MachinePrecision] * -0.5), $MachinePrecision] - N[(eps * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
{\varepsilon}^{2} \cdot -0.5 - \varepsilon \cdot x
\end{array}
Initial program 52.7%
diff-cos80.3%
div-inv80.3%
associate--l+80.3%
metadata-eval80.3%
div-inv80.3%
+-commutative80.3%
associate-+l+80.3%
metadata-eval80.3%
Applied egg-rr80.3%
associate-*r*80.3%
*-commutative80.3%
associate-*l*80.3%
sub-neg80.3%
mul-1-neg80.3%
+-commutative80.3%
associate-+r+99.7%
mul-1-neg99.7%
sub-neg99.7%
+-inverses99.7%
remove-double-neg99.7%
mul-1-neg99.7%
sub-neg99.7%
neg-sub099.7%
mul-1-neg99.7%
remove-double-neg99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
Taylor expanded in eps around 0 99.0%
+-commutative99.0%
*-commutative99.0%
fma-define99.0%
mul-1-neg99.0%
fma-neg99.0%
associate-*l*99.0%
*-commutative99.0%
Simplified99.0%
Taylor expanded in x around 0 96.8%
+-commutative96.8%
mul-1-neg96.8%
unsub-neg96.8%
*-commutative96.8%
Simplified96.8%
Final simplification96.8%
(FPCore (x eps) :precision binary64 (* eps (- (sin x))))
double code(double x, double eps) {
return eps * -sin(x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * -sin(x)
end function
public static double code(double x, double eps) {
return eps * -Math.sin(x);
}
def code(x, eps): return eps * -math.sin(x)
function code(x, eps) return Float64(eps * Float64(-sin(x))) end
function tmp = code(x, eps) tmp = eps * -sin(x); end
code[x_, eps_] := N[(eps * (-N[Sin[x], $MachinePrecision])), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(-\sin x\right)
\end{array}
Initial program 52.7%
Taylor expanded in eps around 0 79.7%
mul-1-neg79.7%
*-commutative79.7%
distribute-rgt-neg-in79.7%
Simplified79.7%
Final simplification79.7%
(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(eps * Float64(-x)) end
function tmp = code(x, eps) tmp = eps * -x; end
code[x_, eps_] := N[(eps * (-x)), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(-x\right)
\end{array}
Initial program 52.7%
diff-cos80.3%
*-commutative80.3%
div-inv80.3%
associate--l+80.3%
metadata-eval80.3%
div-inv80.3%
+-commutative80.3%
associate-+l+80.3%
metadata-eval80.3%
Applied egg-rr80.3%
Taylor expanded in eps around 0 79.7%
*-commutative79.7%
Simplified79.7%
Taylor expanded in x around 0 78.4%
mul-1-neg78.4%
distribute-rgt-neg-in78.4%
Simplified78.4%
Final simplification78.4%
(FPCore (x eps) :precision binary64 (* (* -2.0 (sin (+ x (/ eps 2.0)))) (sin (/ eps 2.0))))
double code(double x, double eps) {
return (-2.0 * sin((x + (eps / 2.0)))) * sin((eps / 2.0));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = ((-2.0d0) * sin((x + (eps / 2.0d0)))) * sin((eps / 2.0d0))
end function
public static double code(double x, double eps) {
return (-2.0 * Math.sin((x + (eps / 2.0)))) * Math.sin((eps / 2.0));
}
def code(x, eps): return (-2.0 * math.sin((x + (eps / 2.0)))) * math.sin((eps / 2.0))
function code(x, eps) return Float64(Float64(-2.0 * sin(Float64(x + Float64(eps / 2.0)))) * sin(Float64(eps / 2.0))) end
function tmp = code(x, eps) tmp = (-2.0 * sin((x + (eps / 2.0)))) * sin((eps / 2.0)); end
code[x_, eps_] := N[(N[(-2.0 * N[Sin[N[(x + N[(eps / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(eps / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(-2 \cdot \sin \left(x + \frac{\varepsilon}{2}\right)\right) \cdot \sin \left(\frac{\varepsilon}{2}\right)
\end{array}
herbie shell --seed 2024044
(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)))
:herbie-target
(* (* -2.0 (sin (+ x (/ eps 2.0)))) (sin (/ eps 2.0)))
(- (cos (+ x eps)) (cos x)))