Bouland and Aaronson, Equation (25)

Percentage Accurate: 73.9% → 98.3%
Time: 6.3s
Alternatives: 6
Speedup: 1.1×

Specification

?
\[\begin{array}{l} \\ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \end{array} \]
(FPCore (a b)
 :precision binary64
 (-
  (+
   (pow (+ (* a a) (* b b)) 2.0)
   (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a))))))
  1.0))
double code(double a, double b) {
	return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (((a * a) * (1.0d0 + a)) + ((b * b) * (1.0d0 - (3.0d0 * a)))))) - 1.0d0
end function
public static double code(double a, double b) {
	return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
def code(a, b):
	return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0
function code(a, b)
	return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(Float64(Float64(a * a) * Float64(1.0 + a)) + Float64(Float64(b * b) * Float64(1.0 - Float64(3.0 * a)))))) - 1.0)
end
function tmp = code(a, b)
	tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(1.0 + a), $MachinePrecision]), $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * N[(1.0 - N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}

\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 6 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 73.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \end{array} \]
(FPCore (a b)
 :precision binary64
 (-
  (+
   (pow (+ (* a a) (* b b)) 2.0)
   (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a))))))
  1.0))
double code(double a, double b) {
	return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (((a * a) * (1.0d0 + a)) + ((b * b) * (1.0d0 - (3.0d0 * a)))))) - 1.0d0
end function
public static double code(double a, double b) {
	return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
}
def code(a, b):
	return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0
function code(a, b)
	return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(Float64(Float64(a * a) * Float64(1.0 + a)) + Float64(Float64(b * b) * Float64(1.0 - Float64(3.0 * a)))))) - 1.0)
end
function tmp = code(a, b)
	tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (1.0 + a)) + ((b * b) * (1.0 - (3.0 * a)))))) - 1.0;
end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(1.0 + a), $MachinePrecision]), $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * N[(1.0 - N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}

\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1
\end{array}

Alternative 1: 98.3% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(a + 1\right) + \left(b \cdot b\right) \cdot \left(1 - a \cdot 3\right)\right)\\ \mathbf{if}\;t\_0 \leq \infty:\\ \;\;\;\;t\_0 + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (let* ((t_0
         (+
          (pow (+ (* a a) (* b b)) 2.0)
          (* 4.0 (+ (* (* a a) (+ a 1.0)) (* (* b b) (- 1.0 (* a 3.0))))))))
   (if (<= t_0 INFINITY) (+ t_0 -1.0) (+ (pow a 4.0) -1.0))))
double code(double a, double b) {
	double t_0 = pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (a + 1.0)) + ((b * b) * (1.0 - (a * 3.0)))));
	double tmp;
	if (t_0 <= ((double) INFINITY)) {
		tmp = t_0 + -1.0;
	} else {
		tmp = pow(a, 4.0) + -1.0;
	}
	return tmp;
}
public static double code(double a, double b) {
	double t_0 = Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (a + 1.0)) + ((b * b) * (1.0 - (a * 3.0)))));
	double tmp;
	if (t_0 <= Double.POSITIVE_INFINITY) {
		tmp = t_0 + -1.0;
	} else {
		tmp = Math.pow(a, 4.0) + -1.0;
	}
	return tmp;
}
def code(a, b):
	t_0 = math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (((a * a) * (a + 1.0)) + ((b * b) * (1.0 - (a * 3.0)))))
	tmp = 0
	if t_0 <= math.inf:
		tmp = t_0 + -1.0
	else:
		tmp = math.pow(a, 4.0) + -1.0
	return tmp
function code(a, b)
	t_0 = Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(Float64(Float64(a * a) * Float64(a + 1.0)) + Float64(Float64(b * b) * Float64(1.0 - Float64(a * 3.0))))))
	tmp = 0.0
	if (t_0 <= Inf)
		tmp = Float64(t_0 + -1.0);
	else
		tmp = Float64((a ^ 4.0) + -1.0);
	end
	return tmp
end
function tmp_2 = code(a, b)
	t_0 = (((a * a) + (b * b)) ^ 2.0) + (4.0 * (((a * a) * (a + 1.0)) + ((b * b) * (1.0 - (a * 3.0)))));
	tmp = 0.0;
	if (t_0 <= Inf)
		tmp = t_0 + -1.0;
	else
		tmp = (a ^ 4.0) + -1.0;
	end
	tmp_2 = tmp;
end
code[a_, b_] := Block[{t$95$0 = N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(N[(N[(a * a), $MachinePrecision] * N[(a + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(b * b), $MachinePrecision] * N[(1.0 - N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, Infinity], N[(t$95$0 + -1.0), $MachinePrecision], N[(N[Power[a, 4.0], $MachinePrecision] + -1.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(a + 1\right) + \left(b \cdot b\right) \cdot \left(1 - a \cdot 3\right)\right)\\
\mathbf{if}\;t\_0 \leq \infty:\\
\;\;\;\;t\_0 + -1\\

