Octave 3.8, oct_fill_randg

Percentage Accurate: 99.8% → 99.8%

Time: 7.8s

Alternatives: 8

Speedup: 2.4×

Specification

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := a - \frac{1}{3}\\ t\_0 \cdot \left(1 + \frac{1}{\sqrt{9 \cdot t\_0}} \cdot rand\right) \end{array} \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (let* ((t_0 (- a (/ 1.0 3.0))))
   (* t_0 (+ 1.0 (* (/ 1.0 (sqrt (* 9.0 t_0))) rand)))))

C

double code(double a, double rand) {
	double t_0 = a - (1.0 / 3.0);
	return t_0 * (1.0 + ((1.0 / sqrt((9.0 * t_0))) * rand));
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    real(8) :: t_0
    t_0 = a - (1.0d0 / 3.0d0)
    code = t_0 * (1.0d0 + ((1.0d0 / sqrt((9.0d0 * t_0))) * rand))
end function

Java

public static double code(double a, double rand) {
	double t_0 = a - (1.0 / 3.0);
	return t_0 * (1.0 + ((1.0 / Math.sqrt((9.0 * t_0))) * rand));
}

Python

def code(a, rand):
	t_0 = a - (1.0 / 3.0)
	return t_0 * (1.0 + ((1.0 / math.sqrt((9.0 * t_0))) * rand))

Julia

function code(a, rand)
	t_0 = Float64(a - Float64(1.0 / 3.0))
	return Float64(t_0 * Float64(1.0 + Float64(Float64(1.0 / sqrt(Float64(9.0 * t_0))) * rand)))
end

MATLAB

function tmp = code(a, rand)
	t_0 = a - (1.0 / 3.0);
	tmp = t_0 * (1.0 + ((1.0 / sqrt((9.0 * t_0))) * rand));
end

Wolfram

code[a_, rand_] := Block[{t$95$0 = N[(a - N[(1.0 / 3.0), $MachinePrecision]), $MachinePrecision]}, N[(t$95$0 * N[(1.0 + N[(N[(1.0 / N[Sqrt[N[(9.0 * t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * rand), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]

Initial Program: 99.8% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := a - \frac{1}{3}\\ t\_0 \cdot \left(1 + \frac{1}{\sqrt{9 \cdot t\_0}} \cdot rand\right) \end{array} \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (let* ((t_0 (- a (/ 1.0 3.0))))
   (* t_0 (+ 1.0 (* (/ 1.0 (sqrt (* 9.0 t_0))) rand)))))

C

double code(double a, double rand) {
	double t_0 = a - (1.0 / 3.0);
	return t_0 * (1.0 + ((1.0 / sqrt((9.0 * t_0))) * rand));
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    real(8) :: t_0
    t_0 = a - (1.0d0 / 3.0d0)
    code = t_0 * (1.0d0 + ((1.0d0 / sqrt((9.0d0 * t_0))) * rand))
end function

Java

public static double code(double a, double rand) {
	double t_0 = a - (1.0 / 3.0);
	return t_0 * (1.0 + ((1.0 / Math.sqrt((9.0 * t_0))) * rand));
}

Python

def code(a, rand):
	t_0 = a - (1.0 / 3.0)
	return t_0 * (1.0 + ((1.0 / math.sqrt((9.0 * t_0))) * rand))

Julia

function code(a, rand)
	t_0 = Float64(a - Float64(1.0 / 3.0))
	return Float64(t_0 * Float64(1.0 + Float64(Float64(1.0 / sqrt(Float64(9.0 * t_0))) * rand)))
end

MATLAB

function tmp = code(a, rand)
	t_0 = a - (1.0 / 3.0);
	tmp = t_0 * (1.0 + ((1.0 / sqrt((9.0 * t_0))) * rand));
end

Wolfram

code[a_, rand_] := Block[{t$95$0 = N[(a - N[(1.0 / 3.0), $MachinePrecision]), $MachinePrecision]}, N[(t$95$0 * N[(1.0 + N[(N[(1.0 / N[Sqrt[N[(9.0 * t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * rand), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]

Alternative 1: 99.8% accurate, 1.6× speedup

Math

\[\begin{array}{l} \\ \mathsf{fma}\left(\frac{0.3333333333333333 \cdot \left(a - 0.3333333333333333\right)}{\sqrt{a - 0.3333333333333333}}, rand, a - 0.3333333333333333\right) \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (fma
  (/
   (* 0.3333333333333333 (- a 0.3333333333333333))
   (sqrt (- a 0.3333333333333333)))
  rand
  (- a 0.3333333333333333)))

C

double code(double a, double rand) {
	return fma(((0.3333333333333333 * (a - 0.3333333333333333)) / sqrt((a - 0.3333333333333333))), rand, (a - 0.3333333333333333));
}

Julia

function code(a, rand)
	return fma(Float64(Float64(0.3333333333333333 * Float64(a - 0.3333333333333333)) / sqrt(Float64(a - 0.3333333333333333))), rand, Float64(a - 0.3333333333333333))
end

Wolfram

code[a_, rand_] := N[(N[(N[(0.3333333333333333 * N[(a - 0.3333333333333333), $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(a - 0.3333333333333333), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * rand + N[(a - 0.3333333333333333), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 99.8%

