Kahan p13 Example 1

Percentage Accurate: 99.9% → 99.8%
Time: 11.9s
Alternatives: 7
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{2 \cdot t}{1 + t}\\ t_2 := t_1 \cdot t_1\\ \frac{1 + t_2}{2 + t_2} \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (let* ((t_1 (/ (* 2.0 t) (+ 1.0 t))) (t_2 (* t_1 t_1)))
   (/ (+ 1.0 t_2) (+ 2.0 t_2))))
double code(double t) {
	double t_1 = (2.0 * t) / (1.0 + t);
	double t_2 = t_1 * t_1;
	return (1.0 + t_2) / (2.0 + t_2);
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: t_1
    real(8) :: t_2
    t_1 = (2.0d0 * t) / (1.0d0 + t)
    t_2 = t_1 * t_1
    code = (1.0d0 + t_2) / (2.0d0 + t_2)
end function
public static double code(double t) {
	double t_1 = (2.0 * t) / (1.0 + t);
	double t_2 = t_1 * t_1;
	return (1.0 + t_2) / (2.0 + t_2);
}
def code(t):
	t_1 = (2.0 * t) / (1.0 + t)
	t_2 = t_1 * t_1
	return (1.0 + t_2) / (2.0 + t_2)
function code(t)
	t_1 = Float64(Float64(2.0 * t) / Float64(1.0 + t))
	t_2 = Float64(t_1 * t_1)
	return Float64(Float64(1.0 + t_2) / Float64(2.0 + t_2))
end
function tmp = code(t)
	t_1 = (2.0 * t) / (1.0 + t);
	t_2 = t_1 * t_1;
	tmp = (1.0 + t_2) / (2.0 + t_2);
end
code[t_] := Block[{t$95$1 = N[(N[(2.0 * t), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * t$95$1), $MachinePrecision]}, N[(N[(1.0 + t$95$2), $MachinePrecision] / N[(2.0 + t$95$2), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{2 \cdot t}{1 + t}\\
t_2 := t_1 \cdot t_1\\
\frac{1 + t_2}{2 + t_2}
\end{array}
\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 7 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: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{2 \cdot t}{1 + t}\\ t_2 := t_1 \cdot t_1\\ \frac{1 + t_2}{2 + t_2} \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (let* ((t_1 (/ (* 2.0 t) (+ 1.0 t))) (t_2 (* t_1 t_1)))
   (/ (+ 1.0 t_2) (+ 2.0 t_2))))
double code(double t) {
	double t_1 = (2.0 * t) / (1.0 + t);
	double t_2 = t_1 * t_1;
	return (1.0 + t_2) / (2.0 + t_2);
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: t_1
    real(8) :: t_2
    t_1 = (2.0d0 * t) / (1.0d0 + t)
    t_2 = t_1 * t_1
    code = (1.0d0 + t_2) / (2.0d0 + t_2)
end function
public static double code(double t) {
	double t_1 = (2.0 * t) / (1.0 + t);
	double t_2 = t_1 * t_1;
	return (1.0 + t_2) / (2.0 + t_2);
}
def code(t):
	t_1 = (2.0 * t) / (1.0 + t)
	t_2 = t_1 * t_1
	return (1.0 + t_2) / (2.0 + t_2)
function code(t)
	t_1 = Float64(Float64(2.0 * t) / Float64(1.0 + t))
	t_2 = Float64(t_1 * t_1)
	return Float64(Float64(1.0 + t_2) / Float64(2.0 + t_2))
end
function tmp = code(t)
	t_1 = (2.0 * t) / (1.0 + t);
	t_2 = t_1 * t_1;
	tmp = (1.0 + t_2) / (2.0 + t_2);
end
code[t_] := Block[{t$95$1 = N[(N[(2.0 * t), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * t$95$1), $MachinePrecision]}, N[(N[(1.0 + t$95$2), $MachinePrecision] / N[(2.0 + t$95$2), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{2 \cdot t}{1 + t}\\
t_2 := t_1 \cdot t_1\\
\frac{1 + t_2}{2 + t_2}
\end{array}
\end{array}