\mathbf{else}:\\
\;\;\;\;{a}^{4} + -1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (pow.f64 (+.f64 (*.f64 a a) (*.f64 b b)) #s(literal 2 binary64)) (*.f64 #s(literal 4 binary64) (+.f64 (*.f64 (*.f64 a a) (+.f64 #s(literal 1 binary64) a)) (*.f64 (*.f64 b b) (-.f64 #s(literal 1 binary64) (*.f64 #s(literal 3 binary64) a)))))) < +inf.0

    1. Initial program 99.9%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing

    if +inf.0 < (+.f64 (pow.f64 (+.f64 (*.f64 a a) (*.f64 b b)) #s(literal 2 binary64)) (*.f64 #s(literal 4 binary64) (+.f64 (*.f64 (*.f64 a a) (+.f64 #s(literal 1 binary64) a)) (*.f64 (*.f64 b b) (-.f64 #s(literal 1 binary64) (*.f64 #s(literal 3 binary64) a))))))

    1. Initial program 0.0%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 95.1%

      \[\leadsto \color{blue}{{a}^{4}} - 1 \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;{\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(a + 1\right) + \left(b \cdot b\right) \cdot \left(1 - a \cdot 3\right)\right) \leq \infty:\\ \;\;\;\;\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(a + 1\right) + \left(b \cdot b\right) \cdot \left(1 - a \cdot 3\right)\right)\right) + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 81.1% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.75 \cdot 10^{+17}:\\ \;\;\;\;{a}^{3} \cdot \left(a + 4\right) + -1\\ \mathbf{elif}\;b \leq 6.5 \cdot 10^{+69} \lor \neg \left(b \leq 5.2 \cdot 10^{+75}\right):\\ \;\;\;\;{b}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 1.75e+17)
   (+ (* (pow a 3.0) (+ a 4.0)) -1.0)
   (if (or (<= b 6.5e+69) (not (<= b 5.2e+75)))
     (+ (pow b 4.0) -1.0)
     (+ (pow a 4.0) -1.0))))
double code(double a, double b) {
	double tmp;
	if (b <= 1.75e+17) {
		tmp = (pow(a, 3.0) * (a + 4.0)) + -1.0;
	} else if ((b <= 6.5e+69) || !(b <= 5.2e+75)) {
		tmp = pow(b, 4.0) + -1.0;
	} else {
		tmp = pow(a, 4.0) + -1.0;
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (b <= 1.75d+17) then
        tmp = ((a ** 3.0d0) * (a + 4.0d0)) + (-1.0d0)
    else if ((b <= 6.5d+69) .or. (.not. (b <= 5.2d+75))) then
        tmp = (b ** 4.0d0) + (-1.0d0)
    else
        tmp = (a ** 4.0d0) + (-1.0d0)
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (b <= 1.75e+17) {
		tmp = (Math.pow(a, 3.0) * (a + 4.0)) + -1.0;
	} else if ((b <= 6.5e+69) || !(b <= 5.2e+75)) {
		tmp = Math.pow(b, 4.0) + -1.0;
	} else {
		tmp = Math.pow(a, 4.0) + -1.0;
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 1.75e+17:
		tmp = (math.pow(a, 3.0) * (a + 4.0)) + -1.0
	elif (b <= 6.5e+69) or not (b <= 5.2e+75):
		tmp = math.pow(b, 4.0) + -1.0
	else:
		tmp = math.pow(a, 4.0) + -1.0
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 1.75e+17)
		tmp = Float64(Float64((a ^ 3.0) * Float64(a + 4.0)) + -1.0);
	elseif ((b <= 6.5e+69) || !(b <= 5.2e+75))
		tmp = Float64((b ^ 4.0) + -1.0);
	else
		tmp = Float64((a ^ 4.0) + -1.0);
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 1.75e+17)
		tmp = ((a ^ 3.0) * (a + 4.0)) + -1.0;
	elseif ((b <= 6.5e+69) || ~((b <= 5.2e+75)))
		tmp = (b ^ 4.0) + -1.0;
	else
		tmp = (a ^ 4.0) + -1.0;
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 1.75e+17], N[(N[(N[Power[a, 3.0], $MachinePrecision] * N[(a + 4.0), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], If[Or[LessEqual[b, 6.5e+69], N[Not[LessEqual[b, 5.2e+75]], $MachinePrecision]], N[(N[Power[b, 4.0], $MachinePrecision] + -1.0), $MachinePrecision], N[(N[Power[a, 4.0], $MachinePrecision] + -1.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.75 \cdot 10^{+17}:\\
\;\;\;\;{a}^{3} \cdot \left(a + 4\right) + -1\\