   \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
2. Add Preprocessing
3. Step-by-step derivation

   1. lift-*.f64 N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   2. lift-+.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   3. +-commutative N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand + 1\right)} \]

   4. distribute-lft-in N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) + \left(a - \frac{1}{3}\right) \cdot 1} \]

   5. lift-*.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   6. associate-*r* N/A

      \[\leadsto \color{blue}{\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   7. *-rgt-identity N/A

      \[\leadsto \left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand + \color{blue}{\left(a - \frac{1}{3}\right)} \]

   8. lower-fma.f64 N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}, rand, a - \frac{1}{3}\right)} \]

4. Applied rewrites 99.8%

   \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.3333333333333333 \cdot \left(a - 0.3333333333333333\right)}{\sqrt{a - 0.3333333333333333}}, rand, a - 0.3333333333333333\right)} \]
5. Add Preprocessing

Alternative 2: 91.8% accurate, 2.1× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;rand \leq -2.9 \cdot 10^{+102} \lor \neg \left(rand \leq 1.95 \cdot 10^{+66}\right):\\ \;\;\;\;\left(\sqrt{a} \cdot 0.3333333333333333\right) \cdot rand\\ \mathbf{else}:\\ \;\;\;\;a - 0.3333333333333333\\ \end{array} \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (if (or (<= rand -2.9e+102) (not (<= rand 1.95e+66)))
   (* (* (sqrt a) 0.3333333333333333) rand)
   (- a 0.3333333333333333)))

C

double code(double a, double rand) {
	double tmp;
	if ((rand <= -2.9e+102) || !(rand <= 1.95e+66)) {
		tmp = (sqrt(a) * 0.3333333333333333) * rand;
	} else {
		tmp = a - 0.3333333333333333;
	}
	return tmp;
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    real(8) :: tmp
    if ((rand <= (-2.9d+102)) .or. (.not. (rand <= 1.95d+66))) then
        tmp = (sqrt(a) * 0.3333333333333333d0) * rand
    else
        tmp = a - 0.3333333333333333d0
    end if
    code = tmp
end function

Java

public static double code(double a, double rand) {
	double tmp;
	if ((rand <= -2.9e+102) || !(rand <= 1.95e+66)) {
		tmp = (Math.sqrt(a) * 0.3333333333333333) * rand;
	} else {
		tmp = a - 0.3333333333333333;
	}
	return tmp;
}

Python

def code(a, rand):
	tmp = 0
	if (rand <= -2.9e+102) or not (rand <= 1.95e+66):
		tmp = (math.sqrt(a) * 0.3333333333333333) * rand
	else:
		tmp = a - 0.3333333333333333
	return tmp

Julia

function code(a, rand)
	tmp = 0.0
	if ((rand <= -2.9e+102) || !(rand <= 1.95e+66))
		tmp = Float64(Float64(sqrt(a) * 0.3333333333333333) * rand);
	else
		tmp = Float64(a - 0.3333333333333333);
	end
	return tmp
end

MATLAB

function tmp_2 = code(a, rand)
	tmp = 0.0;
	if ((rand <= -2.9e+102) || ~((rand <= 1.95e+66)))
		tmp = (sqrt(a) * 0.3333333333333333) * rand;
	else
		tmp = a - 0.3333333333333333;
	end
	tmp_2 = tmp;
end

Wolfram

code[a_, rand_] := If[Or[LessEqual[rand, -2.9e+102], N[Not[LessEqual[rand, 1.95e+66]], $MachinePrecision]], N[(N[(N[Sqrt[a], $MachinePrecision] * 0.3333333333333333), $MachinePrecision] * rand), $MachinePrecision], N[(a - 0.3333333333333333), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if rand < -2.9000000000000002e102 or 1.9500000000000002e66 < rand

   1. Initial program 99.6%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing

   3. Taylor expanded in rand around inf

      \[\leadsto \color{blue}{rand \cdot \left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right)} \]
   4. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \color{blue}{\left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right) \cdot rand} \]

      2. lower-*.f64 N/A

         \[\leadsto \color{blue}{\left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right) \cdot rand} \]

      3. associate--l+ N/A

         \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \left(\frac{a}{rand} - \frac{1}{3} \cdot \frac{1}{rand}\right)\right)} \cdot rand \]

      4. *-commutative N/A

         \[\leadsto \left(\color{blue}{\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3}} + \left(\frac{a}{rand} - \frac{1}{3} \cdot \frac{1}{rand}\right)\right) \cdot rand \]

      5. associate-*r/ N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \left(\frac{a}{rand} - \color{blue}{\frac{\frac{1}{3} \cdot 1}{rand}}\right)\right) \cdot rand \]

      6. metadata-eval N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \left(\frac{a}{rand} - \frac{\color{blue}{\frac{1}{3}}}{rand}\right)\right) \cdot rand \]

      7. div-sub N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \color{blue}{\frac{a - \frac{1}{3}}{rand}}\right) \cdot rand \]

      8. lower-fma.f64 N/A

         \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{a - \frac{1}{3}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right)} \cdot rand \]

      9. lower-sqrt.f64 N/A

         \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a - \frac{1}{3}}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right) \cdot rand \]

      10. lower--.f64 N/A

          \[\leadsto \mathsf{fma}\left(\sqrt{\color{blue}{a - \frac{1}{3}}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right) \cdot rand \]