Alternative 1: 99.8% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}\\ \frac{1 + t_1}{t_1 + 2} \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (let* ((t_1 (/ (/ (* t 4.0) (+ 1.0 t)) (/ (+ 1.0 t) t))))
   (/ (+ 1.0 t_1) (+ t_1 2.0))))
double code(double t) {
	double t_1 = ((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t);
	return (1.0 + t_1) / (t_1 + 2.0);
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: t_1
    t_1 = ((t * 4.0d0) / (1.0d0 + t)) / ((1.0d0 + t) / t)
    code = (1.0d0 + t_1) / (t_1 + 2.0d0)
end function
public static double code(double t) {
	double t_1 = ((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t);
	return (1.0 + t_1) / (t_1 + 2.0);
}
def code(t):
	t_1 = ((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t)
	return (1.0 + t_1) / (t_1 + 2.0)
function code(t)
	t_1 = Float64(Float64(Float64(t * 4.0) / Float64(1.0 + t)) / Float64(Float64(1.0 + t) / t))
	return Float64(Float64(1.0 + t_1) / Float64(t_1 + 2.0))
end
function tmp = code(t)
	t_1 = ((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t);
	tmp = (1.0 + t_1) / (t_1 + 2.0);
end
code[t_] := Block[{t$95$1 = N[(N[(N[(t * 4.0), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision] / N[(N[(1.0 + t), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 + t$95$1), $MachinePrecision] / N[(t$95$1 + 2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}\\
\frac{1 + t_1}{t_1 + 2}
\end{array}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
  2. Step-by-step derivation
    1. associate-/l*100.0%

      \[\leadsto \frac{1 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. associate-/l*100.0%

      \[\leadsto \frac{1 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    3. associate-/l*100.0%

      \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}} \]
    4. associate-/l*100.0%

      \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. associate-*l/100.0%

      \[\leadsto \frac{1 + \color{blue}{\frac{2 \cdot \frac{2}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    2. associate-*r/100.0%

      \[\leadsto \frac{1 + \frac{\color{blue}{\frac{2 \cdot 2}{\frac{1 + t}{t}}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    3. metadata-eval100.0%

      \[\leadsto \frac{1 + \frac{\frac{\color{blue}{4}}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    4. associate-/l*100.0%

      \[\leadsto \frac{1 + \frac{\color{blue}{\frac{4 \cdot t}{1 + t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    5. *-commutative100.0%

      \[\leadsto \frac{1 + \frac{\frac{\color{blue}{t \cdot 4}}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
  6. Applied egg-rr100.0%

    \[\leadsto \frac{1 + \color{blue}{\frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
  7. Step-by-step derivation
    1. associate-*l/100.0%

      \[\leadsto \frac{1 + \color{blue}{\frac{2 \cdot \frac{2}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    2. associate-*r/100.0%

      \[\leadsto \frac{1 + \frac{\color{blue}{\frac{2 \cdot 2}{\frac{1 + t}{t}}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    3. metadata-eval100.0%

      \[\leadsto \frac{1 + \frac{\frac{\color{blue}{4}}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    4. associate-/l*100.0%

      \[\leadsto \frac{1 + \frac{\color{blue}{\frac{4 \cdot t}{1 + t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    5. *-commutative100.0%

      \[\leadsto \frac{1 + \frac{\frac{\color{blue}{t \cdot 4}}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
  8. Applied egg-rr100.0%

    \[\leadsto \frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \color{blue}{\frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}} \]
  9. Final simplification100.0%

    \[\leadsto \frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{\frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}} + 2} \]
  10. Add Preprocessing

