Example 2 from Robby

Percentage Accurate: 99.8% → 99.8%
Time: 19.6s
Alternatives: 7
Speedup: N/A×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_1 := \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\\ \left|\left(ew \cdot \cos t\right) \cdot \cos t\_1 - \left(eh \cdot \sin t\right) \cdot \sin t\_1\right| \end{array} \end{array} \]
(FPCore (eh ew t)
 :precision binary64
 (let* ((t_1 (atan (/ (* (- eh) (tan t)) ew))))
   (fabs (- (* (* ew (cos t)) (cos t_1)) (* (* eh (sin t)) (sin t_1))))))
double code(double eh, double ew, double t) {
	double t_1 = atan(((-eh * tan(t)) / ew));
	return fabs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))));
}
real(8) function code(eh, ew, t)
    real(8), intent (in) :: eh
    real(8), intent (in) :: ew
    real(8), intent (in) :: t
    real(8) :: t_1
    t_1 = atan(((-eh * tan(t)) / ew))
    code = abs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))))
end function
public static double code(double eh, double ew, double t) {
	double t_1 = Math.atan(((-eh * Math.tan(t)) / ew));
	return Math.abs((((ew * Math.cos(t)) * Math.cos(t_1)) - ((eh * Math.sin(t)) * Math.sin(t_1))));
}
def code(eh, ew, t):
	t_1 = math.atan(((-eh * math.tan(t)) / ew))
	return math.fabs((((ew * math.cos(t)) * math.cos(t_1)) - ((eh * math.sin(t)) * math.sin(t_1))))
function code(eh, ew, t)
	t_1 = atan(Float64(Float64(Float64(-eh) * tan(t)) / ew))
	return abs(Float64(Float64(Float64(ew * cos(t)) * cos(t_1)) - Float64(Float64(eh * sin(t)) * sin(t_1))))
end
function tmp = code(eh, ew, t)
	t_1 = atan(((-eh * tan(t)) / ew));
	tmp = abs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))));
end
code[eh_, ew_, t_] := Block[{t$95$1 = N[ArcTan[N[(N[((-eh) * N[Tan[t], $MachinePrecision]), $MachinePrecision] / ew), $MachinePrecision]], $MachinePrecision]}, N[Abs[N[(N[(N[(ew * N[Cos[t], $MachinePrecision]), $MachinePrecision] * N[Cos[t$95$1], $MachinePrecision]), $MachinePrecision] - N[(N[(eh * N[Sin[t], $MachinePrecision]), $MachinePrecision] * N[Sin[t$95$1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\\
\left|\left(ew \cdot \cos t\right) \cdot \cos t\_1 - \left(eh \cdot \sin t\right) \cdot \sin t\_1\right|
\end{array}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 7 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 99.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\\ \left|\left(ew \cdot \cos t\right) \cdot \cos t\_1 - \left(eh \cdot \sin t\right) \cdot \sin t\_1\right| \end{array} \end{array} \]
(FPCore (eh ew t)
 :precision binary64
 (let* ((t_1 (atan (/ (* (- eh) (tan t)) ew))))
   (fabs (- (* (* ew (cos t)) (cos t_1)) (* (* eh (sin t)) (sin t_1))))))
double code(double eh, double ew, double t) {
	double t_1 = atan(((-eh * tan(t)) / ew));
	return fabs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))));
}
real(8) function code(eh, ew, t)
    real(8), intent (in) :: eh
    real(8), intent (in) :: ew
    real(8), intent (in) :: t
    real(8) :: t_1
    t_1 = atan(((-eh * tan(t)) / ew))
    code = abs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))))
end function
public static double code(double eh, double ew, double t) {
	double t_1 = Math.atan(((-eh * Math.tan(t)) / ew));
	return Math.abs((((ew * Math.cos(t)) * Math.cos(t_1)) - ((eh * Math.sin(t)) * Math.sin(t_1))));
}
def code(eh, ew, t):
	t_1 = math.atan(((-eh * math.tan(t)) / ew))
	return math.fabs((((ew * math.cos(t)) * math.cos(t_1)) - ((eh * math.sin(t)) * math.sin(t_1))))
function code(eh, ew, t)
	t_1 = atan(Float64(Float64(Float64(-eh) * tan(t)) / ew))
	return abs(Float64(Float64(Float64(ew * cos(t)) * cos(t_1)) - Float64(Float64(eh * sin(t)) * sin(t_1))))
end
function tmp = code(eh, ew, t)
	t_1 = atan(((-eh * tan(t)) / ew));
	tmp = abs((((ew * cos(t)) * cos(t_1)) - ((eh * sin(t)) * sin(t_1))));
end
code[eh_, ew_, t_] := Block[{t$95$1 = N[ArcTan[N[(N[((-eh) * N[Tan[t], $MachinePrecision]), $MachinePrecision] / ew), $MachinePrecision]], $MachinePrecision]}, N[Abs[N[(N[(N[(ew * N[Cos[t], $MachinePrecision]), $MachinePrecision] * N[Cos[t$95$1], $MachinePrecision]), $MachinePrecision] - N[(N[(eh * N[Sin[t], $MachinePrecision]), $MachinePrecision] * N[Sin[t$95$1], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\\
\left|\left(ew \cdot \cos t\right) \cdot \cos t\_1 - \left(eh \cdot \sin t\right) \cdot \sin t\_1\right|
\end{array}
\end{array}

