Toniolo and Linder, Equation (7)

Percentage Accurate: 33.3% → 82.5%
Time: 7.0s
Alternatives: 6
Speedup: 3.3×

Specification

?
\[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
(FPCore (x l t)
 :precision binary64
 (/
  (* (sqrt 2.0) t)
  (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))
double code(double x, double l, double t) {
	return (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(x, l, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: l
    real(8), intent (in) :: t
    code = (sqrt(2.0d0) * t) / sqrt(((((x + 1.0d0) / (x - 1.0d0)) * ((l * l) + (2.0d0 * (t * t)))) - (l * l)))
end function
public static double code(double x, double l, double t) {
	return (Math.sqrt(2.0) * t) / Math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
def code(x, l, t):
	return (math.sqrt(2.0) * t) / math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)))
function code(x, l, t)
	return Float64(Float64(sqrt(2.0) * t) / sqrt(Float64(Float64(Float64(Float64(x + 1.0) / Float64(x - 1.0)) * Float64(Float64(l * l) + Float64(2.0 * Float64(t * t)))) - Float64(l * l))))
end
function tmp = code(x, l, t)
	tmp = (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
end
code[x_, l_, t_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * t), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] * N[(N[(l * l), $MachinePrecision] + N[(2.0 * N[(t * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l * l), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}

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: 33.3% accurate, 1.0× speedup?

\[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
(FPCore (x l t)
 :precision binary64
 (/
  (* (sqrt 2.0) t)
  (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))
double code(double x, double l, double t) {
	return (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(x, l, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: l
    real(8), intent (in) :: t
    code = (sqrt(2.0d0) * t) / sqrt(((((x + 1.0d0) / (x - 1.0d0)) * ((l * l) + (2.0d0 * (t * t)))) - (l * l)))
end function
public static double code(double x, double l, double t) {
	return (Math.sqrt(2.0) * t) / Math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
def code(x, l, t):
	return (math.sqrt(2.0) * t) / math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)))
function code(x, l, t)
	return Float64(Float64(sqrt(2.0) * t) / sqrt(Float64(Float64(Float64(Float64(x + 1.0) / Float64(x - 1.0)) * Float64(Float64(l * l) + Float64(2.0 * Float64(t * t)))) - Float64(l * l))))
end
function tmp = code(x, l, t)
	tmp = (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
end
code[x_, l_, t_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * t), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] * N[(N[(l * l), $MachinePrecision] + N[(2.0 * N[(t * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l * l), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}

Alternative 1: 82.5% accurate, 0.2× speedup?

