Optimal throwing angle

Percentage Accurate: 66.7% → 98.5%
Time: 3.6s
Alternatives: 6
Speedup: 1.3×

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)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(v, h)
use fmin_fmax_functions
    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: 66.7% 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)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(v, h)
use fmin_fmax_functions
    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: 98.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -5 \cdot 10^{+154}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 4.9 \cdot 10^{+33}:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(\frac{H}{v \cdot v}, 9.8, 1\right)\right)\\ \end{array} \end{array} \]
(FPCore (v H)
 :precision binary64
 (if (<= v -5e+154)
   (atan -1.0)
   (if (<= v 4.9e+33)
     (atan (* (sqrt (/ 1.0 (fma -19.6 H (* v v)))) v))
     (atan (fma (/ H (* v v)) 9.8 1.0)))))
double code(double v, double H) {
	double tmp;
	if (v <= -5e+154) {
		tmp = atan(-1.0);
	} else if (v <= 4.9e+33) {
		tmp = atan((sqrt((1.0 / fma(-19.6, H, (v * v)))) * v));
	} else {
		tmp = atan(fma((H / (v * v)), 9.8, 1.0));
	}
	return tmp;
}
function code(v, H)
	tmp = 0.0
	if (v <= -5e+154)
		tmp = atan(-1.0);
	elseif (v <= 4.9e+33)
		tmp = atan(Float64(sqrt(Float64(1.0 / fma(-19.6, H, Float64(v * v)))) * v));
	else
		tmp = atan(fma(Float64(H / Float64(v * v)), 9.8, 1.0));
	end
	return tmp
end
code[v_, H_] := If[LessEqual[v, -5e+154], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 4.9e+33], N[ArcTan[N[(N[Sqrt[N[(1.0 / N[(-19.6 * H + N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * v), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision] * 9.8 + 1.0), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

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

\mathbf{elif}\;v \leq 4.9 \cdot 10^{+33}:\\
\;\;\;\;\tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)\\

\mathbf{else}:\\
\;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(\frac{H}{v \cdot v}, 9.8, 1\right)\right)\\


\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 < 4.90000000000000014e33

      1. Initial program 99.0%

        \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
      2. Add Preprocessing
      3. Taylor expanded in v around 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. Applied rewrites98.9%

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

            \[\leadsto \tan^{-1} \left(\sqrt{{\left(\mathsf{fma}\left(H, -19.6, v \cdot v\right)\right)}^{-1}} \cdot v\right) \]
          2. Step-by-step derivation
            1. Applied rewrites99.1%

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

            if 4.90000000000000014e33 < v

            1. Initial program 50.3%

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

              \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
            4. Step-by-step derivation
              1. Applied rewrites100.0%

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

            Alternative 2: 99.2% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -5 \cdot 10^{+154}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 1.75 \cdot 10^{+72}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, -19.6 \cdot H\right)}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
            (FPCore (v H)
             :precision binary64
             (if (<= v -5e+154)
               (atan -1.0)
               (if (<= v 1.75e+72) (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 <= 1.75e+72) {
            		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 <= 1.75e+72)
            		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, 1.75e+72], 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 1.75 \cdot 10^{+72}:\\
            \;\;\;\;\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 < 1.75000000000000005e72

                1. Initial program 99.1%

                  \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                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. lift-*.f64N/A

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

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

                    \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \color{blue}{\left(2 \cdot \frac{49}{5}\right) \cdot H}}}\right) \]
                  5. pow2N/A

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

                    \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\color{blue}{{v}^{2} + \left(\mathsf{neg}\left(2 \cdot \frac{49}{5}\right)\right) \cdot H}}}\right) \]
                  7. pow2N/A