Alternative 1: 99.8% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(-eh\right) \cdot \frac{\tan t}{ew}\\ \left|\mathsf{fma}\left(\frac{\cos t}{\sqrt{1 + {t\_1}^{2}}}, ew, \left(-eh \cdot \sin t\right) \cdot \sin \tan^{-1} t\_1\right)\right| \end{array} \end{array} \]
(FPCore (eh ew t)
 :precision binary64
 (let* ((t_1 (* (- eh) (/ (tan t) ew))))
   (fabs
    (fma
     (/ (cos t) (sqrt (+ 1.0 (pow t_1 2.0))))
     ew
     (* (- (* eh (sin t))) (sin (atan t_1)))))))
double code(double eh, double ew, double t) {
	double t_1 = -eh * (tan(t) / ew);
	return fabs(fma((cos(t) / sqrt((1.0 + pow(t_1, 2.0)))), ew, (-(eh * sin(t)) * sin(atan(t_1)))));
}
function code(eh, ew, t)
	t_1 = Float64(Float64(-eh) * Float64(tan(t) / ew))
	return abs(fma(Float64(cos(t) / sqrt(Float64(1.0 + (t_1 ^ 2.0)))), ew, Float64(Float64(-Float64(eh * sin(t))) * sin(atan(t_1)))))
end
code[eh_, ew_, t_] := Block[{t$95$1 = N[((-eh) * N[(N[Tan[t], $MachinePrecision] / ew), $MachinePrecision]), $MachinePrecision]}, N[Abs[N[(N[(N[Cos[t], $MachinePrecision] / N[Sqrt[N[(1.0 + N[Power[t$95$1, 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * ew + N[((-N[(eh * N[Sin[t], $MachinePrecision]), $MachinePrecision]) * N[Sin[N[ArcTan[t$95$1], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(-eh\right) \cdot \frac{\tan t}{ew}\\
\left|\mathsf{fma}\left(\frac{\cos t}{\sqrt{1 + {t\_1}^{2}}}, ew, \left(-eh \cdot \sin t\right) \cdot \sin \tan^{-1} t\_1\right)\right|
\end{array}
\end{array}
Derivation
  1. Initial program 99.8%

    \[\left|\left(ew \cdot \cos t\right) \cdot \cos \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right) - \left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\right| \]
  2. Add Preprocessing
  3. Applied egg-rr99.8%

    \[\leadsto \left|\color{blue}{\mathsf{fma}\left(\frac{\cos t}{\sqrt{1 + {\left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}^{2}}}, ew, -\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)\right)}\right| \]
  4. Final simplification99.8%

    \[\leadsto \left|\mathsf{fma}\left(\frac{\cos t}{\sqrt{1 + {\left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}^{2}}}, ew, \left(-eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)\right)\right| \]
  5. Add Preprocessing