\mathbf{elif}\;b \leq 6.5 \cdot 10^{+69} \lor \neg \left(b \leq 5.2 \cdot 10^{+75}\right):\\
\;\;\;\;{b}^{4} + -1\\

\mathbf{else}:\\
\;\;\;\;{a}^{4} + -1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < 1.75e17

    1. Initial program 79.4%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 80.4%

      \[\leadsto \color{blue}{{a}^{4} \cdot \left(1 + 4 \cdot \frac{1}{a}\right)} - 1 \]
    4. Step-by-step derivation
      1. associate-*r/80.4%

        \[\leadsto {a}^{4} \cdot \left(1 + \color{blue}{\frac{4 \cdot 1}{a}}\right) - 1 \]
      2. metadata-eval80.4%

        \[\leadsto {a}^{4} \cdot \left(1 + \frac{\color{blue}{4}}{a}\right) - 1 \]
    5. Simplified80.4%

      \[\leadsto \color{blue}{{a}^{4} \cdot \left(1 + \frac{4}{a}\right)} - 1 \]
    6. Taylor expanded in a around 0 80.4%

      \[\leadsto \color{blue}{{a}^{3} \cdot \left(4 + a\right)} - 1 \]

    if 1.75e17 < b < 6.5000000000000001e69 or 5.1999999999999997e75 < b

    1. Initial program 72.8%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf 96.1%

      \[\leadsto \color{blue}{{b}^{4}} - 1 \]

    if 6.5000000000000001e69 < b < 5.1999999999999997e75

    1. Initial program 0.0%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 100.0%

      \[\leadsto \color{blue}{{a}^{4}} - 1 \]
  3. Recombined 3 regimes into one program.
  4. Final simplification83.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.75 \cdot 10^{+17}:\\ \;\;\;\;{a}^{3} \cdot \left(a + 4\right) + -1\\ \mathbf{elif}\;b \leq 6.5 \cdot 10^{+69} \lor \neg \left(b \leq 5.2 \cdot 10^{+75}\right):\\ \;\;\;\;{b}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 81.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.22 \cdot 10^{+17}:\\ \;\;\;\;{a}^{4} \cdot \left(1 + \frac{4}{a}\right) + -1\\ \mathbf{elif}\;b \leq 3.1 \cdot 10^{+70} \lor \neg \left(b \leq 4.1 \cdot 10^{+74}\right):\\ \;\;\;\;{b}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 1.22e+17)
   (+ (* (pow a 4.0) (+ 1.0 (/ 4.0 a))) -1.0)
   (if (or (<= b 3.1e+70) (not (<= b 4.1e+74)))
     (+ (pow b 4.0) -1.0)
     (+ (pow a 4.0) -1.0))))
double code(double a, double b) {
	double tmp;
	if (b <= 1.22e+17) {
		tmp = (pow(a, 4.0) * (1.0 + (4.0 / a))) + -1.0;
	} else if ((b <= 3.1e+70) || !(b <= 4.1e+74)) {
		tmp = pow(b, 4.0) + -1.0;
	} else {
		tmp = pow(a, 4.0) + -1.0;
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (b <= 1.22d+17) then
        tmp = ((a ** 4.0d0) * (1.0d0 + (4.0d0 / a))) + (-1.0d0)
    else if ((b <= 3.1d+70) .or. (.not. (b <= 4.1d+74))) then
        tmp = (b ** 4.0d0) + (-1.0d0)
    else
        tmp = (a ** 4.0d0) + (-1.0d0)
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (b <= 1.22e+17) {
		tmp = (Math.pow(a, 4.0) * (1.0 + (4.0 / a))) + -1.0;
	} else if ((b <= 3.1e+70) || !(b <= 4.1e+74)) {
		tmp = Math.pow(b, 4.0) + -1.0;
	} else {
		tmp = Math.pow(a, 4.0) + -1.0;
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 1.22e+17:
		tmp = (math.pow(a, 4.0) * (1.0 + (4.0 / a))) + -1.0
	elif (b <= 3.1e+70) or not (b <= 4.1e+74):
		tmp = math.pow(b, 4.0) + -1.0
	else:
		tmp = math.pow(a, 4.0) + -1.0
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 1.22e+17)
		tmp = Float64(Float64((a ^ 4.0) * Float64(1.0 + Float64(4.0 / a))) + -1.0);
	elseif ((b <= 3.1e+70) || !(b <= 4.1e+74))
		tmp = Float64((b ^ 4.0) + -1.0);
	else
		tmp = Float64((a ^ 4.0) + -1.0);
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 1.22e+17)
		tmp = ((a ^ 4.0) * (1.0 + (4.0 / a))) + -1.0;
	elseif ((b <= 3.1e+70) || ~((b <= 4.1e+74)))
		tmp = (b ^ 4.0) + -1.0;
	else
		tmp = (a ^ 4.0) + -1.0;
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 1.22e+17], N[(N[(N[Power[a, 4.0], $MachinePrecision] * N[(1.0 + N[(4.0 / a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], If[Or[LessEqual[b, 3.1e+70], N[Not[LessEqual[b, 4.1e+74]], $MachinePrecision]], N[(N[Power[b, 4.0], $MachinePrecision] + -1.0), $MachinePrecision], N[(N[Power[a, 4.0], $MachinePrecision] + -1.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.22 \cdot 10^{+17}:\\
\;\;\;\;{a}^{4} \cdot \left(1 + \frac{4}{a}\right) + -1\\

