exp2 (problem 3.3.7)

Percentage Accurate: 52.8% → 99.3%
Time: 9.5s
Alternatives: 9
Speedup: 68.7×

Specification

?
\[\left|x\right| \leq 710\]
\[\begin{array}{l} \\ \left(e^{x} - 2\right) + e^{-x} \end{array} \]
(FPCore (x) :precision binary64 (+ (- (exp x) 2.0) (exp (- x))))
double code(double x) {
	return (exp(x) - 2.0) + exp(-x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (exp(x) - 2.0d0) + exp(-x)
end function
public static double code(double x) {
	return (Math.exp(x) - 2.0) + Math.exp(-x);
}
def code(x):
	return (math.exp(x) - 2.0) + math.exp(-x)
function code(x)
	return Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
end
function tmp = code(x)
	tmp = (exp(x) - 2.0) + exp(-x);
end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(e^{x} - 2\right) + e^{-x}
\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 9 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: 52.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(e^{x} - 2\right) + e^{-x} \end{array} \]
(FPCore (x) :precision binary64 (+ (- (exp x) 2.0) (exp (- x))))
double code(double x) {
	return (exp(x) - 2.0) + exp(-x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (exp(x) - 2.0d0) + exp(-x)
end function
public static double code(double x) {
	return (Math.exp(x) - 2.0) + Math.exp(-x);
}
def code(x):
	return (math.exp(x) - 2.0) + math.exp(-x)
function code(x)
	return Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
end
function tmp = code(x)
	tmp = (exp(x) - 2.0) + exp(-x);
end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(e^{x} - 2\right) + e^{-x}
\end{array}

Alternative 1: 99.3% accurate, 9.0× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  x
  (*
   x
   (+
    1.0
    (*
     x
     (*
      x
      (+
       0.08333333333333333
       (*
        x
        (* x (+ 0.002777777777777778 (* (* x x) 4.96031746031746e-5)))))))))))
double code(double x) {
	return x * (x * (1.0 + (x * (x * (0.08333333333333333 + (x * (x * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5)))))))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x * (x * (1.0d0 + (x * (x * (0.08333333333333333d0 + (x * (x * (0.002777777777777778d0 + ((x * x) * 4.96031746031746d-5)))))))))
end function
public static double code(double x) {
	return x * (x * (1.0 + (x * (x * (0.08333333333333333 + (x * (x * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5)))))))));
}
def code(x):
	return x * (x * (1.0 + (x * (x * (0.08333333333333333 + (x * (x * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5)))))))))
function code(x)
	return Float64(x * Float64(x * Float64(1.0 + Float64(x * Float64(x * Float64(0.08333333333333333 + Float64(x * Float64(x * Float64(0.002777777777777778 + Float64(Float64(x * x) * 4.96031746031746e-5))))))))))
end
function tmp = code(x)
	tmp = x * (x * (1.0 + (x * (x * (0.08333333333333333 + (x * (x * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5)))))))));
end
code[x_] := N[(x * N[(x * N[(1.0 + N[(x * N[(x * N[(0.08333333333333333 + N[(x * N[(x * N[(0.002777777777777778 + N[(N[(x * x), $MachinePrecision] * 4.96031746031746e-5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)}\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right) \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)}\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)}\right)\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{12}} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{12}} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)}\right)\right)\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right) \]
    10. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{360}} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
    11. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{360}} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
    12. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \color{blue}{\left(\frac{1}{20160} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \left({x}^{2} \cdot \color{blue}{\frac{1}{20160}}\right)\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{20160}}\right)\right)\right)\right)\right)\right)\right) \]
    15. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{20160}\right)\right)\right)\right)\right)\right)\right) \]
    16. *-lowering-*.f6499.6%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{20160}\right)\right)\right)\right)\right)\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + \left(x \cdot x\right) \cdot \left(\frac{1}{360} + \left(x \cdot x\right) \cdot \frac{1}{20160}\right)\right)\right)\right)} \]
    2. *-commutativeN/A

      \[\leadsto \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + \left(x \cdot x\right) \cdot \left(\frac{1}{360} + \left(x \cdot x\right) \cdot \frac{1}{20160}\right)\right)\right)\right) \cdot \color{blue}{x} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + \left(x \cdot x\right) \cdot \left(\frac{1}{360} + \left(x \cdot x\right) \cdot \frac{1}{20160}\right)\right)\right)\right), \color{blue}{x}\right) \]
  7. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\left(x \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)\right)\right)\right) \cdot x} \]
  8. Final simplification99.6%

    \[\leadsto x \cdot \left(x \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)\right)\right)\right) \]
  9. Add Preprocessing