      11. lower-/.f64 N/A

          \[\leadsto \mathsf{fma}\left(\sqrt{a - \frac{1}{3}}, \frac{1}{3}, \color{blue}{\frac{a - \frac{1}{3}}{rand}}\right) \cdot rand \]

      12. lower--.f64 99.5

          \[\leadsto \mathsf{fma}\left(\sqrt{a - 0.3333333333333333}, 0.3333333333333333, \frac{\color{blue}{a - 0.3333333333333333}}{rand}\right) \cdot rand \]

   5. Applied rewrites 99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{a - 0.3333333333333333}, 0.3333333333333333, \frac{a - 0.3333333333333333}{rand}\right) \cdot rand} \]

   6. Taylor expanded in rand around inf

      \[\leadsto \left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}}\right) \cdot rand \]
   7. Step-by-step derivation

   8. Applied rewrites 95.6%

      \[\leadsto \left(\sqrt{a - 0.3333333333333333} \cdot 0.3333333333333333\right) \cdot rand \]

   9. Taylor expanded in a around -inf

      \[\leadsto \left(\frac{-1}{3} \cdot \left(\sqrt{a} \cdot {\left(\sqrt{-1}\right)}^{2}\right)\right) \cdot rand \]
   10. Step-by-step derivation

   11. Applied rewrites 95.3%

       \[\leadsto \left(\sqrt{a} \cdot 0.3333333333333333\right) \cdot rand \]

   if -2.9000000000000002e102 < rand < 1.9500000000000002e66

   1. Initial program 99.9%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      2. lift--.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right)} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      3. flip-- N/A

         \[\leadsto \color{blue}{\frac{a \cdot a - \frac{1}{3} \cdot \frac{1}{3}}{a + \frac{1}{3}}} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      4. associate-*l/ N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

      5. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

   4. Applied rewrites 50.2%

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - 0.1111111111111111\right) \cdot \mathsf{fma}\left(\frac{rand}{\sqrt{a - 0.3333333333333333}}, 0.3333333333333333, 1\right)}{a + 0.3333333333333333}} \]

   5. Taylor expanded in rand around 0

      \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]
   6. Step-by-step derivation

      1. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]

      2. lower--.f64 N/A

         \[\leadsto \frac{\color{blue}{{a}^{2} - \frac{1}{9}}}{\frac{1}{3} + a} \]

      3. unpow2 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      4. lower-*.f64 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      5. lower-+.f64 45.0

         \[\leadsto \frac{a \cdot a - 0.1111111111111111}{\color{blue}{0.3333333333333333 + a}} \]

   7. Applied rewrites 45.0%

      \[\leadsto \color{blue}{\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333 + a}} \]
   8. Step-by-step derivation

   9. Applied rewrites 93.7%

      \[\leadsto \color{blue}{a - 0.3333333333333333} \]
3. Recombined 2 regimes into one program.

4. Final simplification 94.3%

   \[\leadsto \begin{array}{l} \mathbf{if}\;rand \leq -2.9 \cdot 10^{+102} \lor \neg \left(rand \leq 1.95 \cdot 10^{+66}\right):\\ \;\;\;\;\left(\sqrt{a} \cdot 0.3333333333333333\right) \cdot rand\\ \mathbf{else}:\\ \;\;\;\;a - 0.3333333333333333\\ \end{array} \]
5. Add Preprocessing

Alternative 3: 91.8% accurate, 2.1× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;rand \leq -2.5 \cdot 10^{+102}:\\ \;\;\;\;\left(rand \cdot 0.3333333333333333\right) \cdot \sqrt{a}\\ \mathbf{elif}\;rand \leq 1.95 \cdot 10^{+66}:\\ \;\;\;\;a - 0.3333333333333333\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{a} \cdot 0.3333333333333333\right) \cdot rand\\ \end{array} \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (if (<= rand -2.5e+102)
   (* (* rand 0.3333333333333333) (sqrt a))
   (if (<= rand 1.95e+66)
     (- a 0.3333333333333333)
     (* (* (sqrt a) 0.3333333333333333) rand))))

C

double code(double a, double rand) {
	double tmp;
	if (rand <= -2.5e+102) {
		tmp = (rand * 0.3333333333333333) * sqrt(a);
	} else if (rand <= 1.95e+66) {
		tmp = a - 0.3333333333333333;
	} else {
		tmp = (sqrt(a) * 0.3333333333333333) * rand;
	}
	return tmp;
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    real(8) :: tmp
    if (rand <= (-2.5d+102)) then
        tmp = (rand * 0.3333333333333333d0) * sqrt(a)
    else if (rand <= 1.95d+66) then
        tmp = a - 0.3333333333333333d0
    else
        tmp = (sqrt(a) * 0.3333333333333333d0) * rand
    end if
    code = tmp
end function

Java

public static double code(double a, double rand) {
	double tmp;
	if (rand <= -2.5e+102) {
		tmp = (rand * 0.3333333333333333) * Math.sqrt(a);
	} else if (rand <= 1.95e+66) {
		tmp = a - 0.3333333333333333;
	} else {
		tmp = (Math.sqrt(a) * 0.3333333333333333) * rand;
	}
	return tmp;
}