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

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

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

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

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

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

                if 1.75000000000000005e72 < v

                1. Initial program 43.0%

                  \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                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 3: 89.5% accurate, 1.0× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -1.4 \cdot 10^{-51}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 2.5 \cdot 10^{-90}:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\mathsf{fma}\left(\frac{H}{v}, -9.8, v\right)}\right)\\ \end{array} \end{array} \]
                (FPCore (v H)
                 :precision binary64
                 (if (<= v -1.4e-51)
                   (atan -1.0)
                   (if (<= v 2.5e-90)
                     (atan (* (sqrt (/ -0.05102040816326531 H)) v))
                     (atan (/ v (fma (/ H v) -9.8 v))))))
                double code(double v, double H) {
                	double tmp;
                	if (v <= -1.4e-51) {
                		tmp = atan(-1.0);
                	} else if (v <= 2.5e-90) {
                		tmp = atan((sqrt((-0.05102040816326531 / H)) * v));
                	} else {
                		tmp = atan((v / fma((H / v), -9.8, v)));
                	}
                	return tmp;
                }
                
                function code(v, H)
                	tmp = 0.0
                	if (v <= -1.4e-51)
                		tmp = atan(-1.0);
                	elseif (v <= 2.5e-90)
                		tmp = atan(Float64(sqrt(Float64(-0.05102040816326531 / H)) * v));
                	else
                		tmp = atan(Float64(v / fma(Float64(H / v), -9.8, v)));
                	end
                	return tmp
                end
                
                code[v_, H_] := If[LessEqual[v, -1.4e-51], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 2.5e-90], N[ArcTan[N[(N[Sqrt[N[(-0.05102040816326531 / H), $MachinePrecision]], $MachinePrecision] * v), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(v / N[(N[(H / v), $MachinePrecision] * -9.8 + v), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;v \leq -1.4 \cdot 10^{-51}:\\
                \;\;\;\;\tan^{-1} -1\\
                
                \mathbf{elif}\;v \leq 2.5 \cdot 10^{-90}:\\
                \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\
                
                \mathbf{else}:\\
                \;\;\;\;\tan^{-1} \left(\frac{v}{\mathsf{fma}\left(\frac{H}{v}, -9.8, v\right)}\right)\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 3 regimes
                2. if v < -1.4e-51

                  1. Initial program 49.8%

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

                    \[\leadsto \tan^{-1} \color{blue}{-1} \]
                  4. Step-by-step derivation
                    1. Applied rewrites89.9%

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

                    if -1.4e-51 < v < 2.5000000000000001e-90

                    1. Initial program 98.3%

                      \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                    2. Add Preprocessing
                    3. Taylor expanded in v around 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. Applied rewrites98.2%

                        \[\leadsto \color{blue}{\tan^{-1} \left(\frac{1}{\sqrt{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)} \]
                      2. Step-by-step derivation
                        1. Applied rewrites98.4%

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

                          \[\leadsto \tan^{-1} \left(\sqrt{\frac{\frac{-5}{98}}{H}} \cdot v\right) \]
                        3. Step-by-step derivation
                          1. Applied rewrites95.4%

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

                          if 2.5000000000000001e-90 < v

                          1. Initial program 60.0%

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

                            \[\leadsto \tan^{-1} \left(\frac{v}{\color{blue}{v + \frac{-49}{5} \cdot \frac{H}{v}}}\right) \]
                          4. Step-by-step derivation
                            1. Applied rewrites96.2%

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

                          Alternative 4: 89.3% accurate, 1.0× speedup?

                          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -1.4 \cdot 10^{-51}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 2.5 \cdot 10^{-90}:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(\frac{H}{v \cdot v}, 9.8, 1\right)\right)\\ \end{array} \end{array} \]
                          (FPCore (v H)
                           :precision binary64
                           (if (<= v -1.4e-51)
                             (atan -1.0)
                             (if (<= v 2.5e-90)
                               (atan (* (sqrt (/ -0.05102040816326531 H)) v))
                               (atan (fma (/ H (* v v)) 9.8 1.0)))))
                          double code(double v, double H) {
                          	double tmp;
                          	if (v <= -1.4e-51) {
                          		tmp = atan(-1.0);
                          	} else if (v <= 2.5e-90) {
                          		tmp = atan((sqrt((-0.05102040816326531 / H)) * v));
                          	} else {
                          		tmp = atan(fma((H / (v * v)), 9.8, 1.0));
                          	}
                          	return tmp;
                          }
                          