Alternative 2: 99.3% accurate, 9.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (* x x)
  (+
   1.0
   (*
    (* x x)
    (+
     0.08333333333333333
     (* (* x x) (+ 0.002777777777777778 (* (* x x) 4.96031746031746e-5))))))))
double code(double x) {
	return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x * x) * (1.0d0 + ((x * x) * (0.08333333333333333d0 + ((x * x) * (0.002777777777777778d0 + ((x * x) * 4.96031746031746d-5))))))
end function
public static double code(double x) {
	return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))));
}
def code(x):
	return (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))))
function code(x)
	return Float64(Float64(x * x) * Float64(1.0 + Float64(Float64(x * x) * Float64(0.08333333333333333 + Float64(Float64(x * x) * Float64(0.002777777777777778 + Float64(Float64(x * x) * 4.96031746031746e-5)))))))
end
function tmp = code(x)
	tmp = (x * x) * (1.0 + ((x * x) * (0.08333333333333333 + ((x * x) * (0.002777777777777778 + ((x * x) * 4.96031746031746e-5))))));
end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(1.0 + N[(N[(x * x), $MachinePrecision] * N[(0.08333333333333333 + N[(N[(x * x), $MachinePrecision] * N[(0.002777777777777778 + N[(N[(x * x), $MachinePrecision] * 4.96031746031746e-5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)}\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right) \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)}\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{12} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)}\right)\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{12}} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{12}} + {x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)\right)}\right)\right)\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{360} + \frac{1}{20160} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right) \]
    10. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{360}} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
    11. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{360}} + \frac{1}{20160} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
    12. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \color{blue}{\left(\frac{1}{20160} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \left({x}^{2} \cdot \color{blue}{\frac{1}{20160}}\right)\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{20160}}\right)\right)\right)\right)\right)\right)\right) \]
    15. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{20160}\right)\right)\right)\right)\right)\right)\right) \]
    16. *-lowering-*.f6499.6%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{360}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{20160}\right)\right)\right)\right)\right)\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot \left(0.002777777777777778 + \left(x \cdot x\right) \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)} \]
  6. Add Preprocessing

Alternative 3: 99.2% accurate, 12.1× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + 0.002777777777777778 \cdot \left(x \cdot x\right)\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (* x x)
  (+
   1.0
   (* x (* x (+ 0.08333333333333333 (* 0.002777777777777778 (* x x))))))))
double code(double x) {
	return (x * x) * (1.0 + (x * (x * (0.08333333333333333 + (0.002777777777777778 * (x * x))))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x * x) * (1.0d0 + (x * (x * (0.08333333333333333d0 + (0.002777777777777778d0 * (x * x))))))
end function
public static double code(double x) {
	return (x * x) * (1.0 + (x * (x * (0.08333333333333333 + (0.002777777777777778 * (x * x))))));
}
def code(x):
	return (x * x) * (1.0 + (x * (x * (0.08333333333333333 + (0.002777777777777778 * (x * x))))))
function code(x)
	return Float64(Float64(x * x) * Float64(1.0 + Float64(x * Float64(x * Float64(0.08333333333333333 + Float64(0.002777777777777778 * Float64(x * x)))))))
end
function tmp = code(x)
	tmp = (x * x) * (1.0 + (x * (x * (0.08333333333333333 + (0.002777777777777778 * (x * x))))));
end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(1.0 + N[(x * N[(x * N[(0.08333333333333333 + N[(0.002777777777777778 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + 0.002777777777777778 \cdot \left(x \cdot x\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} \]
    3. *-commutativeN/A

      \[\leadsto x \cdot \left(\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \cdot \color{blue}{x}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \cdot x\right)}\right) \]
    5. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right) \]
    7. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right)\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{12}} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{12}} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \color{blue}{\left(\frac{1}{360} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right) \]
    12. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left({x}^{2} \cdot \color{blue}{\frac{1}{360}}\right)\right)\right)\right)\right)\right) \]
    13. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left(\left(x \cdot x\right) \cdot \frac{1}{360}\right)\right)\right)\right)\right)\right) \]
    14. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left(x \cdot \color{blue}{\left(x \cdot \frac{1}{360}\right)}\right)\right)\right)\right)\right)\right) \]
    15. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \frac{1}{360}\right)}\right)\right)\right)\right)\right)\right) \]
    16. *-lowering-*.f6499.6%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\frac{1}{360}}\right)\right)\right)\right)\right)\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot 0.002777777777777778\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \left(x \cdot x\right) \cdot \color{blue}{\left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)} \]
    2. *-commutativeN/A