Python

def code(a, rand):
	tmp = 0
	if rand <= -2.5e+102:
		tmp = (rand * 0.3333333333333333) * math.sqrt(a)
	elif rand <= 1.95e+66:
		tmp = a - 0.3333333333333333
	else:
		tmp = (math.sqrt(a) * 0.3333333333333333) * rand
	return tmp

Julia

function code(a, rand)
	tmp = 0.0
	if (rand <= -2.5e+102)
		tmp = Float64(Float64(rand * 0.3333333333333333) * sqrt(a));
	elseif (rand <= 1.95e+66)
		tmp = Float64(a - 0.3333333333333333);
	else
		tmp = Float64(Float64(sqrt(a) * 0.3333333333333333) * rand);
	end
	return tmp
end

MATLAB

function tmp_2 = code(a, rand)
	tmp = 0.0;
	if (rand <= -2.5e+102)
		tmp = (rand * 0.3333333333333333) * sqrt(a);
	elseif (rand <= 1.95e+66)
		tmp = a - 0.3333333333333333;
	else
		tmp = (sqrt(a) * 0.3333333333333333) * rand;
	end
	tmp_2 = tmp;
end

Wolfram

code[a_, rand_] := If[LessEqual[rand, -2.5e+102], N[(N[(rand * 0.3333333333333333), $MachinePrecision] * N[Sqrt[a], $MachinePrecision]), $MachinePrecision], If[LessEqual[rand, 1.95e+66], N[(a - 0.3333333333333333), $MachinePrecision], N[(N[(N[Sqrt[a], $MachinePrecision] * 0.3333333333333333), $MachinePrecision] * rand), $MachinePrecision]]]

Derivation

1. Split input into 3 regimes

2. if rand < -2.5e102

   1. Initial program 99.6%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      2. lift-+.f64 N/A

         \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      3. +-commutative N/A

         \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand + 1\right)} \]

      4. distribute-lft-in N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) + \left(a - \frac{1}{3}\right) \cdot 1} \]

      5. lift-*.f64 N/A

         \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} + \left(a - \frac{1}{3}\right) \cdot 1 \]

      6. associate-*r* N/A

         \[\leadsto \color{blue}{\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand} + \left(a - \frac{1}{3}\right) \cdot 1 \]

      7. *-rgt-identity N/A

         \[\leadsto \left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand + \color{blue}{\left(a - \frac{1}{3}\right)} \]

      8. lower-fma.f64 N/A

         \[\leadsto \color{blue}{\mathsf{fma}\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}, rand, a - \frac{1}{3}\right)} \]

   4. Applied rewrites 99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.3333333333333333 \cdot \left(a - 0.3333333333333333\right)}{\sqrt{a - 0.3333333333333333}}, rand, a - 0.3333333333333333\right)} \]

   5. Taylor expanded in a around inf

      \[\leadsto \color{blue}{a \cdot \left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right)} \]
   6. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \color{blue}{\left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right) \cdot a} \]

      2. lower-*.f64 N/A

         \[\leadsto \color{blue}{\left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right) \cdot a} \]

      3. +-commutative N/A

         \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right) + 1\right)} \cdot a \]

      4. *-commutative N/A

         \[\leadsto \left(\frac{1}{3} \cdot \color{blue}{\left(rand \cdot \sqrt{\frac{1}{a}}\right)} + 1\right) \cdot a \]

      5. associate-*r* N/A

         \[\leadsto \left(\color{blue}{\left(\frac{1}{3} \cdot rand\right) \cdot \sqrt{\frac{1}{a}}} + 1\right) \cdot a \]

      6. lower-fma.f64 N/A

         \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{3} \cdot rand, \sqrt{\frac{1}{a}}, 1\right)} \cdot a \]

      7. lower-*.f64 N/A

         \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{3} \cdot rand}, \sqrt{\frac{1}{a}}, 1\right) \cdot a \]

      8. lower-sqrt.f64 N/A

         \[\leadsto \mathsf{fma}\left(\frac{1}{3} \cdot rand, \color{blue}{\sqrt{\frac{1}{a}}}, 1\right) \cdot a \]

      9. lower-/.f64 99.5

         \[\leadsto \mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{\color{blue}{\frac{1}{a}}}, 1\right) \cdot a \]

   7. Applied rewrites 99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{\frac{1}{a}}, 1\right) \cdot a} \]

   8. Taylor expanded in a around 0

      \[\leadsto \frac{1}{3} \cdot \color{blue}{\left(\sqrt{a} \cdot rand\right)} \]
   9. Step-by-step derivation

   10. Applied rewrites 96.7%

       \[\leadsto \left(\sqrt{a} \cdot rand\right) \cdot \color{blue}{0.3333333333333333} \]
   11. Step-by-step derivation

   12. Applied rewrites 96.8%

       \[\leadsto \left(rand \cdot 0.3333333333333333\right) \cdot \sqrt{a} \]

   if -2.5e102 < rand < 1.9500000000000002e66

   1. Initial program 99.9%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      2. lift--.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right)} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      3. flip-- N/A

         \[\leadsto \color{blue}{\frac{a \cdot a - \frac{1}{3} \cdot \frac{1}{3}}{a + \frac{1}{3}}} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      4. associate-*l/ N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

