Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, D

Percentage Accurate: 100.0% → 100.0%
Time: 7.3s
Alternatives: 8
Speedup: 1.1×

Specification

?
\[\begin{array}{l} \\ x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* (+ 0.99229 (* x 0.04481)) x)))))
double code(double x) {
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x - ((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + ((0.99229d0 + (x * 0.04481d0)) * x)))
end function
public static double code(double x) {
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
}
def code(x):
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)))
function code(x)
	return Float64(x - Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(Float64(0.99229 + Float64(x * 0.04481)) * x))))
end
function tmp = code(x)
	tmp = x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
end
code[x_] := N[(x - N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(N[(0.99229 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot 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 8 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: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* (+ 0.99229 (* x 0.04481)) x)))))
double code(double x) {
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x - ((2.30753d0 + (x * 0.27061d0)) / (1.0d0 + ((0.99229d0 + (x * 0.04481d0)) * x)))
end function
public static double code(double x) {
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
}
def code(x):
	return x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)))
function code(x)
	return Float64(x - Float64(Float64(2.30753 + Float64(x * 0.27061)) / Float64(1.0 + Float64(Float64(0.99229 + Float64(x * 0.04481)) * x))))
end
function tmp = code(x)
	tmp = x - ((2.30753 + (x * 0.27061)) / (1.0 + ((0.99229 + (x * 0.04481)) * x)));
end
code[x_] := N[(x - N[(N[(2.30753 + N[(x * 0.27061), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(N[(0.99229 + N[(x * 0.04481), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x}
\end{array}

Alternative 1: 100.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ x - \frac{0.27061 \cdot x + 2.30753}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (+ (* 0.27061 x) 2.30753) (+ 1.0 (* (fma 0.04481 x 0.99229) x)))))
double code(double x) {
	return x - (((0.27061 * x) + 2.30753) / (1.0 + (fma(0.04481, x, 0.99229) * x)));
}
function code(x)
	return Float64(x - Float64(Float64(Float64(0.27061 * x) + 2.30753) / Float64(1.0 + Float64(fma(0.04481, x, 0.99229) * x))))
end
code[x_] := N[(x - N[(N[(N[(0.27061 * x), $MachinePrecision] + 2.30753), $MachinePrecision] / N[(1.0 + N[(N[(0.04481 * x + 0.99229), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{0.27061 \cdot x + 2.30753}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    3. lower-+.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\left(0.99229 + x \cdot 0.04481\right) \cdot x + 1}} \]
    4. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right)} \cdot x + 1} \]
    5. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(x \cdot \frac{4481}{100000} + \frac{99229}{100000}\right)} \cdot x + 1} \]
    6. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}\right) \cdot x + 1} \]
    7. *-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}\right) \cdot x + 1} \]
    8. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)} \cdot x + 1} \]
  4. Applied rewrites100.0%

    \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1}} \]
  5. Final simplification100.0%

    \[\leadsto x - \frac{0.27061 \cdot x + 2.30753}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x} \]
  6. Add Preprocessing

Alternative 2: 100.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ x - \frac{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (fma x 0.27061 2.30753) (+ 1.0 (* (fma 0.04481 x 0.99229) x)))))
double code(double x) {
	return x - (fma(x, 0.27061, 2.30753) / (1.0 + (fma(0.04481, x, 0.99229) * x)));
}
function code(x)
	return Float64(x - Float64(fma(x, 0.27061, 2.30753) / Float64(1.0 + Float64(fma(0.04481, x, 0.99229) * x))))
end
code[x_] := N[(x - N[(N[(x * 0.27061 + 2.30753), $MachinePrecision] / N[(1.0 + N[(N[(0.04481 * x + 0.99229), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    3. lower-+.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\left(0.99229 + x \cdot 0.04481\right) \cdot x + 1}} \]
    4. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right)} \cdot x + 1} \]
    5. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(x \cdot \frac{4481}{100000} + \frac{99229}{100000}\right)} \cdot x + 1} \]
    6. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}\right) \cdot x + 1} \]
    7. *-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}\right) \cdot x + 1} \]
    8. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)} \cdot x + 1} \]
  4. Applied rewrites100.0%

