Optimal throwing angle

Percentage Accurate: 68.6% → 99.6%
Time: 7.9s
Alternatives: 6
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \end{array} \]
(FPCore (v H)
 :precision binary64
 (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H))))))
double code(double v, double H) {
	return atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
}
real(8) function code(v, h)
    real(8), intent (in) :: v
    real(8), intent (in) :: h
    code = atan((v / sqrt(((v * v) - ((2.0d0 * 9.8d0) * h)))))
end function
public static double code(double v, double H) {
	return Math.atan((v / Math.sqrt(((v * v) - ((2.0 * 9.8) * H)))));
}
def code(v, H):
	return math.atan((v / math.sqrt(((v * v) - ((2.0 * 9.8) * H)))))
function code(v, H)
	return atan(Float64(v / sqrt(Float64(Float64(v * v) - Float64(Float64(2.0 * 9.8) * H)))))
end
function tmp = code(v, H)
	tmp = atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
end
code[v_, H_] := N[ArcTan[N[(v / N[Sqrt[N[(N[(v * v), $MachinePrecision] - N[(N[(2.0 * 9.8), $MachinePrecision] * H), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right)
\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 6 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: 68.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \end{array} \]
(FPCore (v H)
 :precision binary64
 (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H))))))
double code(double v, double H) {
	return atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
}
real(8) function code(v, h)
    real(8), intent (in) :: v
    real(8), intent (in) :: h
    code = atan((v / sqrt(((v * v) - ((2.0d0 * 9.8d0) * h)))))
end function
public static double code(double v, double H) {
	return Math.atan((v / Math.sqrt(((v * v) - ((2.0 * 9.8) * H)))));
}
def code(v, H):
	return math.atan((v / math.sqrt(((v * v) - ((2.0 * 9.8) * H)))))
function code(v, H)
	return atan(Float64(v / sqrt(Float64(Float64(v * v) - Float64(Float64(2.0 * 9.8) * H)))))
end
function tmp = code(v, H)
	tmp = atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
end
code[v_, H_] := N[ArcTan[N[(v / N[Sqrt[N[(N[(v * v), $MachinePrecision] - N[(N[(2.0 * 9.8), $MachinePrecision] * H), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right)
\end{array}

Alternative 1: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -5 \cdot 10^{+154}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 2 \cdot 10^{+130}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, -19.6 \cdot H\right)}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
(FPCore (v H)
 :precision binary64
 (if (<= v -5e+154)
   (atan -1.0)
   (if (<= v 2e+130) (atan (/ v (sqrt (fma v v (* -19.6 H))))) (atan 1.0))))
double code(double v, double H) {
	double tmp;
	if (v <= -5e+154) {
		tmp = atan(-1.0);
	} else if (v <= 2e+130) {
		tmp = atan((v / sqrt(fma(v, v, (-19.6 * H)))));
	} else {
		tmp = atan(1.0);
	}
	return tmp;
}
function code(v, H)
	tmp = 0.0
	if (v <= -5e+154)
		tmp = atan(-1.0);
	elseif (v <= 2e+130)
		tmp = atan(Float64(v / sqrt(fma(v, v, Float64(-19.6 * H)))));
	else
		tmp = atan(1.0);
	end
	return tmp
end
code[v_, H_] := If[LessEqual[v, -5e+154], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 2e+130], N[ArcTan[N[(v / N[Sqrt[N[(v * v + N[(-19.6 * H), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[ArcTan[1.0], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;v \leq -5 \cdot 10^{+154}:\\
\;\;\;\;\tan^{-1} -1\\

\mathbf{elif}\;v \leq 2 \cdot 10^{+130}:\\
\;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, -19.6 \cdot H\right)}}\right)\\

\mathbf{else}:\\
\;\;\;\;\tan^{-1} 1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if v < -5.00000000000000004e154