      \[\leadsto \left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left(1 + \left(x \cdot x\right) \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right), \color{blue}{\left(x \cdot x\right)}\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)\right), \left(\color{blue}{x} \cdot x\right)\right) \]
    5. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \left(x \cdot \left(x \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{12} + x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{12}, \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    9. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{12}, \left(\left(x \cdot x\right) \cdot \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    11. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{360}\right)\right)\right)\right)\right), \left(x \cdot x\right)\right) \]
    12. *-lowering-*.f6499.6%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{360}\right)\right)\right)\right)\right), \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  7. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + \left(x \cdot x\right) \cdot 0.002777777777777778\right)\right)\right) \cdot \left(x \cdot x\right)} \]
  8. Final simplification99.6%

    \[\leadsto \left(x \cdot x\right) \cdot \left(1 + x \cdot \left(x \cdot \left(0.08333333333333333 + 0.002777777777777778 \cdot \left(x \cdot x\right)\right)\right)\right) \]
  9. Add Preprocessing

Alternative 4: 99.2% accurate, 12.1× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot 0.002777777777777778\right)\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  x
  (*
   x
   (+
    1.0
    (* (* x x) (+ 0.08333333333333333 (* x (* x 0.002777777777777778))))))))
double code(double x) {
	return x * (x * (1.0 + ((x * x) * (0.08333333333333333 + (x * (x * 0.002777777777777778))))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x * (x * (1.0d0 + ((x * x) * (0.08333333333333333d0 + (x * (x * 0.002777777777777778d0))))))
end function
public static double code(double x) {
	return x * (x * (1.0 + ((x * x) * (0.08333333333333333 + (x * (x * 0.002777777777777778))))));
}
def code(x):
	return x * (x * (1.0 + ((x * x) * (0.08333333333333333 + (x * (x * 0.002777777777777778))))))
function code(x)
	return Float64(x * Float64(x * Float64(1.0 + Float64(Float64(x * x) * Float64(0.08333333333333333 + Float64(x * Float64(x * 0.002777777777777778)))))))
end
function tmp = code(x)
	tmp = x * (x * (1.0 + ((x * x) * (0.08333333333333333 + (x * (x * 0.002777777777777778))))));
end
code[x_] := N[(x * N[(x * N[(1.0 + N[(N[(x * x), $MachinePrecision] * N[(0.08333333333333333 + N[(x * N[(x * 0.002777777777777778), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot 0.002777777777777778\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} \]
    3. *-commutativeN/A

      \[\leadsto x \cdot \left(\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \cdot \color{blue}{x}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) \cdot x\right)}\right) \]
    5. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right) \]
    7. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}\right)\right)\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{12}} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{12}} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \color{blue}{\left(\frac{1}{360} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right) \]
    12. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left({x}^{2} \cdot \color{blue}{\frac{1}{360}}\right)\right)\right)\right)\right)\right) \]
    13. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left(\left(x \cdot x\right) \cdot \frac{1}{360}\right)\right)\right)\right)\right)\right) \]
    14. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \left(x \cdot \color{blue}{\left(x \cdot \frac{1}{360}\right)}\right)\right)\right)\right)\right)\right) \]
    15. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \frac{1}{360}\right)}\right)\right)\right)\right)\right)\right) \]
    16. *-lowering-*.f6499.6%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{12}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\frac{1}{360}}\right)\right)\right)\right)\right)\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot \left(0.08333333333333333 + x \cdot \left(x \cdot 0.002777777777777778\right)\right)\right)\right)} \]
  6. Add Preprocessing

Alternative 5: 99.1% accurate, 15.8× speedup?