\[\begin{array}{l} t_1 := {\left(\left|t\right|\right)}^{2}\\ t_2 := -1 \cdot t\_1\\ \mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l} \mathbf{if}\;\left|t\right| \leq 5.4 \cdot 10^{+53}:\\ \;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\sqrt{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(2, t\_1 - t\_2, {\ell}^{2}\right) - -1 \cdot {\ell}^{2}}{x}, \mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(t\_2 - t\_1\right)\right)\right) - {\ell}^{2}}{x}, 2 \cdot t\_1\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\ \end{array} \end{array} \]
(FPCore (x l t)
 :precision binary64
 (let* ((t_1 (pow (fabs t) 2.0)) (t_2 (* -1.0 t_1)))
   (*
    (copysign 1.0 t)
    (if (<= (fabs t) 5.4e+53)
      (/
       (* (sqrt 2.0) (fabs t))
       (sqrt
        (fma
         -1.0
         (/
          (-
           (fma
            -1.0
            (/ (- (fma 2.0 (- t_1 t_2) (pow l 2.0)) (* -1.0 (pow l 2.0))) x)
            (fma -1.0 (pow l 2.0) (* 2.0 (- t_2 t_1))))
           (pow l 2.0))
          x)
         (* 2.0 t_1))))
      (sqrt (/ (- x 1.0) (- x -1.0)))))))
double code(double x, double l, double t) {
	double t_1 = pow(fabs(t), 2.0);
	double t_2 = -1.0 * t_1;
	double tmp;
	if (fabs(t) <= 5.4e+53) {
		tmp = (sqrt(2.0) * fabs(t)) / sqrt(fma(-1.0, ((fma(-1.0, ((fma(2.0, (t_1 - t_2), pow(l, 2.0)) - (-1.0 * pow(l, 2.0))) / x), fma(-1.0, pow(l, 2.0), (2.0 * (t_2 - t_1)))) - pow(l, 2.0)) / x), (2.0 * t_1)));
	} else {
		tmp = sqrt(((x - 1.0) / (x - -1.0)));
	}
	return copysign(1.0, t) * tmp;
}
function code(x, l, t)
	t_1 = abs(t) ^ 2.0
	t_2 = Float64(-1.0 * t_1)
	tmp = 0.0
	if (abs(t) <= 5.4e+53)
		tmp = Float64(Float64(sqrt(2.0) * abs(t)) / sqrt(fma(-1.0, Float64(Float64(fma(-1.0, Float64(Float64(fma(2.0, Float64(t_1 - t_2), (l ^ 2.0)) - Float64(-1.0 * (l ^ 2.0))) / x), fma(-1.0, (l ^ 2.0), Float64(2.0 * Float64(t_2 - t_1)))) - (l ^ 2.0)) / x), Float64(2.0 * t_1))));
	else
		tmp = sqrt(Float64(Float64(x - 1.0) / Float64(x - -1.0)));
	end
	return Float64(copysign(1.0, t) * tmp)
end
code[x_, l_, t_] := Block[{t$95$1 = N[Power[N[Abs[t], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$2 = N[(-1.0 * t$95$1), $MachinePrecision]}, N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * If[LessEqual[N[Abs[t], $MachinePrecision], 5.4e+53], N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[Abs[t], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(-1.0 * N[(N[(N[(-1.0 * N[(N[(N[(2.0 * N[(t$95$1 - t$95$2), $MachinePrecision] + N[Power[l, 2.0], $MachinePrecision]), $MachinePrecision] - N[(-1.0 * N[Power[l, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + N[(-1.0 * N[Power[l, 2.0], $MachinePrecision] + N[(2.0 * N[(t$95$2 - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Power[l, 2.0], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + N[(2.0 * t$95$1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(x - 1.0), $MachinePrecision] / N[(x - -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]), $MachinePrecision]]]
\begin{array}{l}
t_1 := {\left(\left|t\right|\right)}^{2}\\
t_2 := -1 \cdot t\_1\\
\mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l}
\mathbf{if}\;\left|t\right| \leq 5.4 \cdot 10^{+53}:\\
\;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\sqrt{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(2, t\_1 - t\_2, {\ell}^{2}\right) - -1 \cdot {\ell}^{2}}{x}, \mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(t\_2 - t\_1\right)\right)\right) - {\ell}^{2}}{x}, 2 \cdot t\_1\right)}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 5.40000000000000039e53

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \color{blue}{\ell \cdot \ell}}} \]
      3. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}}} \]
      4. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      5. lift-+.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \color{blue}{\left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      6. distribute-lft-inN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\left(\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell\right) + \frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      7. associate-+l+N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell\right) + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}}} \]
      8. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \color{blue}{\left(\ell \cdot \ell\right)} + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}} \]
      9. associate-*r*N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell} + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}} \]
      10. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell + \color{blue}{\left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell\right)}}} \]
      11. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \color{blue}{\ell \cdot \ell}\right)}} \]
      12. lower-fma.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(\frac{x + 1}{x - 1} \cdot \ell, \ell, \frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell\right)}}} \]
    3. Applied rewrites32.9%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(\frac{\left(-1 - x\right) \cdot \ell}{1 - x}, \ell, \left(\left(t + t\right) \cdot t\right) \cdot \frac{-1 - x}{1 - x} - \ell \cdot \ell\right)}}} \]
    4. Taylor expanded in x around -inf

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{-1 \cdot \frac{\left(-1 \cdot \frac{\left(2 \cdot \left({t}^{2} - -1 \cdot {t}^{2}\right) + {\ell}^{2}\right) - -1 \cdot {\ell}^{2}}{x} + \left(-1 \cdot {\ell}^{2} + 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right)\right) - {\ell}^{2}}{x} + 2 \cdot {t}^{2}}}} \]
    5. Step-by-step derivation
      1. lower-fma.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{fma}\left(-1, \color{blue}{\frac{\left(-1 \cdot \frac{\left(2 \cdot \left({t}^{2} - -1 \cdot {t}^{2}\right) + {\ell}^{2}\right) - -1 \cdot {\ell}^{2}}{x} + \left(-1 \cdot {\ell}^{2} + 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right)\right) - {\ell}^{2}}{x}}, 2 \cdot {t}^{2}\right)}} \]
    6. Applied rewrites52.1%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(2, {t}^{2} - -1 \cdot {t}^{2}, {\ell}^{2}\right) - -1 \cdot {\ell}^{2}}{x}, \mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right)\right) - {\ell}^{2}}{x}, 2 \cdot {t}^{2}\right)}}} \]

    if 5.40000000000000039e53 < t

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Taylor expanded in t around inf