    1. Initial program 3.1%

      \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in v around -inf

      \[\leadsto \tan^{-1} \color{blue}{-1} \]
    4. Step-by-step derivation
      1. Applied rewrites100.0%

        \[\leadsto \tan^{-1} \color{blue}{-1} \]

      if -5.00000000000000004e154 < v < 2.0000000000000001e130

      1. Initial program 99.8%

        \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{v \cdot v - \left(2 \cdot \frac{49}{5}\right) \cdot H}}}\right) \]
        2. sub-negN/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{v \cdot v + \left(\mathsf{neg}\left(\left(2 \cdot \frac{49}{5}\right) \cdot H\right)\right)}}}\right) \]
        3. lift-*.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{v \cdot v} + \left(\mathsf{neg}\left(\left(2 \cdot \frac{49}{5}\right) \cdot H\right)\right)}}\right) \]
        4. lower-fma.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{\mathsf{fma}\left(v, v, \mathsf{neg}\left(\left(2 \cdot \frac{49}{5}\right) \cdot H\right)\right)}}}\right) \]
        5. lift-*.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \mathsf{neg}\left(\color{blue}{\left(2 \cdot \frac{49}{5}\right) \cdot H}\right)\right)}}\right) \]
        6. distribute-lft-neg-inN/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \color{blue}{\left(\mathsf{neg}\left(2 \cdot \frac{49}{5}\right)\right) \cdot H}\right)}}\right) \]
        7. lower-*.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \color{blue}{\left(\mathsf{neg}\left(2 \cdot \frac{49}{5}\right)\right) \cdot H}\right)}}\right) \]
        8. lift-*.f64N/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \left(\mathsf{neg}\left(\color{blue}{2 \cdot \frac{49}{5}}\right)\right) \cdot H\right)}}\right) \]
        9. metadata-evalN/A

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \left(\mathsf{neg}\left(\color{blue}{\frac{98}{5}}\right)\right) \cdot H\right)}}\right) \]
        10. metadata-eval99.8

          \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \color{blue}{-19.6} \cdot H\right)}}\right) \]
      4. Applied rewrites99.8%

        \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{\mathsf{fma}\left(v, v, -19.6 \cdot H\right)}}}\right) \]

      if 2.0000000000000001e130 < v

      1. Initial program 15.0%

        \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
      2. Add Preprocessing
      3. Taylor expanded in v around inf

        \[\leadsto \tan^{-1} \color{blue}{1} \]
      4. Step-by-step derivation
        1. Applied rewrites100.0%

          \[\leadsto \tan^{-1} \color{blue}{1} \]
      5. Recombined 3 regimes into one program.
      6. Add Preprocessing

      Alternative 2: 88.0% accurate, 1.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 12.2:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\frac{H}{-0.05102040816326531}}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\ \end{array} \end{array} \]
      (FPCore (v H)
       :precision binary64
       (if (<= v -6e-31)
         (atan -1.0)
         (if (<= v 12.2)
           (atan (/ v (sqrt (/ H -0.05102040816326531))))
           (atan (fma 9.8 (/ H (* v v)) 1.0)))))
      double code(double v, double H) {
      	double tmp;
      	if (v <= -6e-31) {
      		tmp = atan(-1.0);
      	} else if (v <= 12.2) {
      		tmp = atan((v / sqrt((H / -0.05102040816326531))));
      	} else {
      		tmp = atan(fma(9.8, (H / (v * v)), 1.0));
      	}
      	return tmp;
      }
      
      function code(v, H)
      	tmp = 0.0
      	if (v <= -6e-31)
      		tmp = atan(-1.0);
      	elseif (v <= 12.2)
      		tmp = atan(Float64(v / sqrt(Float64(H / -0.05102040816326531))));
      	else
      		tmp = atan(fma(9.8, Float64(H / Float64(v * v)), 1.0));
      	end
      	return tmp
      end
      
      code[v_, H_] := If[LessEqual[v, -6e-31], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 12.2], N[ArcTan[N[(v / N[Sqrt[N[(H / -0.05102040816326531), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(9.8 * N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\
      \;\;\;\;\tan^{-1} -1\\
      
