Optimal throwing angle

Percentage Accurate: 68.1% → 99.6%
Time: 5.3s
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: 68.1% 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, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -1 \cdot 10^{+154}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 5 \cdot 10^{+131}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
(FPCore (v H)
 :precision binary64
 (if (<= v -1e+154)
   (atan -1.0)
   (if (<= v 5e+131)
     (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H)))))
     (atan 1.0))))
double code(double v, double H) {
	double tmp;
	if (v <= -1e+154) {
		tmp = atan(-1.0);
	} else if (v <= 5e+131) {
		tmp = atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
	} 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 <= (-1d+154)) then
        tmp = atan((-1.0d0))
    else if (v <= 5d+131) then
        tmp = atan((v / sqrt(((v * v) - ((2.0d0 * 9.8d0) * h)))))
    else
        tmp = atan(1.0d0)
    end if
    code = tmp
end function
public static double code(double v, double H) {
	double tmp;
	if (v <= -1e+154) {
		tmp = Math.atan(-1.0);
	} else if (v <= 5e+131) {
		tmp = Math.atan((v / Math.sqrt(((v * v) - ((2.0 * 9.8) * H)))));
	} else {
		tmp = Math.atan(1.0);
	}
	return tmp;
}
def code(v, H):
	tmp = 0
	if v <= -1e+154:
		tmp = math.atan(-1.0)
	elif v <= 5e+131:
		tmp = math.atan((v / math.sqrt(((v * v) - ((2.0 * 9.8) * H)))))
	else:
		tmp = math.atan(1.0)
	return tmp
function code(v, H)
	tmp = 0.0
	if (v <= -1e+154)
		tmp = atan(-1.0);
	elseif (v <= 5e+131)
		tmp = atan(Float64(v / sqrt(Float64(Float64(v * v) - Float64(Float64(2.0 * 9.8) * H)))));
	else
		tmp = atan(1.0);
	end
	return tmp
end
function tmp_2 = code(v, H)
	tmp = 0.0;
	if (v <= -1e+154)
		tmp = atan(-1.0);
	elseif (v <= 5e+131)
		tmp = atan((v / sqrt(((v * v) - ((2.0 * 9.8) * H)))));
	else
		tmp = atan(1.0);
	end
	tmp_2 = tmp;
end
code[v_, H_] := If[LessEqual[v, -1e+154], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 5e+131], N[ArcTan[N[(v / N[Sqrt[N[(N[(v * v), $MachinePrecision] - N[(N[(2.0 * 9.8), $MachinePrecision] * H), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[ArcTan[1.0], $MachinePrecision]]]
\begin{array}{l}

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

\mathbf{elif}\;v \leq 5 \cdot 10^{+131}:\\
\;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{v \cdot v - \left(2 \cdot 9.8\right) \cdot H}}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if v < -1.00000000000000004e154

    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 -1.00000000000000004e154 < v < 4.99999999999999995e131

      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

      if 4.99999999999999995e131 < v

      1. Initial program 19.7%

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

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

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

      Alternative 2: 99.6% accurate, 1.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -1 \cdot 10^{+154}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{elif}\;v \leq 5 \cdot 10^{+131}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, -19.6 \cdot H\right)}}\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
      (FPCore (v H)
       :precision binary64
       (if (<= v -1e+154)
         (atan -1.0)
         (if (<= v 5e+131) (atan (/ v (sqrt (fma v v (* -19.6 H))))) (atan 1.0))))
      double code(double v, double H) {
      	double tmp;
      	if (v <= -1e+154) {
      		tmp = atan(-1.0);
      	} else if (v <= 5e+131) {
      		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 <= -1e+154)
      		tmp = atan(-1.0);
      	elseif (v <= 5e+131)
      		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, -1e+154], N[ArcTan[-1.0], $MachinePrecision], If[LessEqual[v, 5e+131], 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 -1 \cdot 10^{+154}:\\
      \;\;\;\;\tan^{-1} -1\\
      