Alternative 2: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}\\ \mathbf{if}\;t \leq -1000000000 \lor \neg \left(t \leq 20000000\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + t_1}{2 + t_1}\\ \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (let* ((t_1 (/ (* t (* t 4.0)) (* (+ 1.0 t) (+ 1.0 t)))))
   (if (or (<= t -1000000000.0) (not (<= t 20000000.0)))
     (- 0.8333333333333334 (/ 0.2222222222222222 t))
     (/ (+ 1.0 t_1) (+ 2.0 t_1)))))
double code(double t) {
	double t_1 = (t * (t * 4.0)) / ((1.0 + t) * (1.0 + t));
	double tmp;
	if ((t <= -1000000000.0) || !(t <= 20000000.0)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + t_1) / (2.0 + t_1);
	}
	return tmp;
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: t_1
    real(8) :: tmp
    t_1 = (t * (t * 4.0d0)) / ((1.0d0 + t) * (1.0d0 + t))
    if ((t <= (-1000000000.0d0)) .or. (.not. (t <= 20000000.0d0))) then
        tmp = 0.8333333333333334d0 - (0.2222222222222222d0 / t)
    else
        tmp = (1.0d0 + t_1) / (2.0d0 + t_1)
    end if
    code = tmp
end function
public static double code(double t) {
	double t_1 = (t * (t * 4.0)) / ((1.0 + t) * (1.0 + t));
	double tmp;
	if ((t <= -1000000000.0) || !(t <= 20000000.0)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + t_1) / (2.0 + t_1);
	}
	return tmp;
}
def code(t):
	t_1 = (t * (t * 4.0)) / ((1.0 + t) * (1.0 + t))
	tmp = 0
	if (t <= -1000000000.0) or not (t <= 20000000.0):
		tmp = 0.8333333333333334 - (0.2222222222222222 / t)
	else:
		tmp = (1.0 + t_1) / (2.0 + t_1)
	return tmp
function code(t)
	t_1 = Float64(Float64(t * Float64(t * 4.0)) / Float64(Float64(1.0 + t) * Float64(1.0 + t)))
	tmp = 0.0
	if ((t <= -1000000000.0) || !(t <= 20000000.0))
		tmp = Float64(0.8333333333333334 - Float64(0.2222222222222222 / t));
	else
		tmp = Float64(Float64(1.0 + t_1) / Float64(2.0 + t_1));
	end
	return tmp
end
function tmp_2 = code(t)
	t_1 = (t * (t * 4.0)) / ((1.0 + t) * (1.0 + t));
	tmp = 0.0;
	if ((t <= -1000000000.0) || ~((t <= 20000000.0)))
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	else
		tmp = (1.0 + t_1) / (2.0 + t_1);
	end
	tmp_2 = tmp;
end
code[t_] := Block[{t$95$1 = N[(N[(t * N[(t * 4.0), $MachinePrecision]), $MachinePrecision] / N[(N[(1.0 + t), $MachinePrecision] * N[(1.0 + t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t, -1000000000.0], N[Not[LessEqual[t, 20000000.0]], $MachinePrecision]], N[(0.8333333333333334 - N[(0.2222222222222222 / t), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + t$95$1), $MachinePrecision] / N[(2.0 + t$95$1), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}\\
\mathbf{if}\;t \leq -1000000000 \lor \neg \left(t \leq 20000000\right):\\
\;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + t_1}{2 + t_1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -1e9 or 2e7 < t

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac58.7%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out58.7%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*58.7%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval58.7%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac58.7%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified58.7%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 100.0%

      \[\leadsto \color{blue}{0.8333333333333334 - 0.2222222222222222 \cdot \frac{1}{t}} \]
    6. Step-by-step derivation
      1. associate-*r/100.0%

        \[\leadsto 0.8333333333333334 - \color{blue}{\frac{0.2222222222222222 \cdot 1}{t}} \]
      2. metadata-eval100.0%

        \[\leadsto 0.8333333333333334 - \frac{\color{blue}{0.2222222222222222}}{t} \]
    7. Simplified100.0%

      \[\leadsto \color{blue}{0.8333333333333334 - \frac{0.2222222222222222}{t}} \]