\[\begin{array}{l} \\ x \cdot x + \left(x \cdot x\right) \cdot \left(0.08333333333333333 \cdot \left(x \cdot x\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (+ (* x x) (* (* x x) (* 0.08333333333333333 (* x x)))))
double code(double x) {
	return (x * x) + ((x * x) * (0.08333333333333333 * (x * x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x * x) + ((x * x) * (0.08333333333333333d0 * (x * x)))
end function
public static double code(double x) {
	return (x * x) + ((x * x) * (0.08333333333333333 * (x * x)));
}
def code(x):
	return (x * x) + ((x * x) * (0.08333333333333333 * (x * x)))
function code(x)
	return Float64(Float64(x * x) + Float64(Float64(x * x) * Float64(0.08333333333333333 * Float64(x * x))))
end
function tmp = code(x)
	tmp = (x * x) + ((x * x) * (0.08333333333333333 * (x * x)));
end
code[x_] := N[(N[(x * x), $MachinePrecision] + N[(N[(x * x), $MachinePrecision] * N[(0.08333333333333333 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot x + \left(x \cdot x\right) \cdot \left(0.08333333333333333 \cdot \left(x \cdot x\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right) \]
    2. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right) \]
    5. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    8. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right) \]
    9. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right) \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \left(x \cdot x\right) \cdot \color{blue}{\left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right)} \]
    2. +-commutativeN/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12} + \color{blue}{1}\right) \]
    3. distribute-rgt-inN/A

      \[\leadsto \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(x \cdot x\right) + \color{blue}{1 \cdot \left(x \cdot x\right)} \]
    4. *-lft-identityN/A

      \[\leadsto \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(x \cdot x\right) + x \cdot \color{blue}{x} \]
    5. +-lowering-+.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(x \cdot x\right)\right), \color{blue}{\left(x \cdot x\right)}\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right), \left(x \cdot x\right)\right), \left(\color{blue}{x} \cdot x\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right), \left(x \cdot x\right)\right), \left(x \cdot x\right)\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right), \left(x \cdot x\right)\right), \left(x \cdot x\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right), \mathsf{*.f64}\left(x, x\right)\right), \left(x \cdot x\right)\right) \]
    10. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right), \mathsf{*.f64}\left(x, x\right)\right), \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  7. Applied egg-rr99.5%

    \[\leadsto \color{blue}{\left(\left(x \cdot x\right) \cdot 0.08333333333333333\right) \cdot \left(x \cdot x\right) + x \cdot x} \]
  8. Final simplification99.5%

    \[\leadsto x \cdot x + \left(x \cdot x\right) \cdot \left(0.08333333333333333 \cdot \left(x \cdot x\right)\right) \]
  9. Add Preprocessing

Alternative 6: 99.1% accurate, 18.7× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (* (* x x) (+ 1.0 (* 0.08333333333333333 (* x x)))))
double code(double x) {
	return (x * x) * (1.0 + (0.08333333333333333 * (x * x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x * x) * (1.0d0 + (0.08333333333333333d0 * (x * x)))
end function
public static double code(double x) {
	return (x * x) * (1.0 + (0.08333333333333333 * (x * x)));
}
def code(x):
	return (x * x) * (1.0 + (0.08333333333333333 * (x * x)))
function code(x)
	return Float64(Float64(x * x) * Float64(1.0 + Float64(0.08333333333333333 * Float64(x * x))))
end
function tmp = code(x)
	tmp = (x * x) * (1.0 + (0.08333333333333333 * (x * x)));
end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(1.0 + N[(0.08333333333333333 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right) \]
    2. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right) \]
    5. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    8. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right) \]
    9. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right) \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \left(x \cdot x\right) \cdot \color{blue}{\left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right)} \]
    2. *-commutativeN/A

      \[\leadsto \left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right), \color{blue}{\left(x \cdot x\right)}\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right), \left(\color{blue}{x} \cdot x\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right), \left(x \cdot x\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right), \left(x \cdot x\right)\right) \]
    7. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right), \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
  7. Applied egg-rr99.5%

    \[\leadsto \color{blue}{\left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right) \cdot \left(x \cdot x\right)} \]
  8. Final simplification99.5%

    \[\leadsto \left(x \cdot x\right) \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right) \]
  9. Add Preprocessing