                          function code(v, H)
                          	tmp = 0.0
                          	if (v <= -1.4e-51)
                          		tmp = atan(-1.0);
                          	elseif (v <= 2.5e-90)
                          		tmp = atan(Float64(sqrt(Float64(-0.05102040816326531 / H)) * v));
                          	else
                          		tmp = atan(fma(Float64(H / Float64(v * v)), 9.8, 1.0));
                          	end
                          	return tmp
                          end
                          
                          code[v_, H_] := If[LessEqual[v, -1.4e-51], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 2.5e-90], N[ArcTan[N[(N[Sqrt[N[(-0.05102040816326531 / H), $MachinePrecision]], $MachinePrecision] * v), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision] * 9.8 + 1.0), $MachinePrecision]], $MachinePrecision]]]
                          
                          \begin{array}{l}
                          
                          \\
                          \begin{array}{l}
                          \mathbf{if}\;v \leq -1.4 \cdot 10^{-51}:\\
                          \;\;\;\;\tan^{-1} -1\\
                          
                          \mathbf{elif}\;v \leq 2.5 \cdot 10^{-90}:\\
                          \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(\frac{H}{v \cdot v}, 9.8, 1\right)\right)\\
                          
                          
                          \end{array}
                          \end{array}
                          
                          Derivation
                          1. Split input into 3 regimes
                          2. if v < -1.4e-51

                            1. Initial program 49.8%

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

                              \[\leadsto \tan^{-1} \color{blue}{-1} \]
                            4. Step-by-step derivation
                              1. Applied rewrites89.9%

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

                              if -1.4e-51 < v < 2.5000000000000001e-90

                              1. Initial program 98.3%

                                \[\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right) \]
                              2. Add Preprocessing
                              3. Taylor expanded in v around 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. Applied rewrites98.2%

                                  \[\leadsto \color{blue}{\tan^{-1} \left(\frac{1}{\sqrt{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)} \]
                                2. Step-by-step derivation
                                  1. Applied rewrites98.4%

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

                                    \[\leadsto \tan^{-1} \left(\sqrt{\frac{\frac{-5}{98}}{H}} \cdot v\right) \]
                                  3. Step-by-step derivation
                                    1. Applied rewrites95.4%

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

                                    if 2.5000000000000001e-90 < v

                                    1. Initial program 60.0%

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

                                      \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
                                    4. Step-by-step derivation
                                      1. Applied rewrites95.9%

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

                                    Alternative 5: 68.1% accurate, 1.3× speedup?

                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -7 \cdot 10^{-308}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
                                    (FPCore (v H) :precision binary64 (if (<= v -7e-308) (atan -1.0) (atan 1.0)))
                                    double code(double v, double H) {
                                    	double tmp;
                                    	if (v <= -7e-308) {
                                    		tmp = atan(-1.0);
                                    	} else {
                                    		tmp = atan(1.0);
                                    	}
                                    	return tmp;
                                    }
                                    
                                    module fmin_fmax_functions
                                        implicit none
                                        private
                                        public fmax
                                        public fmin
                                    
                                        interface fmax
                                            module procedure fmax88
                                            module procedure fmax44
                                            module procedure fmax84
                                            module procedure fmax48
                                        end interface
                                        interface fmin
                                            module procedure fmin88
                                            module procedure fmin44
                                            module procedure fmin84
                                            module procedure fmin48
                                        end interface
                                    contains
                                        real(8) function fmax88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmax44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmax84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmax48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmin44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmin48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                        end function
                                    end module
                                    
                                    real(8) function code(v, h)
                                    use fmin_fmax_functions
                                        real(8), intent (in) :: v
                                        real(8), intent (in) :: h
                                        real(8) :: tmp
                                        if (v <= (-7d-308)) 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 <= -7e-308) {
                                    		tmp = Math.atan(-1.0);
                                    	} else {
                                    		tmp = Math.atan(1.0);
                                    	}
                                    	return tmp;
                                    }
                                    