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lower-+.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lower--.f6439.8%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. Applied rewrites39.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. sqrt-undivN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      8. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(1 + x\right) \cdot \frac{1}{x - 1}\right)}} \]
      9. lift-+.f64N/A

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

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      11. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      12. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      13. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      14. associate-/r*N/A

        \[\leadsto \sqrt{\frac{\frac{2}{2}}{\frac{x + 1}{x - 1}}} \]
      15. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{x - 1}}} \]
      16. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      17. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      18. frac-2negN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      19. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - \left(\mathsf{neg}\left(1\right)\right)\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - -1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      22. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      23. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      24. distribute-frac-neg2N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\frac{-1 - x}{x - 1}\right)}} \]
    6. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
    7. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
      2. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(1\right)}{\frac{-1 - x}{x - 1}}} \]
      3. distribute-frac-negN/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1}{\frac{-1 - x}{x - 1}}\right)} \]
      4. lower-neg.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      5. lift-/.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      6. frac-2negN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      7. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      8. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      9. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      10. div-flip-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      11. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      12. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      13. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      14. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      15. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      16. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      17. lower-/.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      18. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      19. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      22. lower--.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
    8. Applied rewrites39.8%

      \[\leadsto \color{blue}{\sqrt{-\frac{1 - x}{x - -1}}} \]
    9. Step-by-step derivation
      1. lift-neg.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      3. distribute-neg-fracN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      5. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      7. lift--.f6439.8%

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
    10. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 82.3% accurate, 0.3× speedup?

\[\begin{array}{l} t_1 := {\left(\left|t\right|\right)}^{2}\\ \mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l} \mathbf{if}\;\left|t\right| \leq 5.4 \cdot 10^{+53}:\\ \;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\sqrt{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(-1 \cdot t\_1 - t\_1\right)\right) - {\ell}^{2}}{x}, 2 \cdot t\_1\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\ \end{array} \end{array} \]
(FPCore (x l t)
 :precision binary64
 (let* ((t_1 (pow (fabs t) 2.0)))
   (*
    (copysign 1.0 t)
    (if (<= (fabs t) 5.4e+53)
      (/
       (* (sqrt 2.0) (fabs t))
       (sqrt
        (fma
         -1.0
         (/
          (- (fma -1.0 (pow l 2.0) (* 2.0 (- (* -1.0 t_1) t_1))) (pow l 2.0))
          x)
         (* 2.0 t_1))))
      (sqrt (/ (- x 1.0) (- x -1.0)))))))
double code(double x, double l, double t) {
	double t_1 = pow(fabs(t), 2.0);
	double tmp;
	if (fabs(t) <= 5.4e+53) {
		tmp = (sqrt(2.0) * fabs(t)) / sqrt(fma(-1.0, ((fma(-1.0, pow(l, 2.0), (2.0 * ((-1.0 * t_1) - t_1))) - pow(l, 2.0)) / x), (2.0 * t_1)));
	} else {
		tmp = sqrt(((x - 1.0) / (x - -1.0)));
	}
	return copysign(1.0, t) * tmp;
}
function code(x, l, t)
	t_1 = abs(t) ^ 2.0
	tmp = 0.0
	if (abs(t) <= 5.4e+53)
		tmp = Float64(Float64(sqrt(2.0) * abs(t)) / sqrt(fma(-1.0, Float64(Float64(fma(-1.0, (l ^ 2.0), Float64(2.0 * Float64(Float64(-1.0 * t_1) - t_1))) - (l ^ 2.0)) / x), Float64(2.0 * t_1))));
	else
		tmp = sqrt(Float64(Float64(x - 1.0) / Float64(x - -1.0)));
	end
	return Float64(copysign(1.0, t) * tmp)
end
code[x_, l_, t_] := Block[{t$95$1 = N[Power[N[Abs[t], $MachinePrecision], 2.0], $MachinePrecision]}, N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * If[LessEqual[N[Abs[t], $MachinePrecision], 5.4e+53], N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[Abs[t], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(-1.0 * N[(N[(N[(-1.0 * N[Power[l, 2.0], $MachinePrecision] + N[(2.0 * N[(N[(-1.0 * t$95$1), $MachinePrecision] - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Power[l, 2.0], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + N[(2.0 * t$95$1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(x - 1.0), $MachinePrecision] / N[(x - -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
t_1 := {\left(\left|t\right|\right)}^{2}\\
\mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l}
\mathbf{if}\;\left|t\right| \leq 5.4 \cdot 10^{+53}:\\
\;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\sqrt{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(-1 \cdot t\_1 - t\_1\right)\right) - {\ell}^{2}}{x}, 2 \cdot t\_1\right)}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 5.40000000000000039e53