\mathbf{elif}\;b \leq 3.1 \cdot 10^{+70} \lor \neg \left(b \leq 4.1 \cdot 10^{+74}\right):\\
\;\;\;\;{b}^{4} + -1\\

\mathbf{else}:\\
\;\;\;\;{a}^{4} + -1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < 1.22e17

    1. Initial program 79.4%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 80.4%

      \[\leadsto \color{blue}{{a}^{4} \cdot \left(1 + 4 \cdot \frac{1}{a}\right)} - 1 \]
    4. Step-by-step derivation
      1. associate-*r/80.4%

        \[\leadsto {a}^{4} \cdot \left(1 + \color{blue}{\frac{4 \cdot 1}{a}}\right) - 1 \]
      2. metadata-eval80.4%

        \[\leadsto {a}^{4} \cdot \left(1 + \frac{\color{blue}{4}}{a}\right) - 1 \]
    5. Simplified80.4%

      \[\leadsto \color{blue}{{a}^{4} \cdot \left(1 + \frac{4}{a}\right)} - 1 \]

    if 1.22e17 < b < 3.1000000000000003e70 or 4.1e74 < b

    1. Initial program 72.8%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf 96.1%

      \[\leadsto \color{blue}{{b}^{4}} - 1 \]

    if 3.1000000000000003e70 < b < 4.1e74

    1. Initial program 0.0%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 100.0%

      \[\leadsto \color{blue}{{a}^{4}} - 1 \]
  3. Recombined 3 regimes into one program.
  4. Final simplification83.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.22 \cdot 10^{+17}:\\ \;\;\;\;{a}^{4} \cdot \left(1 + \frac{4}{a}\right) + -1\\ \mathbf{elif}\;b \leq 3.1 \cdot 10^{+70} \lor \neg \left(b \leq 4.1 \cdot 10^{+74}\right):\\ \;\;\;\;{b}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{a}^{4} + -1\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 93.9% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -620000000000 \lor \neg \left(a \leq 2.75 \cdot 10^{+22}\right):\\ \;\;\;\;{a}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{b}^{4} + -1\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (or (<= a -620000000000.0) (not (<= a 2.75e+22)))
   (+ (pow a 4.0) -1.0)
   (+ (pow b 4.0) -1.0)))
double code(double a, double b) {
	double tmp;
	if ((a <= -620000000000.0) || !(a <= 2.75e+22)) {
		tmp = pow(a, 4.0) + -1.0;
	} else {
		tmp = pow(b, 4.0) + -1.0;
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if ((a <= (-620000000000.0d0)) .or. (.not. (a <= 2.75d+22))) then
        tmp = (a ** 4.0d0) + (-1.0d0)
    else
        tmp = (b ** 4.0d0) + (-1.0d0)
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if ((a <= -620000000000.0) || !(a <= 2.75e+22)) {
		tmp = Math.pow(a, 4.0) + -1.0;
	} else {
		tmp = Math.pow(b, 4.0) + -1.0;
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if (a <= -620000000000.0) or not (a <= 2.75e+22):
		tmp = math.pow(a, 4.0) + -1.0
	else:
		tmp = math.pow(b, 4.0) + -1.0
	return tmp
function code(a, b)
	tmp = 0.0
	if ((a <= -620000000000.0) || !(a <= 2.75e+22))
		tmp = Float64((a ^ 4.0) + -1.0);
	else
		tmp = Float64((b ^ 4.0) + -1.0);
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if ((a <= -620000000000.0) || ~((a <= 2.75e+22)))
		tmp = (a ^ 4.0) + -1.0;
	else
		tmp = (b ^ 4.0) + -1.0;
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[Or[LessEqual[a, -620000000000.0], N[Not[LessEqual[a, 2.75e+22]], $MachinePrecision]], N[(N[Power[a, 4.0], $MachinePrecision] + -1.0), $MachinePrecision], N[(N[Power[b, 4.0], $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -620000000000 \lor \neg \left(a \leq 2.75 \cdot 10^{+22}\right):\\
\;\;\;\;{a}^{4} + -1\\