    if -1e9 < t < 2e7

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac99.9%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out99.9%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*99.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval99.9%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac100.0%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -1000000000 \lor \neg \left(t \leq 20000000\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 99.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{1 + t}{t}\\ \mathbf{if}\;t \leq -0.5 \lor \neg \left(t \leq 0.74\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{t_1}}{2 + \frac{2}{t_1} \cdot \left(t \cdot 2\right)}\\ \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (let* ((t_1 (/ (+ 1.0 t) t)))
   (if (or (<= t -0.5) (not (<= t 0.74)))
     (- 0.8333333333333334 (/ 0.2222222222222222 t))
     (/
      (+ 1.0 (/ (/ (* t 4.0) (+ 1.0 t)) t_1))
      (+ 2.0 (* (/ 2.0 t_1) (* t 2.0)))))))
double code(double t) {
	double t_1 = (1.0 + t) / t;
	double tmp;
	if ((t <= -0.5) || !(t <= 0.74)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / t_1)) / (2.0 + ((2.0 / t_1) * (t * 2.0)));
	}
	return tmp;
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: t_1
    real(8) :: tmp
    t_1 = (1.0d0 + t) / t
    if ((t <= (-0.5d0)) .or. (.not. (t <= 0.74d0))) then
        tmp = 0.8333333333333334d0 - (0.2222222222222222d0 / t)
    else
        tmp = (1.0d0 + (((t * 4.0d0) / (1.0d0 + t)) / t_1)) / (2.0d0 + ((2.0d0 / t_1) * (t * 2.0d0)))
    end if
    code = tmp
end function
public static double code(double t) {
	double t_1 = (1.0 + t) / t;
	double tmp;
	if ((t <= -0.5) || !(t <= 0.74)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / t_1)) / (2.0 + ((2.0 / t_1) * (t * 2.0)));
	}
	return tmp;
}
def code(t):
	t_1 = (1.0 + t) / t
	tmp = 0
	if (t <= -0.5) or not (t <= 0.74):
		tmp = 0.8333333333333334 - (0.2222222222222222 / t)
	else:
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / t_1)) / (2.0 + ((2.0 / t_1) * (t * 2.0)))
	return tmp
function code(t)
	t_1 = Float64(Float64(1.0 + t) / t)
	tmp = 0.0
	if ((t <= -0.5) || !(t <= 0.74))
		tmp = Float64(0.8333333333333334 - Float64(0.2222222222222222 / t));
	else
		tmp = Float64(Float64(1.0 + Float64(Float64(Float64(t * 4.0) / Float64(1.0 + t)) / t_1)) / Float64(2.0 + Float64(Float64(2.0 / t_1) * Float64(t * 2.0))));
	end
	return tmp
end
function tmp_2 = code(t)
	t_1 = (1.0 + t) / t;
	tmp = 0.0;
	if ((t <= -0.5) || ~((t <= 0.74)))
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	else
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / t_1)) / (2.0 + ((2.0 / t_1) * (t * 2.0)));
	end
	tmp_2 = tmp;
end
code[t_] := Block[{t$95$1 = N[(N[(1.0 + t), $MachinePrecision] / t), $MachinePrecision]}, If[Or[LessEqual[t, -0.5], N[Not[LessEqual[t, 0.74]], $MachinePrecision]], N[(0.8333333333333334 - N[(0.2222222222222222 / t), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + N[(N[(N[(t * 4.0), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision] / t$95$1), $MachinePrecision]), $MachinePrecision] / N[(2.0 + N[(N[(2.0 / t$95$1), $MachinePrecision] * N[(t * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{1 + t}{t}\\
\mathbf{if}\;t \leq -0.5 \lor \neg \left(t \leq 0.74\right):\\
\;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{t_1}}{2 + \frac{2}{t_1} \cdot \left(t \cdot 2\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -0.5 or 0.73999999999999999 < t