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \color{blue}{\ell \cdot \ell}}} \]
      3. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}}} \]
      4. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      5. lift-+.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \color{blue}{\left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      6. distribute-lft-inN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\left(\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell\right) + \frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right)\right)} + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell}} \]
      7. associate-+l+N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell\right) + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}}} \]
      8. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \color{blue}{\left(\ell \cdot \ell\right)} + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}} \]
      9. associate-*r*N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell} + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) + \left(\mathsf{neg}\left(\ell\right)\right) \cdot \ell\right)}} \]
      10. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell + \color{blue}{\left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell\right)}}} \]
      11. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\left(\frac{x + 1}{x - 1} \cdot \ell\right) \cdot \ell + \left(\frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \color{blue}{\ell \cdot \ell}\right)}} \]
      12. lower-fma.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(\frac{x + 1}{x - 1} \cdot \ell, \ell, \frac{x + 1}{x - 1} \cdot \left(2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell\right)}}} \]
    3. Applied rewrites32.9%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(\frac{\left(-1 - x\right) \cdot \ell}{1 - x}, \ell, \left(\left(t + t\right) \cdot t\right) \cdot \frac{-1 - x}{1 - x} - \ell \cdot \ell\right)}}} \]
    4. Taylor expanded in x around -inf

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{-1 \cdot \frac{\left(-1 \cdot {\ell}^{2} + 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right) - {\ell}^{2}}{x} + 2 \cdot {t}^{2}}}} \]
    5. Step-by-step derivation
      1. lower-fma.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{fma}\left(-1, \color{blue}{\frac{\left(-1 \cdot {\ell}^{2} + 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right) - {\ell}^{2}}{x}}, 2 \cdot {t}^{2}\right)}} \]
    6. Applied rewrites51.8%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{fma}\left(-1, \frac{\mathsf{fma}\left(-1, {\ell}^{2}, 2 \cdot \left(-1 \cdot {t}^{2} - {t}^{2}\right)\right) - {\ell}^{2}}{x}, 2 \cdot {t}^{2}\right)}}} \]

    if 5.40000000000000039e53 < t

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Taylor expanded in t around inf

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lower-+.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lower--.f6439.8%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. Applied rewrites39.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. sqrt-undivN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      8. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(1 + x\right) \cdot \frac{1}{x - 1}\right)}} \]
      9. lift-+.f64N/A

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

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      11. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      12. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      13. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      14. associate-/r*N/A

        \[\leadsto \sqrt{\frac{\frac{2}{2}}{\frac{x + 1}{x - 1}}} \]
      15. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{x - 1}}} \]
      16. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      17. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      18. frac-2negN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      19. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - \left(\mathsf{neg}\left(1\right)\right)\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - -1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      22. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      23. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      24. distribute-frac-neg2N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\frac{-1 - x}{x - 1}\right)}} \]
    6. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
    7. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
      2. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(1\right)}{\frac{-1 - x}{x - 1}}} \]
      3. distribute-frac-negN/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1}{\frac{-1 - x}{x - 1}}\right)} \]
      4. lower-neg.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      5. lift-/.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      6. frac-2negN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      7. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      8. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      9. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      10. div-flip-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      11. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      12. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      13. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      14. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      15. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      16. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      17. lower-/.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      18. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      19. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      22. lower--.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
    8. Applied rewrites39.8%

      \[\leadsto \color{blue}{\sqrt{-\frac{1 - x}{x - -1}}} \]
    9. Step-by-step derivation
      1. lift-neg.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      3. distribute-neg-fracN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      5. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      7. lift--.f6439.8%

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
    10. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 77.4% accurate, 0.9× speedup?