      \mathbf{elif}\;v \leq 5 \cdot 10^{+131}:\\
      \;\;\;\;\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 < -1.00000000000000004e154

        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 -1.00000000000000004e154 < v < 4.99999999999999995e131

          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. lift-*.f64N/A

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

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

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

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

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

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

              \[\leadsto \tan^{-1} \left(\frac{v}{\sqrt{\mathsf{fma}\left(v, v, \left(\mathsf{neg}\left(\color{blue}{\frac{98}{5}}\right)\right) \cdot H\right)}}\right) \]
            9. 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 4.99999999999999995e131 < v

          1. Initial program 19.7%

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

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

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

          Alternative 3: 88.2% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -9.8 \cdot 10^{-79}:\\ \;\;\;\;\tan^{-1} \left(-9.8 \cdot \frac{H}{v \cdot v} - 1\right)\\ \mathbf{elif}\;v \leq 7.5 \cdot 10^{-54}:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\frac{v}{\mathsf{fma}\left(\frac{H}{v}, -9.8, v\right)}\right)\\ \end{array} \end{array} \]
          (FPCore (v H)
           :precision binary64
           (if (<= v -9.8e-79)
             (atan (- (* -9.8 (/ H (* v v))) 1.0))
             (if (<= v 7.5e-54)
               (atan (* (sqrt (/ -0.05102040816326531 H)) v))
               (atan (/ v (fma (/ H v) -9.8 v))))))
          double code(double v, double H) {
          	double tmp;
          	if (v <= -9.8e-79) {
          		tmp = atan(((-9.8 * (H / (v * v))) - 1.0));
          	} else if (v <= 7.5e-54) {
          		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 <= -9.8e-79)
          		tmp = atan(Float64(Float64(-9.8 * Float64(H / Float64(v * v))) - 1.0));
          	elseif (v <= 7.5e-54)
          		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, -9.8e-79], N[ArcTan[N[(N[(-9.8 * N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]], $MachinePrecision], If[LessEqual[v, 7.5e-54], 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 -9.8 \cdot 10^{-79}:\\
          \;\;\;\;\tan^{-1} \left(-9.8 \cdot \frac{H}{v \cdot v} - 1\right)\\
          
          \mathbf{elif}\;v \leq 7.5 \cdot 10^{-54}:\\
          \;\;\;\;\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 < -9.8000000000000001e-79

            1. Initial program 53.3%

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

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

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

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

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

                \[\leadsto \tan^{-1} \left(\frac{-49}{5} \cdot \frac{H}{\color{blue}{v \cdot v}} - 1\right) \]
              5. lower-*.f6486.9

                \[\leadsto \tan^{-1} \left(-9.8 \cdot \frac{H}{\color{blue}{v \cdot v}} - 1\right) \]
            5. Applied rewrites86.9%

              \[\leadsto \tan^{-1} \color{blue}{\left(-9.8 \cdot \frac{H}{v \cdot v} - 1\right)} \]

            if -9.8000000000000001e-79 < v < 7.5000000000000005e-54

            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. fp-cancel-sub-sign-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. lower-fma.f64N/A

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

                \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(\frac{-98}{5}, H, \color{blue}{v \cdot v}\right)}} \cdot v\right) \]
              11. lower-*.f6499.7

                \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, \color{blue}{v \cdot v}\right)}} \cdot v\right) \]
            5. Applied rewrites99.7%

              \[\leadsto \color{blue}{\tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)} \]
            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 rewrites96.9%

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

              if 7.5000000000000005e-54 < v

              1. Initial program 64.1%

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

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

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

                  \[\leadsto \tan^{-1} \left(\frac{v}{\color{blue}{\mathsf{fma}\left(\frac{H}{v}, \frac{-49}{5}, v\right)}}\right) \]
                4. lower-/.f6485.4

                  \[\leadsto \tan^{-1} \left(\frac{v}{\mathsf{fma}\left(\color{blue}{\frac{H}{v}}, -9.8, v\right)}\right) \]
              5. Applied rewrites85.4%