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac60.2%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval60.2%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac60.3%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified60.3%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - 0.2222222222222222 \cdot \frac{1}{t}} \]
    6. Step-by-step derivation
      1. associate-*r/98.4%

        \[\leadsto 0.8333333333333334 - \color{blue}{\frac{0.2222222222222222 \cdot 1}{t}} \]
      2. metadata-eval98.4%

        \[\leadsto 0.8333333333333334 - \frac{\color{blue}{0.2222222222222222}}{t} \]
    7. Simplified98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - \frac{0.2222222222222222}{t}} \]

    if -0.5 < t < 0.73999999999999999

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. associate-/l*100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}} \]
      4. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. associate-*l/100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{2 \cdot \frac{2}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      2. associate-*r/100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\frac{2 \cdot 2}{\frac{1 + t}{t}}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      3. metadata-eval100.0%

        \[\leadsto \frac{1 + \frac{\frac{\color{blue}{4}}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      4. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\frac{4 \cdot t}{1 + t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      5. *-commutative100.0%

        \[\leadsto \frac{1 + \frac{\frac{\color{blue}{t \cdot 4}}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    6. Applied egg-rr100.0%

      \[\leadsto \frac{1 + \color{blue}{\frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    7. Taylor expanded in t around 0 99.8%

      \[\leadsto \frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \color{blue}{\left(2 \cdot t\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -0.5 \lor \neg \left(t \leq 0.74\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \left(t \cdot 2\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 99.0% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -0.45 \lor \neg \left(t \leq 0.59\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \left(t \cdot 2\right) \cdot \left(t \cdot 2\right)}\\ \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (if (or (<= t -0.45) (not (<= t 0.59)))
   (- 0.8333333333333334 (/ 0.2222222222222222 t))
   (/
    (+ 1.0 (/ (/ (* t 4.0) (+ 1.0 t)) (/ (+ 1.0 t) t)))
    (+ 2.0 (* (* t 2.0) (* t 2.0))))))
double code(double t) {
	double tmp;
	if ((t <= -0.45) || !(t <= 0.59)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t))) / (2.0 + ((t * 2.0) * (t * 2.0)));
	}
	return tmp;
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: tmp
    if ((t <= (-0.45d0)) .or. (.not. (t <= 0.59d0))) then
        tmp = 0.8333333333333334d0 - (0.2222222222222222d0 / t)
    else
        tmp = (1.0d0 + (((t * 4.0d0) / (1.0d0 + t)) / ((1.0d0 + t) / t))) / (2.0d0 + ((t * 2.0d0) * (t * 2.0d0)))
    end if
    code = tmp
end function
public static double code(double t) {
	double tmp;
	if ((t <= -0.45) || !(t <= 0.59)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t))) / (2.0 + ((t * 2.0) * (t * 2.0)));
	}
	return tmp;
}
def code(t):
	tmp = 0
	if (t <= -0.45) or not (t <= 0.59):
		tmp = 0.8333333333333334 - (0.2222222222222222 / t)
	else:
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t))) / (2.0 + ((t * 2.0) * (t * 2.0)))
	return tmp
function code(t)
	tmp = 0.0
	if ((t <= -0.45) || !(t <= 0.59))
		tmp = Float64(0.8333333333333334 - Float64(0.2222222222222222 / t));
	else
		tmp = Float64(Float64(1.0 + Float64(Float64(Float64(t * 4.0) / Float64(1.0 + t)) / Float64(Float64(1.0 + t) / t))) / Float64(2.0 + Float64(Float64(t * 2.0) * Float64(t * 2.0))));
	end
	return tmp
end
function tmp_2 = code(t)
	tmp = 0.0;
	if ((t <= -0.45) || ~((t <= 0.59)))
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	else
		tmp = (1.0 + (((t * 4.0) / (1.0 + t)) / ((1.0 + t) / t))) / (2.0 + ((t * 2.0) * (t * 2.0)));
	end
	tmp_2 = tmp;
end
code[t_] := If[Or[LessEqual[t, -0.45], N[Not[LessEqual[t, 0.59]], $MachinePrecision]], N[(0.8333333333333334 - N[(0.2222222222222222 / t), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + N[(N[(N[(t * 4.0), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision] / N[(N[(1.0 + t), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(2.0 + N[(N[(t * 2.0), $MachinePrecision] * N[(t * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.45 \lor \neg \left(t \leq 0.59\right):\\
\;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \left(t \cdot 2\right) \cdot \left(t \cdot 2\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -0.450000000000000011 or 0.589999999999999969 < t