      5. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

   4. Applied rewrites 50.2%

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - 0.1111111111111111\right) \cdot \mathsf{fma}\left(\frac{rand}{\sqrt{a - 0.3333333333333333}}, 0.3333333333333333, 1\right)}{a + 0.3333333333333333}} \]

   5. Taylor expanded in rand around 0

      \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]
   6. Step-by-step derivation

      1. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]

      2. lower--.f64 N/A

         \[\leadsto \frac{\color{blue}{{a}^{2} - \frac{1}{9}}}{\frac{1}{3} + a} \]

      3. unpow2 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      4. lower-*.f64 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      5. lower-+.f64 45.0

         \[\leadsto \frac{a \cdot a - 0.1111111111111111}{\color{blue}{0.3333333333333333 + a}} \]

   7. Applied rewrites 45.0%

      \[\leadsto \color{blue}{\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333 + a}} \]
   8. Step-by-step derivation

   9. Applied rewrites 93.7%

      \[\leadsto \color{blue}{a - 0.3333333333333333} \]

   if 1.9500000000000002e66 < rand

   1. Initial program 99.6%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing

   3. Taylor expanded in rand around inf

      \[\leadsto \color{blue}{rand \cdot \left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right)} \]
   4. Step-by-step derivation

      1. *-commutative N/A

         \[\leadsto \color{blue}{\left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right) \cdot rand} \]

      2. lower-*.f64 N/A

         \[\leadsto \color{blue}{\left(\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \frac{a}{rand}\right) - \frac{1}{3} \cdot \frac{1}{rand}\right) \cdot rand} \]

      3. associate--l+ N/A

         \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}} + \left(\frac{a}{rand} - \frac{1}{3} \cdot \frac{1}{rand}\right)\right)} \cdot rand \]

      4. *-commutative N/A

         \[\leadsto \left(\color{blue}{\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3}} + \left(\frac{a}{rand} - \frac{1}{3} \cdot \frac{1}{rand}\right)\right) \cdot rand \]

      5. associate-*r/ N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \left(\frac{a}{rand} - \color{blue}{\frac{\frac{1}{3} \cdot 1}{rand}}\right)\right) \cdot rand \]

      6. metadata-eval N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \left(\frac{a}{rand} - \frac{\color{blue}{\frac{1}{3}}}{rand}\right)\right) \cdot rand \]

      7. div-sub N/A

         \[\leadsto \left(\sqrt{a - \frac{1}{3}} \cdot \frac{1}{3} + \color{blue}{\frac{a - \frac{1}{3}}{rand}}\right) \cdot rand \]

      8. lower-fma.f64 N/A

         \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{a - \frac{1}{3}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right)} \cdot rand \]

      9. lower-sqrt.f64 N/A

         \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a - \frac{1}{3}}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right) \cdot rand \]

      10. lower--.f64 N/A

          \[\leadsto \mathsf{fma}\left(\sqrt{\color{blue}{a - \frac{1}{3}}}, \frac{1}{3}, \frac{a - \frac{1}{3}}{rand}\right) \cdot rand \]

      11. lower-/.f64 N/A

          \[\leadsto \mathsf{fma}\left(\sqrt{a - \frac{1}{3}}, \frac{1}{3}, \color{blue}{\frac{a - \frac{1}{3}}{rand}}\right) \cdot rand \]

      12. lower--.f64 99.5

          \[\leadsto \mathsf{fma}\left(\sqrt{a - 0.3333333333333333}, 0.3333333333333333, \frac{\color{blue}{a - 0.3333333333333333}}{rand}\right) \cdot rand \]

   5. Applied rewrites 99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{a - 0.3333333333333333}, 0.3333333333333333, \frac{a - 0.3333333333333333}{rand}\right) \cdot rand} \]

   6. Taylor expanded in rand around inf

      \[\leadsto \left(\frac{1}{3} \cdot \sqrt{a - \frac{1}{3}}\right) \cdot rand \]
   7. Step-by-step derivation

   8. Applied rewrites 94.9%

      \[\leadsto \left(\sqrt{a - 0.3333333333333333} \cdot 0.3333333333333333\right) \cdot rand \]

   9. Taylor expanded in a around -inf

      \[\leadsto \left(\frac{-1}{3} \cdot \left(\sqrt{a} \cdot {\left(\sqrt{-1}\right)}^{2}\right)\right) \cdot rand \]
   10. Step-by-step derivation

   11. Applied rewrites 94.3%

       \[\leadsto \left(\sqrt{a} \cdot 0.3333333333333333\right) \cdot rand \]
3. Recombined 3 regimes into one program.
4. Add Preprocessing

Alternative 4: 99.8% accurate, 2.4× speedup

Math

\[\begin{array}{l} \\ \mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{a - 0.3333333333333333}, a - 0.3333333333333333\right) \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (fma
  (* 0.3333333333333333 rand)
  (sqrt (- a 0.3333333333333333))
  (- a 0.3333333333333333)))

C

double code(double a, double rand) {
	return fma((0.3333333333333333 * rand), sqrt((a - 0.3333333333333333)), (a - 0.3333333333333333));
}

Julia

function code(a, rand)
	return fma(Float64(0.3333333333333333 * rand), sqrt(Float64(a - 0.3333333333333333)), Float64(a - 0.3333333333333333))
end

