
(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 9 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 (* 0.5 (fma 2.0 x eps))) (* -2.0 (sin (* 0.5 eps)))))
double code(double x, double eps) {
return sin((0.5 * fma(2.0, x, eps))) * (-2.0 * sin((0.5 * eps)));
}
function code(x, eps) return Float64(sin(Float64(0.5 * fma(2.0, x, eps))) * Float64(-2.0 * sin(Float64(0.5 * eps)))) end
code[x_, eps_] := N[(N[Sin[N[(0.5 * N[(2.0 * x + eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(-2.0 * N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(-2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)
\end{array}
Initial program 53.3%
diff-cos79.3%
div-inv79.3%
associate--l+79.3%
metadata-eval79.3%
div-inv79.3%
+-commutative79.3%
associate-+l+79.3%
metadata-eval79.3%
Applied egg-rr79.3%
associate-*r*79.3%
*-commutative79.3%
*-commutative79.3%
+-commutative79.3%
count-279.3%
fma-define79.3%
*-commutative79.3%
associate-+r-79.3%
+-commutative79.3%
associate--l+99.7%
+-inverses99.7%
distribute-lft-in99.7%
metadata-eval99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (x eps) :precision binary64 (* -2.0 (* (sin (* 0.5 eps)) (sin (+ x (* 0.5 eps))))))
double code(double x, double eps) {
return -2.0 * (sin((0.5 * eps)) * sin((x + (0.5 * eps))));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = (-2.0d0) * (sin((0.5d0 * eps)) * sin((x + (0.5d0 * eps))))
end function
public static double code(double x, double eps) {
return -2.0 * (Math.sin((0.5 * eps)) * Math.sin((x + (0.5 * eps))));
}
def code(x, eps): return -2.0 * (math.sin((0.5 * eps)) * math.sin((x + (0.5 * eps))))
function code(x, eps) return Float64(-2.0 * Float64(sin(Float64(0.5 * eps)) * sin(Float64(x + Float64(0.5 * eps))))) end
function tmp = code(x, eps) tmp = -2.0 * (sin((0.5 * eps)) * sin((x + (0.5 * eps)))); end
code[x_, eps_] := N[(-2.0 * N[(N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision] * N[Sin[N[(x + N[(0.5 * eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(x + 0.5 \cdot \varepsilon\right)\right)
\end{array}
Initial program 53.3%
diff-cos79.3%
div-inv79.3%
associate--l+79.3%
metadata-eval79.3%
div-inv79.3%
+-commutative79.3%
associate-+l+79.3%
metadata-eval79.3%
Applied egg-rr79.3%
associate-*r*79.3%
*-commutative79.3%
*-commutative79.3%
+-commutative79.3%
count-279.3%
fma-define79.3%
*-commutative79.3%
associate-+r-79.3%
+-commutative79.3%
associate--l+99.7%
+-inverses99.7%
distribute-lft-in99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in x around inf 99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (x eps) :precision binary64 (* (sin (+ x (* 0.5 eps))) (- eps)))
double code(double x, double eps) {
return sin((x + (0.5 * eps))) * -eps;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = sin((x + (0.5d0 * eps))) * -eps
end function
public static double code(double x, double eps) {
return Math.sin((x + (0.5 * eps))) * -eps;
}
def code(x, eps): return math.sin((x + (0.5 * eps))) * -eps
function code(x, eps) return Float64(sin(Float64(x + Float64(0.5 * eps))) * Float64(-eps)) end
function tmp = code(x, eps) tmp = sin((x + (0.5 * eps))) * -eps; end
code[x_, eps_] := N[(N[Sin[N[(x + N[(0.5 * eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * (-eps)), $MachinePrecision]
\begin{array}{l}
\\
\sin \left(x + 0.5 \cdot \varepsilon\right) \cdot \left(-\varepsilon\right)
\end{array}
Initial program 53.3%
diff-cos79.3%
div-inv79.3%
associate--l+79.3%
metadata-eval79.3%
div-inv79.3%
+-commutative79.3%
associate-+l+79.3%
metadata-eval79.3%
Applied egg-rr79.3%
associate-*r*79.3%
*-commutative79.3%
*-commutative79.3%
+-commutative79.3%
count-279.3%
fma-define79.3%
*-commutative79.3%
associate-+r-79.3%
+-commutative79.3%
associate--l+99.7%
+-inverses99.7%
distribute-lft-in99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in eps around 0 99.6%
mul-1-neg99.6%
Simplified99.6%
Taylor expanded in x around inf 99.6%
distribute-lft-in99.6%
associate-*r*99.6%
metadata-eval99.6%
*-lft-identity99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (x eps) :precision binary64 (* eps (- (* eps -0.5) (sin x))))
double code(double x, double eps) {
return eps * ((eps * -0.5) - sin(x));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * ((eps * (-0.5d0)) - sin(x))
end function
public static double code(double x, double eps) {
return eps * ((eps * -0.5) - Math.sin(x));
}
def code(x, eps): return eps * ((eps * -0.5) - math.sin(x))
function code(x, eps) return Float64(eps * Float64(Float64(eps * -0.5) - sin(x))) end
function tmp = code(x, eps) tmp = eps * ((eps * -0.5) - sin(x)); end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 - \sin x\right)
\end{array}