\[\mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l} \mathbf{if}\;\left|t\right| \leq 7.4 \cdot 10^{-233}:\\ \;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\left|\ell\right| \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\ \end{array} \]
(FPCore (x l t)
 :precision binary64
 (*
  (copysign 1.0 t)
  (if (<= (fabs t) 7.4e-233)
    (/
     (* (sqrt 2.0) (fabs t))
     (* (fabs l) (sqrt (/ (- (+ x (* -1.0 (+ 1.0 x))) 1.0) (- 1.0 x)))))
    (sqrt (/ (- x 1.0) (- x -1.0))))))
double code(double x, double l, double t) {
	double tmp;
	if (fabs(t) <= 7.4e-233) {
		tmp = (sqrt(2.0) * fabs(t)) / (fabs(l) * sqrt((((x + (-1.0 * (1.0 + x))) - 1.0) / (1.0 - x))));
	} else {
		tmp = sqrt(((x - 1.0) / (x - -1.0)));
	}
	return copysign(1.0, t) * tmp;
}
public static double code(double x, double l, double t) {
	double tmp;
	if (Math.abs(t) <= 7.4e-233) {
		tmp = (Math.sqrt(2.0) * Math.abs(t)) / (Math.abs(l) * Math.sqrt((((x + (-1.0 * (1.0 + x))) - 1.0) / (1.0 - x))));
	} else {
		tmp = Math.sqrt(((x - 1.0) / (x - -1.0)));
	}
	return Math.copySign(1.0, t) * tmp;
}
def code(x, l, t):
	tmp = 0
	if math.fabs(t) <= 7.4e-233:
		tmp = (math.sqrt(2.0) * math.fabs(t)) / (math.fabs(l) * math.sqrt((((x + (-1.0 * (1.0 + x))) - 1.0) / (1.0 - x))))
	else:
		tmp = math.sqrt(((x - 1.0) / (x - -1.0)))
	return math.copysign(1.0, t) * tmp
function code(x, l, t)
	tmp = 0.0
	if (abs(t) <= 7.4e-233)
		tmp = Float64(Float64(sqrt(2.0) * abs(t)) / Float64(abs(l) * sqrt(Float64(Float64(Float64(x + Float64(-1.0 * Float64(1.0 + x))) - 1.0) / Float64(1.0 - x)))));
	else
		tmp = sqrt(Float64(Float64(x - 1.0) / Float64(x - -1.0)));
	end
	return Float64(copysign(1.0, t) * tmp)
end
function tmp_2 = code(x, l, t)
	tmp = 0.0;
	if (abs(t) <= 7.4e-233)
		tmp = (sqrt(2.0) * abs(t)) / (abs(l) * sqrt((((x + (-1.0 * (1.0 + x))) - 1.0) / (1.0 - x))));
	else
		tmp = sqrt(((x - 1.0) / (x - -1.0)));
	end
	tmp_2 = (sign(t) * abs(1.0)) * tmp;
end
code[x_, l_, t_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * If[LessEqual[N[Abs[t], $MachinePrecision], 7.4e-233], N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[Abs[t], $MachinePrecision]), $MachinePrecision] / N[(N[Abs[l], $MachinePrecision] * N[Sqrt[N[(N[(N[(x + N[(-1.0 * N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision] / N[(1.0 - x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(x - 1.0), $MachinePrecision] / N[(x - -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]), $MachinePrecision]
\mathsf{copysign}\left(1, t\right) \cdot \begin{array}{l}
\mathbf{if}\;\left|t\right| \leq 7.4 \cdot 10^{-233}:\\
\;\;\;\;\frac{\sqrt{2} \cdot \left|t\right|}{\left|\ell\right| \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{x - 1}{x - -1}}\\


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 7.3999999999999996e-233

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}} \]
      2. sub-negate-revN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\mathsf{neg}\left(\left(\ell \cdot \ell - \frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)\right)\right)}}} \]
      3. lift-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{neg}\left(\left(\ell \cdot \ell - \color{blue}{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)}\right)\right)}} \]
      4. lift-/.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{neg}\left(\left(\ell \cdot \ell - \color{blue}{\frac{x + 1}{x - 1}} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)\right)\right)}} \]
      5. associate-*l/N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{neg}\left(\left(\ell \cdot \ell - \color{blue}{\frac{\left(x + 1\right) \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)}{x - 1}}\right)\right)}} \]
      6. sub-to-fractionN/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\mathsf{neg}\left(\color{blue}{\frac{\left(\ell \cdot \ell\right) \cdot \left(x - 1\right) - \left(x + 1\right) \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)}{x - 1}}\right)}} \]
      7. distribute-neg-frac2N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{\left(\ell \cdot \ell\right) \cdot \left(x - 1\right) - \left(x + 1\right) \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}}} \]
      8. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{\left(\ell \cdot \ell\right) \cdot \left(x - 1\right) - \left(x + 1\right) \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}}} \]
    3. Applied rewrites23.4%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\sqrt{\color{blue}{\frac{\mathsf{fma}\left(\ell \cdot \ell, x - 1, \left(-1 - x\right) \cdot \mathsf{fma}\left(t + t, t, \ell \cdot \ell\right)\right)}{1 - x}}}} \]
    4. Taylor expanded in l around inf