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

            Alternative 4: 87.9% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{H}{v \cdot v}\\ \mathbf{if}\;v \leq -9.8 \cdot 10^{-79}:\\ \;\;\;\;\tan^{-1} \left(-9.8 \cdot t\_0 - 1\right)\\ \mathbf{elif}\;v \leq 7.5 \cdot 10^{-54}:\\ \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, t\_0, 1\right)\right)\\ \end{array} \end{array} \]
            (FPCore (v H)
             :precision binary64
             (let* ((t_0 (/ H (* v v))))
               (if (<= v -9.8e-79)
                 (atan (- (* -9.8 t_0) 1.0))
                 (if (<= v 7.5e-54)
                   (atan (* (sqrt (/ -0.05102040816326531 H)) v))
                   (atan (fma 9.8 t_0 1.0))))))
            double code(double v, double H) {
            	double t_0 = H / (v * v);
            	double tmp;
            	if (v <= -9.8e-79) {
            		tmp = atan(((-9.8 * t_0) - 1.0));
            	} else if (v <= 7.5e-54) {
            		tmp = atan((sqrt((-0.05102040816326531 / H)) * v));
            	} else {
            		tmp = atan(fma(9.8, t_0, 1.0));
            	}
            	return tmp;
            }
            
            function code(v, H)
            	t_0 = Float64(H / Float64(v * v))
            	tmp = 0.0
            	if (v <= -9.8e-79)
            		tmp = atan(Float64(Float64(-9.8 * t_0) - 1.0));
            	elseif (v <= 7.5e-54)
            		tmp = atan(Float64(sqrt(Float64(-0.05102040816326531 / H)) * v));
            	else
            		tmp = atan(fma(9.8, t_0, 1.0));
            	end
            	return tmp
            end
            
            code[v_, H_] := Block[{t$95$0 = N[(H / N[(v * v), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[v, -9.8e-79], N[ArcTan[N[(N[(-9.8 * t$95$0), $MachinePrecision] - 1.0), $MachinePrecision]], $MachinePrecision], If[LessEqual[v, 7.5e-54], N[ArcTan[N[(N[Sqrt[N[(-0.05102040816326531 / H), $MachinePrecision]], $MachinePrecision] * v), $MachinePrecision]], $MachinePrecision], N[ArcTan[N[(9.8 * t$95$0 + 1.0), $MachinePrecision]], $MachinePrecision]]]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            t_0 := \frac{H}{v \cdot v}\\
            \mathbf{if}\;v \leq -9.8 \cdot 10^{-79}:\\
            \;\;\;\;\tan^{-1} \left(-9.8 \cdot t\_0 - 1\right)\\
            
            \mathbf{elif}\;v \leq 7.5 \cdot 10^{-54}:\\
            \;\;\;\;\tan^{-1} \left(\sqrt{\frac{-0.05102040816326531}{H}} \cdot v\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\tan^{-1} \left(\mathsf{fma}\left(9.8, t\_0, 1\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if v < -9.8000000000000001e-79

              1. Initial program 53.3%

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

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

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

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

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

                  \[\leadsto \tan^{-1} \left(\frac{-49}{5} \cdot \frac{H}{\color{blue}{v \cdot v}} - 1\right) \]
                5. lower-*.f6486.9

                  \[\leadsto \tan^{-1} \left(-9.8 \cdot \frac{H}{\color{blue}{v \cdot v}} - 1\right) \]
              5. Applied rewrites86.9%

                \[\leadsto \tan^{-1} \color{blue}{\left(-9.8 \cdot \frac{H}{v \cdot v} - 1\right)} \]

              if -9.8000000000000001e-79 < v < 7.5000000000000005e-54

              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. fp-cancel-sub-sign-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. lower-fma.f64N/A