Alternative 2: 91.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left|ew \cdot \mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}{ew}, -\cos t\right)\right|\\ \mathbf{if}\;ew \leq -8.5 \cdot 10^{-191}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;ew \leq 3.8 \cdot 10^{-282}:\\ \;\;\;\;\left|\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{eh \cdot \tan t}{-ew}\right)\right|\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (eh ew t)
 :precision binary64
 (let* ((t_1
         (fabs
          (*
           ew
           (fma
            eh
            (/ (* (sin t) (sin (atan (* (- eh) (/ (tan t) ew))))) ew)
            (- (cos t)))))))
   (if (<= ew -8.5e-191)
     t_1
     (if (<= ew 3.8e-282)
       (fabs (* (* eh (sin t)) (sin (atan (/ (* eh (tan t)) (- ew))))))
       t_1))))
double code(double eh, double ew, double t) {
	double t_1 = fabs((ew * fma(eh, ((sin(t) * sin(atan((-eh * (tan(t) / ew))))) / ew), -cos(t))));
	double tmp;
	if (ew <= -8.5e-191) {
		tmp = t_1;
	} else if (ew <= 3.8e-282) {
		tmp = fabs(((eh * sin(t)) * sin(atan(((eh * tan(t)) / -ew)))));
	} else {
		tmp = t_1;
	}
	return tmp;
}
function code(eh, ew, t)
	t_1 = abs(Float64(ew * fma(eh, Float64(Float64(sin(t) * sin(atan(Float64(Float64(-eh) * Float64(tan(t) / ew))))) / ew), Float64(-cos(t)))))
	tmp = 0.0
	if (ew <= -8.5e-191)
		tmp = t_1;
	elseif (ew <= 3.8e-282)
		tmp = abs(Float64(Float64(eh * sin(t)) * sin(atan(Float64(Float64(eh * tan(t)) / Float64(-ew))))));
	else
		tmp = t_1;
	end
	return tmp
end
code[eh_, ew_, t_] := Block[{t$95$1 = N[Abs[N[(ew * N[(eh * N[(N[(N[Sin[t], $MachinePrecision] * N[Sin[N[ArcTan[N[((-eh) * N[(N[Tan[t], $MachinePrecision] / ew), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / ew), $MachinePrecision] + (-N[Cos[t], $MachinePrecision])), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[ew, -8.5e-191], t$95$1, If[LessEqual[ew, 3.8e-282], N[Abs[N[(N[(eh * N[Sin[t], $MachinePrecision]), $MachinePrecision] * N[Sin[N[ArcTan[N[(N[(eh * N[Tan[t], $MachinePrecision]), $MachinePrecision] / (-ew)), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], t$95$1]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left|ew \cdot \mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}{ew}, -\cos t\right)\right|\\
\mathbf{if}\;ew \leq -8.5 \cdot 10^{-191}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;ew \leq 3.8 \cdot 10^{-282}:\\
\;\;\;\;\left|\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{eh \cdot \tan t}{-ew}\right)\right|\\

\mathbf{else}:\\
\;\;\;\;t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if ew < -8.49999999999999954e-191 or 3.79999999999999992e-282 < ew

    1. Initial program 99.8%

      \[\left|\left(ew \cdot \cos t\right) \cdot \cos \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right) - \left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\right| \]
    2. Add Preprocessing
    3. Applied egg-rr99.8%

      \[\leadsto \left|\color{blue}{\mathsf{fma}\left(\frac{\cos t}{\sqrt{1 + {\left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}^{2}}}, ew, -\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)\right)}\right| \]
    4. Taylor expanded in ew around -inf

      \[\leadsto \left|\color{blue}{-1 \cdot \left(ew \cdot \left(-1 \cdot \cos t + \frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew}\right)\right)}\right| \]
    5. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \left|\color{blue}{\left(-1 \cdot ew\right) \cdot \left(-1 \cdot \cos t + \frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew}\right)}\right| \]
      2. lower-*.f64N/A

        \[\leadsto \left|\color{blue}{\left(-1 \cdot ew\right) \cdot \left(-1 \cdot \cos t + \frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew}\right)}\right| \]
      3. mul-1-negN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(ew\right)\right)} \cdot \left(-1 \cdot \cos t + \frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew}\right)\right| \]
      4. lower-neg.f64N/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(ew\right)\right)} \cdot \left(-1 \cdot \cos t + \frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew}\right)\right| \]
      5. +-commutativeN/A

        \[\leadsto \left|\left(\mathsf{neg}\left(ew\right)\right) \cdot \color{blue}{\left(\frac{eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}{ew} + -1 \cdot \cos t\right)}\right| \]
      6. associate-/l*N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(ew\right)\right) \cdot \left(\color{blue}{eh \cdot \frac{\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)}{ew}} + -1 \cdot \cos t\right)\right| \]
      7. lower-fma.f64N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(ew\right)\right) \cdot \color{blue}{\mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)}{ew}, -1 \cdot \cos t\right)}\right| \]
    6. Simplified93.1%

      \[\leadsto \left|\color{blue}{\left(-ew\right) \cdot \mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(-eh \cdot \frac{\tan t}{ew}\right)}{ew}, -\cos t\right)}\right| \]