      \mathbf{elif}\;v \leq 12.2:\\
      \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\frac{H}{-0.05102040816326531}}}\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if v < -5.99999999999999962e-31

        1. Initial program 56.5%

          \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in v around -inf

          \[\leadsto \tan^{-1} \color{blue}{-1} \]
        4. Step-by-step derivation
          1. Applied rewrites87.7%

            \[\leadsto \tan^{-1} \color{blue}{-1} \]

          if -5.99999999999999962e-31 < v < 12.199999999999999

          1. Initial program 99.6%

            \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in v around 0

            \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{\frac{-98}{5} \cdot H}}}\right) \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot \frac{-98}{5}}}}\right) \]
            2. lower-*.f6487.6

              \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot -19.6}}}\right) \]
          5. Applied rewrites87.6%

            \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot -19.6}}}\right) \]
          6. Step-by-step derivation
            1. Applied rewrites49.7%

              \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\frac{-384.16 \cdot \left(H \cdot H\right)}{\color{blue}{0 + 19.6 \cdot H}}}}\right) \]
            2. Applied rewrites87.7%

              \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\frac{-1}{\color{blue}{\frac{0.05102040816326531}{H}}}}}\right) \]
            3. Step-by-step derivation
              1. Applied rewrites87.7%

                \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\frac{H}{\color{blue}{-0.05102040816326531}}}}\right) \]

              if 12.199999999999999 < v

              1. Initial program 43.7%

                \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
              2. Add Preprocessing
              3. Taylor expanded in v around inf

                \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
              4. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \tan^{-1} \color{blue}{\left(\frac{49}{5} \cdot \frac{H}{{v}^{2}} + 1\right)} \]
                2. lower-fma.f64N/A

                  \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{{v}^{2}}, 1\right)\right)} \]
                3. lower-/.f64N/A

                  \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \color{blue}{\frac{H}{{v}^{2}}}, 1\right)\right) \]
                4. unpow2N/A

                  \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                5. lower-*.f6496.0

                  \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
              5. Applied rewrites96.0%

                \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)} \]
            4. Recombined 3 regimes into one program.
            5. Add Preprocessing

            Alternative 3: 87.9% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 12.2:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{-19.6 \cdot H}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\ \end{array} \end{array} \]
            (FPCore (v H)
             :precision binary64
             (if (<= v -6e-31)
               (atan -1.0)
               (if (<= v 12.2)
                 (atan (/ v (sqrt (* -19.6 H))))
                 (atan (fma 9.8 (/ H (* v v)) 1.0)))))
            double code(double v, double H) {
            	double tmp;
            	if (v <= -6e-31) {
            		tmp = atan(-1.0);
            	} else if (v <= 12.2) {
            		tmp = atan((v / sqrt((-19.6 * H))));
            	} else {
            		tmp = atan(fma(9.8, (H / (v * v)), 1.0));
            	}
            	return tmp;
            }
            
            function code(v, H)
            	tmp = 0.0
            	if (v <= -6e-31)
            		tmp = atan(-1.0);
            	elseif (v <= 12.2)
            		tmp = atan(Float64(v / sqrt(Float64(-19.6 * H))));
            	else
            		tmp = atan(fma(9.8, Float64(H / Float64(v * v)), 1.0));
            	end
            	return tmp
            end
            
            code[v_, H_] := If[LessEqual[v, -6e-31], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 12.2], N[ArcTan[N[(v / N[Sqrt[N[(-19.6 * H), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(9.8 * N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\
            \;\;\;\;\tan^{-1} -1\\
            
            \mathbf{elif}\;v \leq 12.2:\\
            \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{-19.6 \cdot H}}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if v < -5.99999999999999962e-31

              1. Initial program 56.5%

                \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
              2. Add Preprocessing
              3. Taylor expanded in v around -inf

                \[\leadsto \tan^{-1} \color{blue}{-1} \]
              4. Step-by-step derivation
                1. Applied rewrites87.7%

                  \[\leadsto \tan^{-1} \color{blue}{-1} \]

                if -5.99999999999999962e-31 < v < 12.199999999999999

                1. Initial program 99.6%

                  \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in v around 0

                  \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{\frac{-98}{5} \cdot H}}}\right) \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot \frac{-98}{5}}}}\right) \]
                  2. lower-*.f6487.6