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

                  \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(\frac{-98}{5}, H, \color{blue}{v \cdot v}\right)}} \cdot v\right) \]
                11. lower-*.f6499.7

                  \[\leadsto \tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, \color{blue}{v \cdot v}\right)}} \cdot v\right) \]
              5. Applied rewrites99.7%

                \[\leadsto \color{blue}{\tan^{-1} \left(\sqrt{\frac{1}{\mathsf{fma}\left(-19.6, H, v \cdot v\right)}} \cdot v\right)} \]
              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 rewrites96.9%

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

                if 7.5000000000000005e-54 < v

                1. Initial program 64.1%

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

                  \[\leadsto \tan^{-1} \color{blue}{\left(1 + \frac{49}{5} \cdot \frac{H}{{v}^{2}}\right)} \]
                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-*.f6484.6

                    \[\leadsto \tan^{-1} \left(\mathsf{fma}\left(9.8, \frac{H}{\color{blue}{v \cdot v}}, 1\right)\right) \]
                5. Applied rewrites84.6%

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

              Alternative 5: 67.8% accurate, 1.3× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;v \leq -9.8 \cdot 10^{-296}:\\ \;\;\;\;\tan^{-1} -1\\ \mathbf{else}:\\ \;\;\;\;\tan^{-1} 1\\ \end{array} \end{array} \]
              (FPCore (v H) :precision binary64 (if (<= v -9.8e-296) (atan -1.0) (atan 1.0)))
              double code(double v, double H) {
              	double tmp;
              	if (v <= -9.8e-296) {
              		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 <= (-9.8d-296)) 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 <= -9.8e-296) {
              		tmp = Math.atan(-1.0);
              	} else {
              		tmp = Math.atan(1.0);
              	}
              	return tmp;
              }
              
              def code(v, H):
              	tmp = 0
              	if v <= -9.8e-296:
              		tmp = math.atan(-1.0)
              	else:
              		tmp = math.atan(1.0)
              	return tmp
              
              function code(v, H)
              	tmp = 0.0
              	if (v <= -9.8e-296)
              		tmp = atan(-1.0);
              	else
              		tmp = atan(1.0);
              	end
              	return tmp
              end
              
              function tmp_2 = code(v, H)
              	tmp = 0.0;
              	if (v <= -9.8e-296)
              		tmp = atan(-1.0);
              	else
              		tmp = atan(1.0);
              	end
              	tmp_2 = tmp;
              end
              
              code[v_, H_] := If[LessEqual[v, -9.8e-296], N[ArcTan[-1.0], $MachinePrecision], N[ArcTan[1.0], $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;v \leq -9.8 \cdot 10^{-296}:\\
              \;\;\;\;\tan^{-1} -1\\
              
              \mathbf{else}:\\
              \;\;\;\;\tan^{-1} 1\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if v < -9.7999999999999997e-296

                1. Initial program 66.7%

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

                  \[\leadsto \tan^{-1} \color{blue}{-1} \]
                4. Step-by-step derivation
                  1. Applied rewrites62.9%

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

                  if -9.7999999999999997e-296 < v

                  1. Initial program 76.1%

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

                    \[\leadsto \tan^{-1} \color{blue}{1} \]
                  4. Step-by-step derivation
                    1. Applied rewrites58.8%

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

                  Alternative 6: 34.2% 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 71.8%

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

                    \[\leadsto \tan^{-1} \color{blue}{-1} \]
                  4. Step-by-step derivation
                    1. Applied rewrites29.8%

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

                    Reproduce

                    ?
                    herbie shell --seed 2024326 
                    (FPCore (v H)
                      :name "Optimal throwing angle"
                      :precision binary64
                      (atan (/ v (sqrt (- (* v v) (* (* 2.0 9.8) H))))))