      \[\leadsto \frac{\sqrt{2} \cdot t}{\color{blue}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}}} \]
    5. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \color{blue}{\sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}}} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      3. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      4. lower--.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      5. lower-+.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      6. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      7. lower-+.f64N/A

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
      8. lower--.f647.7%

        \[\leadsto \frac{\sqrt{2} \cdot t}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}} \]
    6. Applied rewrites7.7%

      \[\leadsto \frac{\sqrt{2} \cdot t}{\color{blue}{\ell \cdot \sqrt{\frac{\left(x + -1 \cdot \left(1 + x\right)\right) - 1}{1 - x}}}} \]

    if 7.3999999999999996e-233 < t

    1. Initial program 33.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Taylor expanded in t around inf

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lower-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lower-+.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lower--.f6439.8%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. Applied rewrites39.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
      2. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
      3. lift-sqrt.f64N/A

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
      4. sqrt-undivN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      5. lower-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      6. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      7. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
      8. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(1 + x\right) \cdot \frac{1}{x - 1}\right)}} \]
      9. lift-+.f64N/A

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

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      11. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
      12. mult-flipN/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      13. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
      14. associate-/r*N/A

        \[\leadsto \sqrt{\frac{\frac{2}{2}}{\frac{x + 1}{x - 1}}} \]
      15. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{x - 1}}} \]
      16. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      17. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
      18. frac-2negN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      19. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - \left(\mathsf{neg}\left(1\right)\right)\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - -1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      22. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      23. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      24. distribute-frac-neg2N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\frac{-1 - x}{x - 1}\right)}} \]
    6. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
    7. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
      2. metadata-evalN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(1\right)}{\frac{-1 - x}{x - 1}}} \]
      3. distribute-frac-negN/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1}{\frac{-1 - x}{x - 1}}\right)} \]
      4. lower-neg.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      5. lift-/.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
      6. frac-2negN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      7. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
      8. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      9. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
      10. div-flip-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      11. lift--.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
      12. sub-negate-revN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      13. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      14. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      15. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      16. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      17. lower-/.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      18. lift-+.f64N/A

        \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
      19. +-commutativeN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
      20. add-flipN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
      21. metadata-evalN/A

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
      22. lower--.f6439.8%

        \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
    8. Applied rewrites39.8%

      \[\leadsto \color{blue}{\sqrt{-\frac{1 - x}{x - -1}}} \]
    9. Step-by-step derivation
      1. lift-neg.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
      3. distribute-neg-fracN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
      5. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
      7. lift--.f6439.8%

        \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
    10. Applied rewrites39.8%

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 77.2% accurate, 2.3× speedup?

\[\mathsf{copysign}\left(1, t\right) \cdot \sqrt{\frac{x - 1}{x - -1}} \]
(FPCore (x l t)
 :precision binary64
 (* (copysign 1.0 t) (sqrt (/ (- x 1.0) (- x -1.0)))))
double code(double x, double l, double t) {
	return copysign(1.0, t) * sqrt(((x - 1.0) / (x - -1.0)));
}
public static double code(double x, double l, double t) {
	return Math.copySign(1.0, t) * Math.sqrt(((x - 1.0) / (x - -1.0)));
}
def code(x, l, t):
	return math.copysign(1.0, t) * math.sqrt(((x - 1.0) / (x - -1.0)))
function code(x, l, t)
	return Float64(copysign(1.0, t) * sqrt(Float64(Float64(x - 1.0) / Float64(x - -1.0))))
end
function tmp = code(x, l, t)
	tmp = (sign(t) * abs(1.0)) * sqrt(((x - 1.0) / (x - -1.0)));
end
code[x_, l_, t_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * N[Sqrt[N[(N[(x - 1.0), $MachinePrecision] / N[(x - -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\mathsf{copysign}\left(1, t\right) \cdot \sqrt{\frac{x - 1}{x - -1}}
Derivation
  1. Initial program 33.3%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Taylor expanded in t around inf