\mathbf{else}:\\
\;\;\;\;{b}^{4} + -1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -6.2e11 or 2.7500000000000001e22 < a

    1. Initial program 50.8%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf 92.6%

      \[\leadsto \color{blue}{{a}^{4}} - 1 \]

    if -6.2e11 < a < 2.7500000000000001e22

    1. Initial program 99.2%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf 95.2%

      \[\leadsto \color{blue}{{b}^{4}} - 1 \]
  3. Recombined 2 regimes into one program.
  4. Final simplification94.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -620000000000 \lor \neg \left(a \leq 2.75 \cdot 10^{+22}\right):\\ \;\;\;\;{a}^{4} + -1\\ \mathbf{else}:\\ \;\;\;\;{b}^{4} + -1\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 68.9% accurate, 1.3× speedup?

\[\begin{array}{l} \\ {a}^{4} + -1 \end{array} \]
(FPCore (a b) :precision binary64 (+ (pow a 4.0) -1.0))
double code(double a, double b) {
	return pow(a, 4.0) + -1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = (a ** 4.0d0) + (-1.0d0)
end function
public static double code(double a, double b) {
	return Math.pow(a, 4.0) + -1.0;
}
def code(a, b):
	return math.pow(a, 4.0) + -1.0
function code(a, b)
	return Float64((a ^ 4.0) + -1.0)
end
function tmp = code(a, b)
	tmp = (a ^ 4.0) + -1.0;
end
code[a_, b_] := N[(N[Power[a, 4.0], $MachinePrecision] + -1.0), $MachinePrecision]
\begin{array}{l}

\\
{a}^{4} + -1
\end{array}
Derivation
  1. Initial program 77.3%

    \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
  2. Add Preprocessing
  3. Taylor expanded in a around inf 71.1%

    \[\leadsto \color{blue}{{a}^{4}} - 1 \]
  4. Final simplification71.1%

    \[\leadsto {a}^{4} + -1 \]
  5. Add Preprocessing

Alternative 6: 24.9% accurate, 130.0× speedup?

\[\begin{array}{l} \\ -1 \end{array} \]
(FPCore (a b) :precision binary64 -1.0)
double code(double a, double b) {
	return -1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = -1.0d0
end function
public static double code(double a, double b) {
	return -1.0;
}
def code(a, b):
	return -1.0
function code(a, b)
	return -1.0
end
function tmp = code(a, b)
	tmp = -1.0;
end
code[a_, b_] := -1.0
\begin{array}{l}

\\
-1
\end{array}
Derivation
  1. Initial program 77.3%

    \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(\left(a \cdot a\right) \cdot \left(1 + a\right) + \left(b \cdot b\right) \cdot \left(1 - 3 \cdot a\right)\right)\right) - 1 \]
  2. Add Preprocessing
  3. Taylor expanded in b around inf 67.1%

    \[\leadsto \color{blue}{{b}^{4}} - 1 \]
  4. Taylor expanded in b around 0 28.6%

    \[\leadsto \color{blue}{-1} \]
  5. Final simplification28.6%

    \[\leadsto -1 \]
  6. Add Preprocessing

Reproduce

?
herbie shell --seed 2024066 
(FPCore (a b)
  :name "Bouland and Aaronson, Equation (25)"
  :precision binary64
  (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (+ (* (* a a) (+ 1.0 a)) (* (* b b) (- 1.0 (* 3.0 a)))))) 1.0))