    \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1}} \]
  5. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\color{blue}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000} + \frac{230753}{100000}}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000}} + \frac{230753}{100000}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    4. lower-fma.f64100.0

      \[\leadsto x - \frac{\color{blue}{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1} \]
  6. Applied rewrites100.0%

    \[\leadsto x - \frac{\color{blue}{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1} \]
  7. Final simplification100.0%

    \[\leadsto x - \frac{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}{1 + \mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x} \]
  8. Add Preprocessing

Alternative 3: 100.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ x - \frac{0.27061 \cdot x + 2.30753}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (+ (* 0.27061 x) 2.30753) (fma (fma 0.04481 x 0.99229) x 1.0))))
double code(double x) {
	return x - (((0.27061 * x) + 2.30753) / fma(fma(0.04481, x, 0.99229), x, 1.0));
}
function code(x)
	return Float64(x - Float64(Float64(Float64(0.27061 * x) + 2.30753) / fma(fma(0.04481, x, 0.99229), x, 1.0)))
end
code[x_] := N[(x - N[(N[(N[(0.27061 * x), $MachinePrecision] + 2.30753), $MachinePrecision] / N[(N[(0.04481 * x + 0.99229), $MachinePrecision] * x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{0.27061 \cdot x + 2.30753}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} + 1} \]
    4. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.99229 + x \cdot 0.04481, x, 1\right)}} \]
    5. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{\frac{99229}{100000} + x \cdot \frac{4481}{100000}}, x, 1\right)} \]
    6. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000} + \frac{99229}{100000}}, x, 1\right)} \]
    7. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}, x, 1\right)} \]
    8. *-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}, x, 1\right)} \]
    9. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)}, x, 1\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)}} \]
  5. Final simplification100.0%

    \[\leadsto x - \frac{0.27061 \cdot x + 2.30753}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)} \]
  6. Add Preprocessing

Alternative 4: 100.0% accurate, 1.2× speedup?

\[\begin{array}{l} \\ x - \frac{\mathsf{fma}\left(0.27061, x, 2.30753\right)}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (- x (/ (fma 0.27061 x 2.30753) (fma (fma 0.04481 x 0.99229) x 1.0))))
double code(double x) {
	return x - (fma(0.27061, x, 2.30753) / fma(fma(0.04481, x, 0.99229), x, 1.0));
}
function code(x)
	return Float64(x - Float64(fma(0.27061, x, 2.30753) / fma(fma(0.04481, x, 0.99229), x, 1.0)))
end
code[x_] := N[(x - N[(N[(0.27061 * x + 2.30753), $MachinePrecision] / N[(N[(0.04481 * x + 0.99229), $MachinePrecision] * x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{\mathsf{fma}\left(0.27061, x, 2.30753\right)}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\color{blue}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000} + \frac{230753}{100000}}}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000}} + \frac{230753}{100000}}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} \]
    4. *-commutativeN/A

      \[\leadsto x - \frac{\color{blue}{\frac{27061}{100000} \cdot x} + \frac{230753}{100000}}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} \]
    5. lower-fma.f64100.0

      \[\leadsto x - \frac{\color{blue}{\mathsf{fma}\left(0.27061, x, 2.30753\right)}}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
    6. lift-+.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    7. +-commutativeN/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    8. lift-*.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} + 1} \]
    9. lower-fma.f64100.0

      \[\leadsto x - \frac{\mathsf{fma}\left(0.27061, x, 2.30753\right)}{\color{blue}{\mathsf{fma}\left(0.99229 + x \cdot 0.04481, x, 1\right)}} \]
    10. lift-+.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\mathsf{fma}\left(\color{blue}{\frac{99229}{100000} + x \cdot \frac{4481}{100000}}, x, 1\right)} \]
    11. +-commutativeN/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000} + \frac{99229}{100000}}, x, 1\right)} \]
    12. lift-*.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}, x, 1\right)} \]
    13. *-commutativeN/A