Initial program 53.3%
Taylor expanded in eps around 0 99.6%
associate-*r*99.6%
Simplified99.6%
Taylor expanded in x around 0 99.2%
*-commutative99.2%
Simplified99.2%
(FPCore (x eps) :precision binary64 (* eps (+ (* eps -0.5) (* x (+ (* x (+ (* x 0.16666666666666666) (* eps 0.25))) -1.0)))))
double code(double x, double eps) {
return eps * ((eps * -0.5) + (x * ((x * ((x * 0.16666666666666666) + (eps * 0.25))) + -1.0)));
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * ((eps * (-0.5d0)) + (x * ((x * ((x * 0.16666666666666666d0) + (eps * 0.25d0))) + (-1.0d0))))
end function
public static double code(double x, double eps) {
return eps * ((eps * -0.5) + (x * ((x * ((x * 0.16666666666666666) + (eps * 0.25))) + -1.0)));
}
def code(x, eps): return eps * ((eps * -0.5) + (x * ((x * ((x * 0.16666666666666666) + (eps * 0.25))) + -1.0)))
function code(x, eps) return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(Float64(x * Float64(Float64(x * 0.16666666666666666) + Float64(eps * 0.25))) + -1.0)))) end
function tmp = code(x, eps) tmp = eps * ((eps * -0.5) + (x * ((x * ((x * 0.16666666666666666) + (eps * 0.25))) + -1.0))); end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(N[(x * N[(N[(x * 0.16666666666666666), $MachinePrecision] + N[(eps * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(x \cdot \left(x \cdot 0.16666666666666666 + \varepsilon \cdot 0.25\right) + -1\right)\right)
\end{array}
Initial program 53.3%
Taylor expanded in eps around 0 99.6%
associate-*r*99.6%
Simplified99.6%
Taylor expanded in x around 0 98.6%
Final simplification98.6%
(FPCore (x eps) :precision binary64 (* eps (- (* eps (- (* 0.16666666666666666 (* x eps)) 0.5)) x)))
double code(double x, double eps) {
return eps * ((eps * ((0.16666666666666666 * (x * eps)) - 0.5)) - x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * ((eps * ((0.16666666666666666d0 * (x * eps)) - 0.5d0)) - x)
end function
public static double code(double x, double eps) {
return eps * ((eps * ((0.16666666666666666 * (x * eps)) - 0.5)) - x);
}
def code(x, eps): return eps * ((eps * ((0.16666666666666666 * (x * eps)) - 0.5)) - x)
function code(x, eps) return Float64(eps * Float64(Float64(eps * Float64(Float64(0.16666666666666666 * Float64(x * eps)) - 0.5)) - x)) end
function tmp = code(x, eps) tmp = eps * ((eps * ((0.16666666666666666 * (x * eps)) - 0.5)) - x); end
code[x_, eps_] := N[(eps * N[(N[(eps * N[(N[(0.16666666666666666 * N[(x * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\varepsilon \cdot \left(0.16666666666666666 \cdot \left(x \cdot \varepsilon\right) - 0.5\right) - x\right)
\end{array}
Initial program 53.3%
Taylor expanded in x around 0 52.8%
associate--l+52.9%
associate-*r*52.9%
mul-1-neg52.9%
Simplified52.9%
Taylor expanded in eps around 0 98.1%
Final simplification98.1%
(FPCore (x eps) :precision binary64 (* eps (- (* eps -0.5) x)))
double code(double x, double eps) {
return eps * ((eps * -0.5) - x);
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = eps * ((eps * (-0.5d0)) - x)
end function
public static double code(double x, double eps) {
return eps * ((eps * -0.5) - x);
}
def code(x, eps): return eps * ((eps * -0.5) - x)
function code(x, eps) return Float64(eps * Float64(Float64(eps * -0.5) - x)) end
function tmp = code(x, eps) tmp = eps * ((eps * -0.5) - x); end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 - x\right)
\end{array}
Initial program 53.3%
Taylor expanded in x around 0 52.8%
associate--l+52.9%
associate-*r*52.9%
mul-1-neg52.9%
Simplified52.9%
Taylor expanded in eps around 0 98.1%
+-commutative98.1%
mul-1-neg98.1%
unsub-neg98.1%
*-commutative98.1%
Simplified98.1%
(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 53.3%
Taylor expanded in eps around 0 81.9%
associate-*r*81.9%
mul-1-neg81.9%
Simplified81.9%
Taylor expanded in x around 0 81.0%
associate-*r*81.0%
mul-1-neg81.0%
Simplified81.0%
Final simplification81.0%
(FPCore (x eps) :precision binary64 0.0)
double code(double x, double eps) {
return 0.0;
}
real(8) function code(x, eps)
real(8), intent (in) :: x
real(8), intent (in) :: eps
code = 0.0d0
end function
public static double code(double x, double eps) {
return 0.0;
}
def code(x, eps): return 0.0
function code(x, eps) return 0.0 end
function tmp = code(x, eps) tmp = 0.0; end
code[x_, eps_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 53.3%
Taylor expanded in x around 0 52.3%
Taylor expanded in eps around 0 52.3%
metadata-eval52.3%
Applied egg-rr52.3%
(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 2024141
(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 (* -2 (sin (+ x (/ eps 2))) (sin (/ eps 2))))
(- (cos (+ x eps)) (cos x)))