                    \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot -19.6}}}\right) \]
                5. Applied rewrites87.6%

                  \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{H \cdot -19.6}}}\right) \]

                if 12.199999999999999 < v

                1. Initial program 43.7%

                  \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in v around inf

                  \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \tan^{-1} \color{blue}{\left(\frac{49}{5} \cdot \frac{H}{{v}^{2}} + 1\right)} \]
                  2. lower-fma.f64N/A

                    \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{{v}^{2}}, 1\right)\right)} \]
                  3. lower-/.f64N/A

                    \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \color{blue}{\frac{H}{{v}^{2}}}, 1\right)\right) \]
                  4. unpow2N/A

                    \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                  5. lower-*.f6496.0

                    \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                5. Applied rewrites96.0%

                  \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)} \]
              5. Recombined 3 regimes into one program.
              6. Final simplification90.1%

                \[\leadsto \begin{array}{l} \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 12.2:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{-19.6 \cdot H}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\ \end{array} \]
              7. Add Preprocessing

              Alternative 4: 88.0% accurate, 1.0× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 12.2:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\ \end{array} \end{array} \]
              (FPCore (v H)
               :precision binary64
               (if (<= v -6e-31)
                 (atan -1.0)
                 (if (<= v 12.2)
                   (atan (* (sqrt (/ -0.05102040816326531 H)) v))
                   (atan (fma 9.8 (/ H (* v v)) 1.0)))))
              double code(double v, double H) {
              	double tmp;
              	if (v <= -6e-31) {
              		tmp = atan(-1.0);
              	} else if (v <= 12.2) {
              		tmp = atan((sqrt((-0.05102040816326531 / H)) * v));
              	} else {
              		tmp = atan(fma(9.8, (H / (v * v)), 1.0));
              	}
              	return tmp;
              }
              
              function code(v, H)
              	tmp = 0.0
              	if (v <= -6e-31)
              		tmp = atan(-1.0);
              	elseif (v <= 12.2)
              		tmp = atan(Float64(sqrt(Float64(-0.05102040816326531 / H)) * v));
              	else
              		tmp = atan(fma(9.8, Float64(H / Float64(v * v)), 1.0));
              	end
              	return tmp
              end
              
              code[v_, H_] := If[LessEqual[v, -6e-31], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 12.2], N[ArcTan[N[(N[Sqrt[N[(-0.05102040816326531 / H), $MachinePrecision]], $MachinePrecision] * v), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(9.8 * N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;v \leq -6 \cdot 10^{-31}:\\
              \;\;\;\;\tan^{-1} -1\\
              
              \mathbf{elif}\;v \leq 12.2:\\
              \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if v < -5.99999999999999962e-31

                1. Initial program 56.5%

                  \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in v around -inf

                  \[\leadsto \tan^{-1} \color{blue}{-1} \]
                4. Step-by-step derivation
                  1. Applied rewrites87.7%

                    \[\leadsto \tan^{-1} \color{blue}{-1} \]

                  if -5.99999999999999962e-31 < v < 12.199999999999999

                  1. Initial program 99.6%

                    \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                  2. Add Preprocessing
                  3. Taylor expanded in v around 0

                    \[\leadsto \color{blue}{\tan^{-1} \left(v \cdot \sqrt{\frac{1}{{v}^{2} - \frac{98}{5} \cdot H}}\right)} \]
                  4. Step-by-step derivation
                    1. cancel-sign-sub-invN/A

                      \[\leadsto \tan^{-1} \left(v \cdot \sqrt{\frac{1}{\color{blue}{{v}^{2} + \left(\mathsf{neg}\left(\frac{98}{5}\right)\right) \cdot H}}}\right) \]
                    2. metadata-evalN/A