      \[\leadsto x - \frac{\mathsf{fma}\left(\frac{27061}{100000}, x, \frac{230753}{100000}\right)}{\mathsf{fma}\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}, x, 1\right)} \]
    14. lower-fma.f64100.0

      \[\leadsto x - \frac{\mathsf{fma}\left(0.27061, x, 2.30753\right)}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)}, x, 1\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{x - \frac{\mathsf{fma}\left(0.27061, x, 2.30753\right)}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)}} \]
  5. Add Preprocessing

Alternative 5: 99.3% accurate, 1.4× speedup?

\[\begin{array}{l} \\ x - \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(-0.025050834237766436, x, 0.37920088514346545\right), x, 0.4333638132548656\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (-
  x
  (/
   1.0
   (fma
    (fma -0.025050834237766436 x 0.37920088514346545)
    x
    0.4333638132548656))))
double code(double x) {
	return x - (1.0 / fma(fma(-0.025050834237766436, x, 0.37920088514346545), x, 0.4333638132548656));
}
function code(x)
	return Float64(x - Float64(1.0 / fma(fma(-0.025050834237766436, x, 0.37920088514346545), x, 0.4333638132548656)))
end
code[x_] := N[(x - N[(1.0 / N[(N[(-0.025050834237766436 * x + 0.37920088514346545), $MachinePrecision] * x + 0.4333638132548656), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(-0.025050834237766436, x, 0.37920088514346545\right), x, 0.4333638132548656\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    3. lower-+.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\left(0.99229 + x \cdot 0.04481\right) \cdot x + 1}} \]
    4. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right)} \cdot x + 1} \]
    5. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(x \cdot \frac{4481}{100000} + \frac{99229}{100000}\right)} \cdot x + 1} \]
    6. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}\right) \cdot x + 1} \]
    7. *-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}\right) \cdot x + 1} \]
    8. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)} \cdot x + 1} \]
  4. Applied rewrites100.0%

    \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1}} \]
  5. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\color{blue}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000} + \frac{230753}{100000}}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\color{blue}{x \cdot \frac{27061}{100000}} + \frac{230753}{100000}}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1} \]
    4. lower-fma.f64100.0

      \[\leadsto x - \frac{\color{blue}{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1} \]
  6. Applied rewrites100.0%

    \[\leadsto x - \frac{\color{blue}{\mathsf{fma}\left(x, 0.27061, 2.30753\right)}}{\mathsf{fma}\left(0.04481, x, 0.99229\right) \cdot x + 1} \]
  7. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto x - \color{blue}{\frac{\mathsf{fma}\left(x, \frac{27061}{100000}, \frac{230753}{100000}\right)}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1}} \]
    2. lift-+.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(x, \frac{27061}{100000}, \frac{230753}{100000}\right)}{\color{blue}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x + 1}} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(x, \frac{27061}{100000}, \frac{230753}{100000}\right)}{\color{blue}{\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right) \cdot x} + 1} \]
    4. lift-fma.f64N/A

      \[\leadsto x - \frac{\mathsf{fma}\left(x, \frac{27061}{100000}, \frac{230753}{100000}\right)}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}} \]
    5. clear-numN/A

      \[\leadsto x - \color{blue}{\frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}{\mathsf{fma}\left(x, \frac{27061}{100000}, \frac{230753}{100000}\right)}}} \]
    6. lift-fma.f64N/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}{\color{blue}{x \cdot \frac{27061}{100000} + \frac{230753}{100000}}}} \]
    7. +-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}{\color{blue}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}} \]
    8. lower-/.f64N/A

      \[\leadsto x - \color{blue}{\frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}} \]
    9. lower-/.f64N/A