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    2. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. lower-*.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    5. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    6. lower-+.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    7. lower--.f6439.8%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
  4. Applied rewrites39.8%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  5. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    2. lift-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. lift-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. sqrt-undivN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    5. lower-sqrt.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    6. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    7. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    8. mult-flipN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(1 + x\right) \cdot \frac{1}{x - 1}\right)}} \]
    9. lift-+.f64N/A

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

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
    11. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
    12. mult-flipN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
    13. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
    14. associate-/r*N/A

      \[\leadsto \sqrt{\frac{\frac{2}{2}}{\frac{x + 1}{x - 1}}} \]
    15. metadata-evalN/A

      \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{x - 1}}} \]
    16. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
    17. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
    18. frac-2negN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    19. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    20. add-flipN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - \left(\mathsf{neg}\left(1\right)\right)\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    21. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - -1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    22. sub-negate-revN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    23. lift--.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    24. distribute-frac-neg2N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\frac{-1 - x}{x - 1}\right)}} \]
  6. Applied rewrites39.8%

    \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
  7. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
    2. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(1\right)}{\frac{-1 - x}{x - 1}}} \]
    3. distribute-frac-negN/A

      \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1}{\frac{-1 - x}{x - 1}}\right)} \]
    4. lower-neg.f64N/A

      \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
    5. lift-/.f64N/A

      \[\leadsto \sqrt{-\frac{1}{\frac{-1 - x}{x - 1}}} \]
    6. frac-2negN/A

      \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    7. lift--.f64N/A

      \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    8. sub-negate-revN/A

      \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
    9. lift--.f64N/A

      \[\leadsto \sqrt{-\frac{1}{\frac{\mathsf{neg}\left(\left(-1 - x\right)\right)}{1 - x}}} \]
    10. div-flip-revN/A

      \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
    11. lift--.f64N/A

      \[\leadsto \sqrt{-\frac{1 - x}{\mathsf{neg}\left(\left(-1 - x\right)\right)}} \]
    12. sub-negate-revN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
    13. metadata-evalN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
    14. add-flipN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
    15. +-commutativeN/A

      \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
    16. lift-+.f64N/A

      \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
    17. lower-/.f6439.8%

      \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
    18. lift-+.f64N/A

      \[\leadsto \sqrt{-\frac{1 - x}{1 + x}} \]
    19. +-commutativeN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x + 1}} \]
    20. add-flipN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x - \left(\mathsf{neg}\left(1\right)\right)}} \]
    21. metadata-evalN/A

      \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
    22. lower--.f6439.8%

      \[\leadsto \sqrt{-\frac{1 - x}{x - -1}} \]
  8. Applied rewrites39.8%

    \[\leadsto \color{blue}{\sqrt{-\frac{1 - x}{x - -1}}} \]
  9. Step-by-step derivation
    1. lift-neg.f64N/A

      \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
    2. lift-/.f64N/A

      \[\leadsto \sqrt{\mathsf{neg}\left(\frac{1 - x}{x - -1}\right)} \]
    3. distribute-neg-fracN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(\left(1 - x\right)\right)}{x - -1}} \]
    5. sub-negate-revN/A

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
    6. lower-/.f64N/A

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
    7. lift--.f6439.8%

      \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
  10. Applied rewrites39.8%

    \[\leadsto \sqrt{\frac{x - 1}{x - -1}} \]
  11. Add Preprocessing

Alternative 5: 76.6% accurate, 3.1× speedup?

\[\mathsf{copysign}\left(1, t\right) \cdot \left(1 - \frac{1}{x}\right) \]
(FPCore (x l t) :precision binary64 (* (copysign 1.0 t) (- 1.0 (/ 1.0 x))))
double code(double x, double l, double t) {
	return copysign(1.0, t) * (1.0 - (1.0 / x));
}
public static double code(double x, double l, double t) {
	return Math.copySign(1.0, t) * (1.0 - (1.0 / x));
}
def code(x, l, t):
	return math.copysign(1.0, t) * (1.0 - (1.0 / x))
function code(x, l, t)
	return Float64(copysign(1.0, t) * Float64(1.0 - Float64(1.0 / x)))
end
function tmp = code(x, l, t)
	tmp = (sign(t) * abs(1.0)) * (1.0 - (1.0 / x));
end
code[x_, l_, t_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * N[(1.0 - N[(1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\mathsf{copysign}\left(1, t\right) \cdot \left(1 - \frac{1}{x}\right)
Derivation
  1. Initial program 33.3%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Taylor expanded in t around inf