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac60.2%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval60.2%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac60.3%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified60.3%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - 0.2222222222222222 \cdot \frac{1}{t}} \]
    6. Step-by-step derivation
      1. associate-*r/98.4%

        \[\leadsto 0.8333333333333334 - \color{blue}{\frac{0.2222222222222222 \cdot 1}{t}} \]
      2. metadata-eval98.4%

        \[\leadsto 0.8333333333333334 - \frac{\color{blue}{0.2222222222222222}}{t} \]
    7. Simplified98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - \frac{0.2222222222222222}{t}} \]

    if -0.450000000000000011 < t < 0.589999999999999969

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. associate-/l*100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \color{blue}{\frac{2}{\frac{1 + t}{t}}}} \]
      4. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \color{blue}{\frac{2}{\frac{1 + t}{t}}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. associate-*l/100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{2 \cdot \frac{2}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      2. associate-*r/100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\frac{2 \cdot 2}{\frac{1 + t}{t}}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      3. metadata-eval100.0%

        \[\leadsto \frac{1 + \frac{\frac{\color{blue}{4}}{\frac{1 + t}{t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      4. associate-/l*100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\frac{4 \cdot t}{1 + t}}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
      5. *-commutative100.0%

        \[\leadsto \frac{1 + \frac{\frac{\color{blue}{t \cdot 4}}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    6. Applied egg-rr100.0%

      \[\leadsto \frac{1 + \color{blue}{\frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \frac{2}{\frac{1 + t}{t}}} \]
    7. Taylor expanded in t around 0 99.8%

      \[\leadsto \frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \frac{2}{\frac{1 + t}{t}} \cdot \color{blue}{\left(2 \cdot t\right)}} \]
    8. Taylor expanded in t around 0 99.8%

      \[\leadsto \frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \color{blue}{\left(2 \cdot t\right)} \cdot \left(2 \cdot t\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -0.45 \lor \neg \left(t \leq 0.59\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{\frac{t \cdot 4}{1 + t}}{\frac{1 + t}{t}}}{2 + \left(t \cdot 2\right) \cdot \left(t \cdot 2\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 98.8% accurate, 3.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -0.49 \lor \neg \left(t \leq 0.67\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;0.5\\ \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (if (or (<= t -0.49) (not (<= t 0.67)))
   (- 0.8333333333333334 (/ 0.2222222222222222 t))
   0.5))
double code(double t) {
	double tmp;
	if ((t <= -0.49) || !(t <= 0.67)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = 0.5;
	}
	return tmp;
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: tmp
    if ((t <= (-0.49d0)) .or. (.not. (t <= 0.67d0))) then
        tmp = 0.8333333333333334d0 - (0.2222222222222222d0 / t)
    else
        tmp = 0.5d0
    end if
    code = tmp
end function
public static double code(double t) {
	double tmp;
	if ((t <= -0.49) || !(t <= 0.67)) {
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	} else {
		tmp = 0.5;
	}
	return tmp;
}
def code(t):
	tmp = 0
	if (t <= -0.49) or not (t <= 0.67):
		tmp = 0.8333333333333334 - (0.2222222222222222 / t)
	else:
		tmp = 0.5
	return tmp
function code(t)
	tmp = 0.0
	if ((t <= -0.49) || !(t <= 0.67))
		tmp = Float64(0.8333333333333334 - Float64(0.2222222222222222 / t));
	else
		tmp = 0.5;
	end
	return tmp
end
function tmp_2 = code(t)
	tmp = 0.0;
	if ((t <= -0.49) || ~((t <= 0.67)))
		tmp = 0.8333333333333334 - (0.2222222222222222 / t);
	else
		tmp = 0.5;
	end
	tmp_2 = tmp;
end
code[t_] := If[Or[LessEqual[t, -0.49], N[Not[LessEqual[t, 0.67]], $MachinePrecision]], N[(0.8333333333333334 - N[(0.2222222222222222 / t), $MachinePrecision]), $MachinePrecision], 0.5]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.49 \lor \neg \left(t \leq 0.67\right):\\
\;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\