Wolfram

code[a_, rand_] := N[(N[(0.3333333333333333 * rand), $MachinePrecision] * N[Sqrt[N[(a - 0.3333333333333333), $MachinePrecision]], $MachinePrecision] + N[(a - 0.3333333333333333), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 99.8%

   \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
2. Add Preprocessing

3. Taylor expanded in rand around 0

   \[\leadsto \color{blue}{\left(a + \frac{1}{3} \cdot \left(rand \cdot \sqrt{a - \frac{1}{3}}\right)\right) - \frac{1}{3}} \]
4. Step-by-step derivation

   1. +-commutative N/A

      \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot \left(rand \cdot \sqrt{a - \frac{1}{3}}\right) + a\right)} - \frac{1}{3} \]

   2. associate--l+ N/A

      \[\leadsto \color{blue}{\frac{1}{3} \cdot \left(rand \cdot \sqrt{a - \frac{1}{3}}\right) + \left(a - \frac{1}{3}\right)} \]

   3. associate-*r* N/A

      \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot rand\right) \cdot \sqrt{a - \frac{1}{3}}} + \left(a - \frac{1}{3}\right) \]

   4. lower-fma.f64 N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{3} \cdot rand, \sqrt{a - \frac{1}{3}}, a - \frac{1}{3}\right)} \]

   5. lower-*.f64 N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{3} \cdot rand}, \sqrt{a - \frac{1}{3}}, a - \frac{1}{3}\right) \]

   6. lower-sqrt.f64 N/A

      \[\leadsto \mathsf{fma}\left(\frac{1}{3} \cdot rand, \color{blue}{\sqrt{a - \frac{1}{3}}}, a - \frac{1}{3}\right) \]

   7. lower--.f64 N/A

      \[\leadsto \mathsf{fma}\left(\frac{1}{3} \cdot rand, \sqrt{\color{blue}{a - \frac{1}{3}}}, a - \frac{1}{3}\right) \]

   8. lower--.f64 99.8

      \[\leadsto \mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{a - 0.3333333333333333}, \color{blue}{a - 0.3333333333333333}\right) \]

5. Applied rewrites 99.8%

   \[\leadsto \color{blue}{\mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{a - 0.3333333333333333}, a - 0.3333333333333333\right)} \]
6. Add Preprocessing

Alternative 5: 67.1% accurate, 2.6× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;rand \leq 1.45 \cdot 10^{+118}:\\ \;\;\;\;a - 0.3333333333333333\\ \mathbf{else}:\\ \;\;\;\;\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333}\\ \end{array} \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (if (<= rand 1.45e+118)
   (- a 0.3333333333333333)
   (/ (- (* a a) 0.1111111111111111) 0.3333333333333333)))

C

double code(double a, double rand) {
	double tmp;
	if (rand <= 1.45e+118) {
		tmp = a - 0.3333333333333333;
	} else {
		tmp = ((a * a) - 0.1111111111111111) / 0.3333333333333333;
	}
	return tmp;
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    real(8) :: tmp
    if (rand <= 1.45d+118) then
        tmp = a - 0.3333333333333333d0
    else
        tmp = ((a * a) - 0.1111111111111111d0) / 0.3333333333333333d0
    end if
    code = tmp
end function

Java

public static double code(double a, double rand) {
	double tmp;
	if (rand <= 1.45e+118) {
		tmp = a - 0.3333333333333333;
	} else {
		tmp = ((a * a) - 0.1111111111111111) / 0.3333333333333333;
	}
	return tmp;
}

Python

def code(a, rand):
	tmp = 0
	if rand <= 1.45e+118:
		tmp = a - 0.3333333333333333
	else:
		tmp = ((a * a) - 0.1111111111111111) / 0.3333333333333333
	return tmp

Julia

function code(a, rand)
	tmp = 0.0
	if (rand <= 1.45e+118)
		tmp = Float64(a - 0.3333333333333333);
	else
		tmp = Float64(Float64(Float64(a * a) - 0.1111111111111111) / 0.3333333333333333);
	end
	return tmp
end

MATLAB

function tmp_2 = code(a, rand)
	tmp = 0.0;
	if (rand <= 1.45e+118)
		tmp = a - 0.3333333333333333;
	else
		tmp = ((a * a) - 0.1111111111111111) / 0.3333333333333333;
	end
	tmp_2 = tmp;
end

Wolfram

code[a_, rand_] := If[LessEqual[rand, 1.45e+118], N[(a - 0.3333333333333333), $MachinePrecision], N[(N[(N[(a * a), $MachinePrecision] - 0.1111111111111111), $MachinePrecision] / 0.3333333333333333), $MachinePrecision]]

Derivation

1. Split input into 2 regimes

2. if rand < 1.45000000000000008e118

   1. Initial program 99.9%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      2. lift--.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right)} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      3. flip-- N/A

         \[\leadsto \color{blue}{\frac{a \cdot a - \frac{1}{3} \cdot \frac{1}{3}}{a + \frac{1}{3}}} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      4. associate-*l/ N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

      5. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

   4. Applied rewrites 52.3%

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - 0.1111111111111111\right) \cdot \mathsf{fma}\left(\frac{rand}{\sqrt{a - 0.3333333333333333}}, 0.3333333333333333, 1\right)}{a + 0.3333333333333333}} \]