      \[\leadsto x - \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}}} \]
    10. lift-fma.f64N/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\color{blue}{\frac{4481}{100000} \cdot x + \frac{99229}{100000}}, x, 1\right)}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}} \]
    11. *-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}, x, 1\right)}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}} \]
    12. lower-fma.f64N/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(x, \frac{4481}{100000}, \frac{99229}{100000}\right)}, x, 1\right)}{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}} \]
    13. +-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(x, \frac{4481}{100000}, \frac{99229}{100000}\right), x, 1\right)}{\color{blue}{x \cdot \frac{27061}{100000} + \frac{230753}{100000}}}} \]
    14. *-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(x, \frac{4481}{100000}, \frac{99229}{100000}\right), x, 1\right)}{\color{blue}{\frac{27061}{100000} \cdot x} + \frac{230753}{100000}}} \]
    15. lower-fma.f64100.0

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(x, 0.04481, 0.99229\right), x, 1\right)}{\color{blue}{\mathsf{fma}\left(0.27061, x, 2.30753\right)}}} \]
  8. Applied rewrites100.0%

    \[\leadsto x - \color{blue}{\frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(x, 0.04481, 0.99229\right), x, 1\right)}{\mathsf{fma}\left(0.27061, x, 2.30753\right)}}} \]
  9. Taylor expanded in x around 0

    \[\leadsto x - \frac{1}{\color{blue}{\frac{100000}{230753} + x \cdot \left(\frac{20191289437}{53246947009} + \frac{-307796913907328}{12286892763167777} \cdot x\right)}} \]
  10. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto x - \frac{1}{\color{blue}{x \cdot \left(\frac{20191289437}{53246947009} + \frac{-307796913907328}{12286892763167777} \cdot x\right) + \frac{100000}{230753}}} \]
    2. *-commutativeN/A

      \[\leadsto x - \frac{1}{\color{blue}{\left(\frac{20191289437}{53246947009} + \frac{-307796913907328}{12286892763167777} \cdot x\right) \cdot x} + \frac{100000}{230753}} \]
    3. lower-fma.f64N/A

      \[\leadsto x - \frac{1}{\color{blue}{\mathsf{fma}\left(\frac{20191289437}{53246947009} + \frac{-307796913907328}{12286892763167777} \cdot x, x, \frac{100000}{230753}\right)}} \]
    4. +-commutativeN/A

      \[\leadsto x - \frac{1}{\mathsf{fma}\left(\color{blue}{\frac{-307796913907328}{12286892763167777} \cdot x + \frac{20191289437}{53246947009}}, x, \frac{100000}{230753}\right)} \]
    5. lower-fma.f6499.0

      \[\leadsto x - \frac{1}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(-0.025050834237766436, x, 0.37920088514346545\right)}, x, 0.4333638132548656\right)} \]
  11. Applied rewrites99.0%

    \[\leadsto x - \frac{1}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(-0.025050834237766436, x, 0.37920088514346545\right), x, 0.4333638132548656\right)}} \]
  12. Add Preprocessing

Alternative 6: 98.7% accurate, 1.9× speedup?

\[\begin{array}{l} \\ x - \frac{2.30753}{\mathsf{fma}\left(0.99229, x, 1\right)} \end{array} \]
(FPCore (x) :precision binary64 (- x (/ 2.30753 (fma 0.99229 x 1.0))))
double code(double x) {
	return x - (2.30753 / fma(0.99229, x, 1.0));
}
function code(x)
	return Float64(x - Float64(2.30753 / fma(0.99229, x, 1.0)))
end
code[x_] := N[(x - N[(2.30753 / N[(0.99229 * x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{2.30753}{\mathsf{fma}\left(0.99229, x, 1\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{1 + \left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x}} \]
    2. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x + 1}} \]
    3. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\color{blue}{\left(\frac{99229}{100000} + x \cdot \frac{4481}{100000}\right) \cdot x} + 1} \]
    4. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(0.99229 + x \cdot 0.04481, x, 1\right)}} \]
    5. lift-+.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{\frac{99229}{100000} + x \cdot \frac{4481}{100000}}, x, 1\right)} \]
    6. +-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000} + \frac{99229}{100000}}, x, 1\right)} \]
    7. lift-*.f64N/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{x \cdot \frac{4481}{100000}} + \frac{99229}{100000}, x, 1\right)} \]
    8. *-commutativeN/A