                      \[\leadsto \tan^{-1} \left(v \cdot \sqrt{\frac{1}{{v}^{2} + \color{blue}{\frac{-98}{5}} \cdot H}}\right) \]
                    3. +-commutativeN/A

                      \[\leadsto \tan^{-1} \left(v \cdot \sqrt{\frac{1}{\color{blue}{\frac{-98}{5} \cdot H + {v}^{2}}}}\right) \]
                    4. lower-atan.f64N/A

                      \[\leadsto \color{blue}{\tan^{-1} \left(v \cdot \sqrt{\frac{1}{\frac{-98}{5} \cdot H + {v}^{2}}}\right)} \]
                    5. *-commutativeN/A

                      \[\leadsto \tan^{-1} \color{blue}{\left(\sqrt{\frac{1}{\frac{-98}{5} \cdot H + {v}^{2}}} \cdot v\right)} \]
                    6. lower-*.f64N/A

                      \[\leadsto \tan^{-1} \color{blue}{\left(\sqrt{\frac{1}{\frac{-98}{5} \cdot H + {v}^{2}}} \cdot v\right)} \]
                    7. lower-sqrt.f64N/A

                      \[\leadsto \tan^{-1} \left(\color{blue}{\sqrt{\frac{1}{\frac{-98}{5} \cdot H + {v}^{2}}}} \cdot v\right) \]
                    8. lower-/.f64N/A

                      \[\leadsto \tan^{-1} \left(\sqrt{\color{blue}{\frac{1}{\frac{-98}{5} \cdot H + {v}^{2}}}} \cdot v\right) \]
                    9. +-commutativeN/A

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\color{blue}{{v}^{2} + \frac{-98}{5} \cdot H}}} \cdot v\right) \]
                    10. unpow2N/A

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\color{blue}{v \cdot v} + \frac{-98}{5} \cdot H}} \cdot v\right) \]
                    11. lower-fma.f64N/A

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\color{blue}{\mathsf{fma}\left(v, v, \frac{-98}{5} \cdot H\right)}}} \cdot v\right) \]
                    12. *-commutativeN/A

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(v, v, \color{blue}{H \cdot \frac{-98}{5}}\right)}} \cdot v\right) \]
                    13. lower-*.f6499.5

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(v, v, \color{blue}{H \cdot -19.6}\right)}} \cdot v\right) \]
                  5. Applied rewrites99.5%

                    \[\leadsto \color{blue}{\tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(v, v, H \cdot -19.6\right)}} \cdot v\right)} \]
                  6. Taylor expanded in v around 0

                    \[\leadsto \tan^{-1} \left(\sqrt{\frac{\frac{-5}{98}}{H}} \cdot v\right) \]
                  7. Step-by-step derivation
                    1. Applied rewrites87.6%

                      \[\leadsto \tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right) \]

                    if 12.199999999999999 < v

                    1. Initial program 43.7%

                      \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                    2. Add Preprocessing
                    3. Taylor expanded in v around inf

                      \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
                    4. Step-by-step derivation
                      1. +-commutativeN/A

                        \[\leadsto \tan^{-1} \color{blue}{\left(\frac{49}{5} \cdot \frac{H}{{v}^{2}} + 1\right)} \]
                      2. lower-fma.f64N/A

                        \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{{v}^{2}}, 1\right)\right)} \]
                      3. lower-/.f64N/A

                        \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \color{blue}{\frac{H}{{v}^{2}}}, 1\right)\right) \]
                      4. unpow2N/A

                        \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(\frac{49}{5}, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                      5. lower-*.f6496.0

                        \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                    5. Applied rewrites96.0%

                      \[\leadsto \tan^{-1} \color{blue}{\left(\mathsf{fma}\left(9.8, \frac{H}{v \cdot v}, 1\right)\right)} \]
                  8. Recombined 3 regimes into one program.
                  9. Add Preprocessing