\mathbf{else}:\\
\;\;\;\;0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -0.48999999999999999 or 0.67000000000000004 < t

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac60.2%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval60.2%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac60.3%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified60.3%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - 0.2222222222222222 \cdot \frac{1}{t}} \]
    6. Step-by-step derivation
      1. associate-*r/98.4%

        \[\leadsto 0.8333333333333334 - \color{blue}{\frac{0.2222222222222222 \cdot 1}{t}} \]
      2. metadata-eval98.4%

        \[\leadsto 0.8333333333333334 - \frac{\color{blue}{0.2222222222222222}}{t} \]
    7. Simplified98.4%

      \[\leadsto \color{blue}{0.8333333333333334 - \frac{0.2222222222222222}{t}} \]

    if -0.48999999999999999 < t < 0.67000000000000004

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out100.0%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval100.0%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac100.0%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around 0 99.4%

      \[\leadsto \color{blue}{0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -0.49 \lor \neg \left(t \leq 0.67\right):\\ \;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\ \mathbf{else}:\\ \;\;\;\;0.5\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 98.2% accurate, 6.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -0.34:\\ \;\;\;\;0.8333333333333334\\ \mathbf{elif}\;t \leq 1:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;0.8333333333333334\\ \end{array} \end{array} \]
(FPCore (t)
 :precision binary64
 (if (<= t -0.34) 0.8333333333333334 (if (<= t 1.0) 0.5 0.8333333333333334)))
double code(double t) {
	double tmp;
	if (t <= -0.34) {
		tmp = 0.8333333333333334;
	} else if (t <= 1.0) {
		tmp = 0.5;
	} else {
		tmp = 0.8333333333333334;
	}
	return tmp;
}
real(8) function code(t)
    real(8), intent (in) :: t
    real(8) :: tmp
    if (t <= (-0.34d0)) then
        tmp = 0.8333333333333334d0
    else if (t <= 1.0d0) then
        tmp = 0.5d0
    else
        tmp = 0.8333333333333334d0
    end if
    code = tmp
end function
public static double code(double t) {
	double tmp;
	if (t <= -0.34) {
		tmp = 0.8333333333333334;
	} else if (t <= 1.0) {
		tmp = 0.5;
	} else {
		tmp = 0.8333333333333334;
	}
	return tmp;
}
def code(t):
	tmp = 0
	if t <= -0.34:
		tmp = 0.8333333333333334
	elif t <= 1.0:
		tmp = 0.5
	else:
		tmp = 0.8333333333333334
	return tmp
function code(t)
	tmp = 0.0
	if (t <= -0.34)
		tmp = 0.8333333333333334;
	elseif (t <= 1.0)
		tmp = 0.5;
	else
		tmp = 0.8333333333333334;
	end
	return tmp
end
function tmp_2 = code(t)
	tmp = 0.0;
	if (t <= -0.34)
		tmp = 0.8333333333333334;
	elseif (t <= 1.0)
		tmp = 0.5;
	else
		tmp = 0.8333333333333334;
	end
	tmp_2 = tmp;
end
code[t_] := If[LessEqual[t, -0.34], 0.8333333333333334, If[LessEqual[t, 1.0], 0.5, 0.8333333333333334]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.34:\\
\;\;\;\;0.8333333333333334\\