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    2. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. lower-*.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    5. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    6. lower-+.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    7. lower--.f6439.8%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
  4. Applied rewrites39.8%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  5. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    2. lift-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. lift-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. sqrt-undivN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    5. lower-sqrt.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    6. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    7. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{1 + x}{x - 1}}} \]
    8. mult-flipN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(1 + x\right) \cdot \frac{1}{x - 1}\right)}} \]
    9. lift-+.f64N/A

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

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
    11. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \left(\left(x + 1\right) \cdot \frac{1}{x - 1}\right)}} \]
    12. mult-flipN/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
    13. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{x - 1}}} \]
    14. associate-/r*N/A

      \[\leadsto \sqrt{\frac{\frac{2}{2}}{\frac{x + 1}{x - 1}}} \]
    15. metadata-evalN/A

      \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{x - 1}}} \]
    16. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
    17. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{x + 1}{x - 1}}} \]
    18. frac-2negN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    19. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x + 1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    20. add-flipN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - \left(\mathsf{neg}\left(1\right)\right)\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    21. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{\mathsf{neg}\left(\left(x - -1\right)\right)}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    22. sub-negate-revN/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    23. lift--.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\frac{-1 - x}{\mathsf{neg}\left(\left(x - 1\right)\right)}}} \]
    24. distribute-frac-neg2N/A

      \[\leadsto \sqrt{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\frac{-1 - x}{x - 1}\right)}} \]
  6. Applied rewrites39.8%

    \[\leadsto \sqrt{\frac{-1}{\frac{-1 - x}{x - 1}}} \]
  7. Taylor expanded in x around inf

    \[\leadsto 1 - \color{blue}{\frac{1}{x}} \]
  8. Step-by-step derivation
    1. lower--.f64N/A

      \[\leadsto 1 - \frac{1}{\color{blue}{x}} \]
    2. lower-/.f6439.5%

      \[\leadsto 1 - \frac{1}{x} \]
  9. Applied rewrites39.5%

    \[\leadsto 1 - \color{blue}{\frac{1}{x}} \]
  10. Add Preprocessing

Alternative 6: 75.9% accurate, 3.3× speedup?

\[\mathsf{copysign}\left(1, t\right) \cdot \frac{1.4142135623730951}{\sqrt{2}} \]
(FPCore (x l t)
 :precision binary64
 (* (copysign 1.0 t) (/ 1.4142135623730951 (sqrt 2.0))))
double code(double x, double l, double t) {
	return copysign(1.0, t) * (1.4142135623730951 / sqrt(2.0));
}
public static double code(double x, double l, double t) {
	return Math.copySign(1.0, t) * (1.4142135623730951 / Math.sqrt(2.0));
}
def code(x, l, t):
	return math.copysign(1.0, t) * (1.4142135623730951 / math.sqrt(2.0))
function code(x, l, t)
	return Float64(copysign(1.0, t) * Float64(1.4142135623730951 / sqrt(2.0)))
end
function tmp = code(x, l, t)
	tmp = (sign(t) * abs(1.0)) * (1.4142135623730951 / sqrt(2.0));
end
code[x_, l_, t_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * N[(1.4142135623730951 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\mathsf{copysign}\left(1, t\right) \cdot \frac{1.4142135623730951}{\sqrt{2}}
Derivation
  1. Initial program 33.3%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Taylor expanded in t around inf

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  3. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
    2. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{2 \cdot \frac{1 + x}{x - 1}}}} \]
    3. lower-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    4. lower-*.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    5. lower-/.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    6. lower-+.f64N/A

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
    7. lower--.f6439.8%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}} \]
  4. Applied rewrites39.8%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{2 \cdot \frac{1 + x}{x - 1}}}} \]
  5. Taylor expanded in x around inf

    \[\leadsto \frac{\sqrt{2}}{\sqrt{2}} \]
  6. Step-by-step derivation
    1. Applied rewrites39.1%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2}} \]
    2. Evaluated real constant39.1%

      \[\leadsto \frac{1.4142135623730951}{\sqrt{\color{blue}{2}}} \]
    3. Add Preprocessing

    Reproduce

    ?
    herbie shell --seed 2025183 
    (FPCore (x l t)
      :name "Toniolo and Linder, Equation (7)"
      :precision binary64
      (/ (* (sqrt 2.0) t) (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))