                  Alternative 5: 67.2% accurate, 1.3× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
                  (FPCore (v H) :precision binary64 (if (<= v -5e-310) (atan -1.0) (atan 1.0)))
                  double code(double v, double H) {
                  	double tmp;
                  	if (v <= -5e-310) {
                  		tmp = atan(-1.0);
                  	} else {
                  		tmp = atan(1.0);
                  	}
                  	return tmp;
                  }
                  
                  real(8) function code(v, h)
                      real(8), intent (in) :: v
                      real(8), intent (in) :: h
                      real(8) :: tmp
                      if (v <= (-5d-310)) then
                          tmp = atan((-1.0d0))
                      else
                          tmp = atan(1.0d0)
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double v, double H) {
                  	double tmp;
                  	if (v <= -5e-310) {
                  		tmp = Math.atan(-1.0);
                  	} else {
                  		tmp = Math.atan(1.0);
                  	}
                  	return tmp;
                  }
                  
                  def code(v, H):
                  	tmp = 0
                  	if v <= -5e-310:
                  		tmp = math.atan(-1.0)
                  	else:
                  		tmp = math.atan(1.0)
                  	return tmp
                  
                  function code(v, H)
                  	tmp = 0.0
                  	if (v <= -5e-310)
                  		tmp = atan(-1.0);
                  	else
                  		tmp = atan(1.0);
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(v, H)
                  	tmp = 0.0;
                  	if (v <= -5e-310)
                  		tmp = atan(-1.0);
                  	else
                  		tmp = atan(1.0);
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[v_, H_] := If[LessEqual[v, -5e-310], N[ArcTan[-1.0], $MachinePrecision], N[ArcTan[1.0], $MachinePrecision]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  \mathbf{if}\;v \leq -5 \cdot 10^{-310}:\\
                  \;\;\;\;\tan^{-1} -1\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\tan^{-1} 1\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if v < -4.999999999999985e-310

                    1. Initial program 68.1%

                      \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                    2. Add Preprocessing
                    3. Taylor expanded in v around -inf

                      \[\leadsto \tan^{-1} \color{blue}{-1} \]
                    4. Step-by-step derivation
                      1. Applied rewrites69.2%

                        \[\leadsto \tan^{-1} \color{blue}{-1} \]

                      if -4.999999999999985e-310 < v

                      1. Initial program 66.5%

                        \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                      2. Add Preprocessing
                      3. Taylor expanded in v around inf

                        \[\leadsto \tan^{-1} \color{blue}{1} \]
                      4. Step-by-step derivation
                        1. Applied rewrites63.8%

                          \[\leadsto \tan^{-1} \color{blue}{1} \]
                      5. Recombined 2 regimes into one program.
                      6. Add Preprocessing

                      Alternative 6: 33.8% accurate, 1.4× speedup?

                      \[\begin{array}{l} \\ \tan^{-1} -1 \end{array} \]
                      (FPCore (v H) :precision binary64 (atan -1.0))
                      double code(double v, double H) {
                      	return atan(-1.0);
                      }
                      
                      real(8) function code(v, h)
                          real(8), intent (in) :: v
                          real(8), intent (in) :: h
                          code = atan((-1.0d0))
                      end function
                      
                      public static double code(double v, double H) {
                      	return Math.atan(-1.0);
                      }
                      
                      def code(v, H):
                      	return math.atan(-1.0)
                      
                      function code(v, H)
                      	return atan(-1.0)
                      end
                      
                      function tmp = code(v, H)
                      	tmp = atan(-1.0);
                      end
                      
                      code[v_, H_] := N[ArcTan[-1.0], $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \tan^{-1} -1
                      \end{array}
                      
                      Derivation
                      1. Initial program 67.3%

                        \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                      2. Add Preprocessing
                      3. Taylor expanded in v around -inf

                        \[\leadsto \tan^{-1} \color{blue}{-1} \]
                      4. Step-by-step derivation
                        1. Applied rewrites36.3%

                          \[\leadsto \tan^{-1} \color{blue}{-1} \]
                        2. Add Preprocessing

                        Reproduce

                        ?
                        herbie shell --seed 2024268 
                        (FPCore (v H)
                          :name "Optimal throwing angle"
                          :precision binary64
                          (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H))))))