      \[\leadsto x - \frac{\frac{230753}{100000} + x \cdot \frac{27061}{100000}}{\mathsf{fma}\left(\color{blue}{\frac{4481}{100000} \cdot x} + \frac{99229}{100000}, x, 1\right)} \]
    9. lower-fma.f64100.0

      \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.04481, x, 0.99229\right)}, x, 1\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto x - \frac{2.30753 + x \cdot 0.27061}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)}} \]
  5. Taylor expanded in x around 0

    \[\leadsto x - \frac{\color{blue}{\frac{230753}{100000}}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{4481}{100000}, x, \frac{99229}{100000}\right), x, 1\right)} \]
  6. Step-by-step derivation
    1. Applied rewrites98.3%

      \[\leadsto x - \frac{\color{blue}{2.30753}}{\mathsf{fma}\left(\mathsf{fma}\left(0.04481, x, 0.99229\right), x, 1\right)} \]
    2. Taylor expanded in x around 0

      \[\leadsto x - \frac{\frac{230753}{100000}}{\mathsf{fma}\left(\color{blue}{\frac{99229}{100000}}, x, 1\right)} \]
    3. Step-by-step derivation
      1. Applied rewrites98.3%

        \[\leadsto x - \frac{2.30753}{\mathsf{fma}\left(\color{blue}{0.99229}, x, 1\right)} \]
      2. Add Preprocessing

      Alternative 7: 98.0% accurate, 9.8× speedup?

      \[\begin{array}{l} \\ x - 2.30753 \end{array} \]
      (FPCore (x) :precision binary64 (- x 2.30753))
      double code(double x) {
      	return x - 2.30753;
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          code = x - 2.30753d0
      end function
      
      public static double code(double x) {
      	return x - 2.30753;
      }
      
      def code(x):
      	return x - 2.30753
      
      function code(x)
      	return Float64(x - 2.30753)
      end
      
      function tmp = code(x)
      	tmp = x - 2.30753;
      end
      
      code[x_] := N[(x - 2.30753), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      x - 2.30753
      \end{array}
      
      Derivation
      1. Initial program 100.0%

        \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto x - \color{blue}{\frac{230753}{100000}} \]
      4. Step-by-step derivation
        1. Applied rewrites97.6%

          \[\leadsto x - \color{blue}{2.30753} \]
        2. Add Preprocessing

        Alternative 8: 50.0% accurate, 39.0× speedup?

        \[\begin{array}{l} \\ -2.30753 \end{array} \]
        (FPCore (x) :precision binary64 -2.30753)
        double code(double x) {
        	return -2.30753;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            code = -2.30753d0
        end function
        
        public static double code(double x) {
        	return -2.30753;
        }
        
        def code(x):
        	return -2.30753
        
        function code(x)
        	return -2.30753
        end
        
        function tmp = code(x)
        	tmp = -2.30753;
        end
        
        code[x_] := -2.30753
        
        \begin{array}{l}
        
        \\
        -2.30753
        \end{array}
        
        Derivation
        1. Initial program 100.0%

          \[x - \frac{2.30753 + x \cdot 0.27061}{1 + \left(0.99229 + x \cdot 0.04481\right) \cdot x} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\frac{-230753}{100000}} \]
        4. Step-by-step derivation
          1. Applied rewrites49.2%

            \[\leadsto \color{blue}{-2.30753} \]
          2. Add Preprocessing

          Reproduce

          ?
          herbie shell --seed 2024277 
          (FPCore (x)
            :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, D"
            :precision binary64
            (- x (/ (+ 2.30753 (* x 0.27061)) (+ 1.0 (* (+ 0.99229 (* x 0.04481)) x)))))