    if -8.49999999999999954e-191 < ew < 3.79999999999999992e-282

    1. Initial program 99.8%

      \[\left|\left(ew \cdot \cos t\right) \cdot \cos \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right) - \left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{\left(-eh\right) \cdot \tan t}{ew}\right)\right| \]
    2. Add Preprocessing
    3. Taylor expanded in ew around 0

      \[\leadsto \left|\color{blue}{-1 \cdot \left(eh \cdot \left(\sin t \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)\right)}\right| \]
    4. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \left|-1 \cdot \color{blue}{\left(\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)\right)}\right| \]
      2. associate-*r*N/A

        \[\leadsto \left|\color{blue}{\left(-1 \cdot \left(eh \cdot \sin t\right)\right) \cdot \sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)}\right| \]
      3. *-commutativeN/A

        \[\leadsto \left|\color{blue}{\sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)}\right| \]
      4. lower-*.f64N/A

        \[\leadsto \left|\color{blue}{\sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)}\right| \]
      5. lower-sin.f64N/A

        \[\leadsto \left|\color{blue}{\sin \tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)} \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      6. lower-atan.f64N/A

        \[\leadsto \left|\sin \color{blue}{\tan^{-1} \left(-1 \cdot \frac{eh \cdot \tan t}{ew}\right)} \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      7. mul-1-negN/A

        \[\leadsto \left|\sin \tan^{-1} \color{blue}{\left(\mathsf{neg}\left(\frac{eh \cdot \tan t}{ew}\right)\right)} \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      8. distribute-neg-frac2N/A

        \[\leadsto \left|\sin \tan^{-1} \color{blue}{\left(\frac{eh \cdot \tan t}{\mathsf{neg}\left(ew\right)}\right)} \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      9. mul-1-negN/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\color{blue}{-1 \cdot ew}}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      10. lower-/.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \color{blue}{\left(\frac{eh \cdot \tan t}{-1 \cdot ew}\right)} \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      11. lower-*.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{\color{blue}{eh \cdot \tan t}}{-1 \cdot ew}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      12. lower-tan.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \color{blue}{\tan t}}{-1 \cdot ew}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      13. mul-1-negN/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\color{blue}{\mathsf{neg}\left(ew\right)}}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      14. lower-neg.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\color{blue}{\mathsf{neg}\left(ew\right)}}\right) \cdot \left(-1 \cdot \left(eh \cdot \sin t\right)\right)\right| \]
      15. mul-1-negN/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\mathsf{neg}\left(ew\right)}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(eh \cdot \sin t\right)\right)}\right| \]
      16. lower-neg.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\mathsf{neg}\left(ew\right)}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(eh \cdot \sin t\right)\right)}\right| \]
      17. lower-*.f64N/A

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{\mathsf{neg}\left(ew\right)}\right) \cdot \left(\mathsf{neg}\left(\color{blue}{eh \cdot \sin t}\right)\right)\right| \]
      18. lower-sin.f6480.4

        \[\leadsto \left|\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{-ew}\right) \cdot \left(-eh \cdot \color{blue}{\sin t}\right)\right| \]
    5. Simplified80.4%

      \[\leadsto \left|\color{blue}{\sin \tan^{-1} \left(\frac{eh \cdot \tan t}{-ew}\right) \cdot \left(-eh \cdot \sin t\right)}\right| \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;ew \leq -8.5 \cdot 10^{-191}:\\ \;\;\;\;\left|ew \cdot \mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}{ew}, -\cos t\right)\right|\\ \mathbf{elif}\;ew \leq 3.8 \cdot 10^{-282}:\\ \;\;\;\;\left|\left(eh \cdot \sin t\right) \cdot \sin \tan^{-1} \left(\frac{eh \cdot \tan t}{-ew}\right)\right|\\ \mathbf{else}:\\ \;\;\;\;\left|ew \cdot \mathsf{fma}\left(eh, \frac{\sin t \cdot \sin \tan^{-1} \left(\left(-eh\right) \cdot \frac{\tan t}{ew}\right)}{ew}, -\cos t\right)\right|\\ \end{array} \]
  5. Add Preprocessing

Reproduce

?
herbie shell --seed 2024218 
(FPCore (eh ew t)
  :name "Example 2 from Robby"
  :precision binary64
  (fabs (- (* (* ew (cos t)) (cos (atan (/ (* (- eh) (tan t)) ew)))) (* (* eh (sin t)) (sin (atan (/ (* (- eh) (tan t)) ew)))))))