Alternative 7: 99.1% accurate, 18.7× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (* x (* x (+ 1.0 (* 0.08333333333333333 (* x x))))))
double code(double x) {
	return x * (x * (1.0 + (0.08333333333333333 * (x * x))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x * (x * (1.0d0 + (0.08333333333333333d0 * (x * x))))
end function
public static double code(double x) {
	return x * (x * (1.0 + (0.08333333333333333 * (x * x))));
}
def code(x):
	return x * (x * (1.0 + (0.08333333333333333 * (x * x))))
function code(x)
	return Float64(x * Float64(x * Float64(1.0 + Float64(0.08333333333333333 * Float64(x * x)))))
end
function tmp = code(x)
	tmp = x * (x * (1.0 + (0.08333333333333333 * (x * x))));
end
code[x_] := N[(x * N[(x * N[(1.0 + N[(0.08333333333333333 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right)\right)
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(x \cdot x\right) \cdot \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right) \]
    2. associate-*l*N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right) \]
    5. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right) \]
    8. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right) \]
    9. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right) \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)\right)} \]
  6. Final simplification99.5%

    \[\leadsto x \cdot \left(x \cdot \left(1 + 0.08333333333333333 \cdot \left(x \cdot x\right)\right)\right) \]
  7. Add Preprocessing

Alternative 8: 98.6% accurate, 68.7× speedup?

\[\begin{array}{l} \\ x \cdot x \end{array} \]
(FPCore (x) :precision binary64 (* x x))
double code(double x) {
	return x * x;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x * x
end function
public static double code(double x) {
	return x * x;
}
def code(x):
	return x * x
function code(x)
	return Float64(x * x)
end
function tmp = code(x)
	tmp = x * x;
end
code[x_] := N[(x * x), $MachinePrecision]
\begin{array}{l}

\\
x \cdot x
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2}} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto x \cdot \color{blue}{x} \]
    2. *-lowering-*.f6499.2%

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{x}\right) \]
  5. Simplified99.2%

    \[\leadsto \color{blue}{x \cdot x} \]
  6. Add Preprocessing

Alternative 9: 5.8% accurate, 206.0× speedup?

\[\begin{array}{l} \\ x \end{array} \]
(FPCore (x) :precision binary64 x)
double code(double x) {
	return x;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x
end function
public static double code(double x) {
	return x;
}
def code(x):
	return x
function code(x)
	return x
end
function tmp = code(x)
	tmp = x;
end
code[x_] := x
\begin{array}{l}

\\
x
\end{array}
Derivation
  1. Initial program 53.5%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \mathsf{+.f64}\left(\mathsf{\_.f64}\left(\mathsf{exp.f64}\left(x\right), 2\right), \color{blue}{1}\right) \]
  4. Step-by-step derivation
    1. Simplified52.3%

      \[\leadsto \left(e^{x} - 2\right) + \color{blue}{1} \]
    2. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x} \]
    3. Step-by-step derivation
      1. Simplified5.8%

        \[\leadsto \color{blue}{x} \]
      2. Add Preprocessing

      Developer Target 1: 99.9% accurate, 1.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sinh \left(\frac{x}{2}\right)\\ 4 \cdot \left(t\_0 \cdot t\_0\right) \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (let* ((t_0 (sinh (/ x 2.0)))) (* 4.0 (* t_0 t_0))))
      double code(double x) {
      	double t_0 = sinh((x / 2.0));
      	return 4.0 * (t_0 * t_0);
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          real(8) :: t_0
          t_0 = sinh((x / 2.0d0))
          code = 4.0d0 * (t_0 * t_0)
      end function
      
      public static double code(double x) {
      	double t_0 = Math.sinh((x / 2.0));
      	return 4.0 * (t_0 * t_0);
      }
      
      def code(x):
      	t_0 = math.sinh((x / 2.0))
      	return 4.0 * (t_0 * t_0)
      
      function code(x)
      	t_0 = sinh(Float64(x / 2.0))
      	return Float64(4.0 * Float64(t_0 * t_0))
      end
      
      function tmp = code(x)
      	t_0 = sinh((x / 2.0));
      	tmp = 4.0 * (t_0 * t_0);
      end
      
      code[x_] := Block[{t$95$0 = N[Sinh[N[(x / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(4.0 * N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \sinh \left(\frac{x}{2}\right)\\
      4 \cdot \left(t\_0 \cdot t\_0\right)
      \end{array}
      \end{array}
      

      Reproduce

      ?
      herbie shell --seed 2024155 
      (FPCore (x)
        :name "exp2 (problem 3.3.7)"
        :precision binary64
        :pre (<= (fabs x) 710.0)
      
        :alt
        (! :herbie-platform default (* 4 (* (sinh (/ x 2)) (sinh (/ x 2)))))
      
        (+ (- (exp x) 2.0) (exp (- x))))