                                    def code(v, H):
                                    	tmp = 0
                                    	if v <= -7e-308:
                                    		tmp = math.atan(-1.0)
                                    	else:
                                    		tmp = math.atan(1.0)
                                    	return tmp
                                    
                                    function code(v, H)
                                    	tmp = 0.0
                                    	if (v <= -7e-308)
                                    		tmp = atan(-1.0);
                                    	else
                                    		tmp = atan(1.0);
                                    	end
                                    	return tmp
                                    end
                                    
                                    function tmp_2 = code(v, H)
                                    	tmp = 0.0;
                                    	if (v <= -7e-308)
                                    		tmp = atan(-1.0);
                                    	else
                                    		tmp = atan(1.0);
                                    	end
                                    	tmp_2 = tmp;
                                    end
                                    
                                    code[v_, H_] := If[LessEqual[v, -7e-308], N[ArcTan[-1.0], $MachinePrecision], N[ArcTan[1.0], $MachinePrecision]]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \begin{array}{l}
                                    \mathbf{if}\;v \leq -7 \cdot 10^{-308}:\\
                                    \;\;\;\;\tan^{-1} -1\\
                                    
                                    \mathbf{else}:\\
                                    \;\;\;\;\tan^{-1} 1\\
                                    
                                    
                                    \end{array}
                                    \end{array}
                                    
                                    Derivation
                                    1. Split input into 2 regimes
                                    2. if v < -7e-308

                                      1. Initial program 66.0%

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

                                        \[\leadsto \tan^{-1} \color{blue}{-1} \]
                                      4. Step-by-step derivation
                                        1. Applied rewrites65.2%

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

                                        if -7e-308 < v

                                        1. Initial program 69.4%

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

                                          \[\leadsto \tan^{-1} \color{blue}{1} \]
                                        4. Step-by-step derivation
                                          1. Applied rewrites72.3%

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

                                        Alternative 6: 34.3% 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);
                                        }
                                        
                                        module fmin_fmax_functions
                                            implicit none
                                            private
                                            public fmax
                                            public fmin
                                        
                                            interface fmax
                                                module procedure fmax88
                                                module procedure fmax44
                                                module procedure fmax84
                                                module procedure fmax48
                                            end interface
                                            interface fmin
                                                module procedure fmin88
                                                module procedure fmin44
                                                module procedure fmin84
                                                module procedure fmin48
                                            end interface
                                        contains
                                            real(8) function fmax88(x, y) result (res)
                                                real(8), intent (in) :: x
                                                real(8), intent (in) :: y
                                                res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                            end function
                                            real(4) function fmax44(x, y) result (res)
                                                real(4), intent (in) :: x
                                                real(4), intent (in) :: y
                                                res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                            end function
                                            real(8) function fmax84(x, y) result(res)
                                                real(8), intent (in) :: x
                                                real(4), intent (in) :: y
                                                res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                            end function
                                            real(8) function fmax48(x, y) result(res)
                                                real(4), intent (in) :: x
                                                real(8), intent (in) :: y
                                                res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                            end function
                                            real(8) function fmin88(x, y) result (res)
                                                real(8), intent (in) :: x
                                                real(8), intent (in) :: y
                                                res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                            end function
                                            real(4) function fmin44(x, y) result (res)
                                                real(4), intent (in) :: x
                                                real(4), intent (in) :: y
                                                res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                            end function
                                            real(8) function fmin84(x, y) result(res)
                                                real(8), intent (in) :: x
                                                real(4), intent (in) :: y
                                                res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                            end function
                                            real(8) function fmin48(x, y) result(res)
                                                real(4), intent (in) :: x
                                                real(8), intent (in) :: y
                                                res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                            end function
                                        end module
                                        
                                        real(8) function code(v, h)
                                        use fmin_fmax_functions
                                            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 67.7%

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

                                          \[\leadsto \tan^{-1} \color{blue}{-1} \]
                                        4. Step-by-step derivation
                                          1. Applied rewrites33.0%

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

                                          Reproduce

                                          ?
                                          herbie shell --seed 2025025 
                                          (FPCore (v H)
                                            :name "Optimal throwing angle"
                                            :precision binary64
                                            (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H))))))