   5. Taylor expanded in rand around 0

      \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]
   6. Step-by-step derivation

      1. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]

      2. lower--.f64 N/A

         \[\leadsto \frac{\color{blue}{{a}^{2} - \frac{1}{9}}}{\frac{1}{3} + a} \]

      3. unpow2 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      4. lower-*.f64 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      5. lower-+.f64 36.2

         \[\leadsto \frac{a \cdot a - 0.1111111111111111}{\color{blue}{0.3333333333333333 + a}} \]

   7. Applied rewrites 36.2%

      \[\leadsto \color{blue}{\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333 + a}} \]
   8. Step-by-step derivation

   9. Applied rewrites 76.4%

      \[\leadsto \color{blue}{a - 0.3333333333333333} \]

   if 1.45000000000000008e118 < rand

   1. Initial program 99.6%

      \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
   2. Add Preprocessing
   3. Step-by-step derivation

      1. lift-*.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

      2. lift--.f64 N/A

         \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right)} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      3. flip-- N/A

         \[\leadsto \color{blue}{\frac{a \cdot a - \frac{1}{3} \cdot \frac{1}{3}}{a + \frac{1}{3}}} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

      4. associate-*l/ N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

      5. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

   4. Applied rewrites 65.6%

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - 0.1111111111111111\right) \cdot \mathsf{fma}\left(\frac{rand}{\sqrt{a - 0.3333333333333333}}, 0.3333333333333333, 1\right)}{a + 0.3333333333333333}} \]

   5. Taylor expanded in rand around 0

      \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]
   6. Step-by-step derivation

      1. lower-/.f64 N/A

         \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]

      2. lower--.f64 N/A

         \[\leadsto \frac{\color{blue}{{a}^{2} - \frac{1}{9}}}{\frac{1}{3} + a} \]

      3. unpow2 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      4. lower-*.f64 N/A

         \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

      5. lower-+.f64 35.0

         \[\leadsto \frac{a \cdot a - 0.1111111111111111}{\color{blue}{0.3333333333333333 + a}} \]

   7. Applied rewrites 35.0%

      \[\leadsto \color{blue}{\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333 + a}} \]

   8. Taylor expanded in a around 0

      \[\leadsto \frac{a \cdot a - \frac{1}{9}}{\frac{1}{3}} \]
   9. Step-by-step derivation

   10. Applied rewrites 36.0%

       \[\leadsto \frac{a \cdot a - 0.1111111111111111}{0.3333333333333333} \]
3. Recombined 2 regimes into one program.
4. Add Preprocessing

Alternative 6: 98.9% accurate, 2.7× speedup

Math

\[\begin{array}{l} \\ \mathsf{fma}\left(\sqrt{a} \cdot 0.3333333333333333, rand, a - 0.3333333333333333\right) \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (fma (* (sqrt a) 0.3333333333333333) rand (- a 0.3333333333333333)))

C

double code(double a, double rand) {
	return fma((sqrt(a) * 0.3333333333333333), rand, (a - 0.3333333333333333));
}

Julia

function code(a, rand)
	return fma(Float64(sqrt(a) * 0.3333333333333333), rand, Float64(a - 0.3333333333333333))
end

Wolfram

code[a_, rand_] := N[(N[(N[Sqrt[a], $MachinePrecision] * 0.3333333333333333), $MachinePrecision] * rand + N[(a - 0.3333333333333333), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 99.8%

   \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
2. Add Preprocessing
3. Step-by-step derivation

   1. lift-*.f64 N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   2. lift-+.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   3. +-commutative N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand + 1\right)} \]

   4. distribute-lft-in N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) + \left(a - \frac{1}{3}\right) \cdot 1} \]

   5. lift-*.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   6. associate-*r* N/A

      \[\leadsto \color{blue}{\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   7. *-rgt-identity N/A

      \[\leadsto \left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand + \color{blue}{\left(a - \frac{1}{3}\right)} \]

   8. lower-fma.f64 N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}, rand, a - \frac{1}{3}\right)} \]

4. Applied rewrites 99.8%

   \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.3333333333333333 \cdot \left(a - 0.3333333333333333\right)}{\sqrt{a - 0.3333333333333333}}, rand, a - 0.3333333333333333\right)} \]

5. Taylor expanded in a around inf

   \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{3} \cdot \sqrt{a}}, rand, a - \frac{1}{3}\right) \]
6. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a} \cdot \frac{1}{3}}, rand, a - \frac{1}{3}\right) \]

   2. lower-*.f64 N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a} \cdot \frac{1}{3}}, rand, a - \frac{1}{3}\right) \]

   3. lower-sqrt.f64 99.7

      \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a}} \cdot 0.3333333333333333, rand, a - 0.3333333333333333\right) \]

7. Applied rewrites 99.7%

   \[\leadsto \mathsf{fma}\left(\color{blue}{\sqrt{a} \cdot 0.3333333333333333}, rand, a - 0.3333333333333333\right) \]
8. Add Preprocessing

Alternative 7: 97.8% accurate, 3.1× speedup

Math

\[\begin{array}{l} \\ \mathsf{fma}\left(\sqrt{a} \cdot rand, 0.3333333333333333, a\right) \end{array} \]