\mathbf{elif}\;t \leq 1:\\
\;\;\;\;0.5\\

\mathbf{else}:\\
\;\;\;\;0.8333333333333334\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -0.340000000000000024 or 1 < t

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac60.2%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out60.2%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*60.2%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval60.2%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac60.3%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified60.3%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around inf 96.5%

      \[\leadsto \color{blue}{0.8333333333333334} \]

    if -0.340000000000000024 < t < 1

    1. Initial program 100.0%

      \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. Step-by-step derivation
      1. times-frac100.0%

        \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      2. sqr-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      3. distribute-rgt-neg-out100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      4. distribute-rgt-neg-out100.0%

        \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      5. swap-sqr100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      6. *-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      7. sqr-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      8. associate-*r*100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      9. metadata-eval100.0%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
      10. times-frac100.0%

        \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
    4. Add Preprocessing
    5. Taylor expanded in t around 0 99.4%

      \[\leadsto \color{blue}{0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -0.34:\\ \;\;\;\;0.8333333333333334\\ \mathbf{elif}\;t \leq 1:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;0.8333333333333334\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 58.4% accurate, 35.0× speedup?

\[\begin{array}{l} \\ 0.5 \end{array} \]
(FPCore (t) :precision binary64 0.5)
double code(double t) {
	return 0.5;
}
real(8) function code(t)
    real(8), intent (in) :: t
    code = 0.5d0
end function
public static double code(double t) {
	return 0.5;
}
def code(t):
	return 0.5
function code(t)
	return 0.5
end
function tmp = code(t)
	tmp = 0.5;
end
code[t_] := 0.5
\begin{array}{l}

\\
0.5
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{1 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
  2. Step-by-step derivation
    1. times-frac79.6%

      \[\leadsto \frac{1 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    2. sqr-neg79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(-2 \cdot t\right) \cdot \left(-2 \cdot t\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    3. distribute-rgt-neg-out79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot \left(-t\right)\right)} \cdot \left(-2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    4. distribute-rgt-neg-out79.6%

      \[\leadsto \frac{1 + \frac{\left(2 \cdot \left(-t\right)\right) \cdot \color{blue}{\left(2 \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    5. swap-sqr79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(2 \cdot 2\right) \cdot \left(\left(-t\right) \cdot \left(-t\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    6. *-commutative79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(\left(-t\right) \cdot \left(-t\right)\right) \cdot \left(2 \cdot 2\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    7. sqr-neg79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(t \cdot t\right)} \cdot \left(2 \cdot 2\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    8. associate-*r*79.6%

      \[\leadsto \frac{1 + \frac{\color{blue}{t \cdot \left(t \cdot \left(2 \cdot 2\right)\right)}}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    9. metadata-eval79.6%

      \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot \color{blue}{4}\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{2 \cdot t}{1 + t} \cdot \frac{2 \cdot t}{1 + t}} \]
    10. times-frac79.7%

      \[\leadsto \frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \color{blue}{\frac{\left(2 \cdot t\right) \cdot \left(2 \cdot t\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
  3. Simplified79.7%

    \[\leadsto \color{blue}{\frac{1 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}{2 + \frac{t \cdot \left(t \cdot 4\right)}{\left(1 + t\right) \cdot \left(1 + t\right)}}} \]
  4. Add Preprocessing
  5. Taylor expanded in t around 0 58.6%

    \[\leadsto \color{blue}{0.5} \]
  6. Final simplification58.6%

    \[\leadsto 0.5 \]
  7. Add Preprocessing

Reproduce

?
herbie shell --seed 2024011 
(FPCore (t)
  :name "Kahan p13 Example 1"
  :precision binary64
  (/ (+ 1.0 (* (/ (* 2.0 t) (+ 1.0 t)) (/ (* 2.0 t) (+ 1.0 t)))) (+ 2.0 (* (/ (* 2.0 t) (+ 1.0 t)) (/ (* 2.0 t) (+ 1.0 t))))))