FPCore

(FPCore (a rand)
 :precision binary64
 (fma (* (sqrt a) rand) 0.3333333333333333 a))

C

double code(double a, double rand) {
	return fma((sqrt(a) * rand), 0.3333333333333333, a);
}

Julia

function code(a, rand)
	return fma(Float64(sqrt(a) * rand), 0.3333333333333333, a)
end

Wolfram

code[a_, rand_] := N[(N[(N[Sqrt[a], $MachinePrecision] * rand), $MachinePrecision] * 0.3333333333333333 + a), $MachinePrecision]

Derivation

1. Initial program 99.8%

   \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
2. Add Preprocessing
3. Step-by-step derivation

   1. lift-*.f64 N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   2. lift-+.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   3. +-commutative N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand + 1\right)} \]

   4. distribute-lft-in N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) + \left(a - \frac{1}{3}\right) \cdot 1} \]

   5. lift-*.f64 N/A

      \[\leadsto \left(a - \frac{1}{3}\right) \cdot \color{blue}{\left(\frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   6. associate-*r* N/A

      \[\leadsto \color{blue}{\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand} + \left(a - \frac{1}{3}\right) \cdot 1 \]

   7. *-rgt-identity N/A

      \[\leadsto \left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}\right) \cdot rand + \color{blue}{\left(a - \frac{1}{3}\right)} \]

   8. lower-fma.f64 N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\left(a - \frac{1}{3}\right) \cdot \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}}, rand, a - \frac{1}{3}\right)} \]

4. Applied rewrites 99.8%

   \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.3333333333333333 \cdot \left(a - 0.3333333333333333\right)}{\sqrt{a - 0.3333333333333333}}, rand, a - 0.3333333333333333\right)} \]

5. Taylor expanded in a around inf

   \[\leadsto \color{blue}{a \cdot \left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right)} \]
6. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \color{blue}{\left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right) \cdot a} \]

   2. lower-*.f64 N/A

      \[\leadsto \color{blue}{\left(1 + \frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right)\right) \cdot a} \]

   3. +-commutative N/A

      \[\leadsto \color{blue}{\left(\frac{1}{3} \cdot \left(\sqrt{\frac{1}{a}} \cdot rand\right) + 1\right)} \cdot a \]

   4. *-commutative N/A

      \[\leadsto \left(\frac{1}{3} \cdot \color{blue}{\left(rand \cdot \sqrt{\frac{1}{a}}\right)} + 1\right) \cdot a \]

   5. associate-*r* N/A

      \[\leadsto \left(\color{blue}{\left(\frac{1}{3} \cdot rand\right) \cdot \sqrt{\frac{1}{a}}} + 1\right) \cdot a \]

   6. lower-fma.f64 N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{3} \cdot rand, \sqrt{\frac{1}{a}}, 1\right)} \cdot a \]

   7. lower-*.f64 N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{1}{3} \cdot rand}, \sqrt{\frac{1}{a}}, 1\right) \cdot a \]

   8. lower-sqrt.f64 N/A

      \[\leadsto \mathsf{fma}\left(\frac{1}{3} \cdot rand, \color{blue}{\sqrt{\frac{1}{a}}}, 1\right) \cdot a \]

   9. lower-/.f64 98.4

      \[\leadsto \mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{\color{blue}{\frac{1}{a}}}, 1\right) \cdot a \]

7. Applied rewrites 98.4%

   \[\leadsto \color{blue}{\mathsf{fma}\left(0.3333333333333333 \cdot rand, \sqrt{\frac{1}{a}}, 1\right) \cdot a} \]

8. Taylor expanded in a around 0

   \[\leadsto a + \color{blue}{\frac{1}{3} \cdot \left(\sqrt{a} \cdot rand\right)} \]
9. Step-by-step derivation

10. Applied rewrites 98.4%

    \[\leadsto \mathsf{fma}\left(\sqrt{a} \cdot rand, \color{blue}{0.3333333333333333}, a\right) \]
11. Add Preprocessing

Alternative 8: 62.9% accurate, 17.0× speedup

Math

\[\begin{array}{l} \\ a - 0.3333333333333333 \end{array} \]

FPCore

(FPCore (a rand) :precision binary64 (- a 0.3333333333333333))

C

double code(double a, double rand) {
	return a - 0.3333333333333333;
}

Fortran

real(8) function code(a, rand)
    real(8), intent (in) :: a
    real(8), intent (in) :: rand
    code = a - 0.3333333333333333d0
end function

Java

public static double code(double a, double rand) {
	return a - 0.3333333333333333;
}

Python

def code(a, rand):
	return a - 0.3333333333333333

Julia

function code(a, rand)
	return Float64(a - 0.3333333333333333)
end

MATLAB

function tmp = code(a, rand)
	tmp = a - 0.3333333333333333;
end

Wolfram

code[a_, rand_] := N[(a - 0.3333333333333333), $MachinePrecision]

Derivation

1. Initial program 99.8%

   \[\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]
2. Add Preprocessing
3. Step-by-step derivation

   1. lift-*.f64 N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)} \]

   2. lift--.f64 N/A

      \[\leadsto \color{blue}{\left(a - \frac{1}{3}\right)} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

   3. flip-- N/A

      \[\leadsto \color{blue}{\frac{a \cdot a - \frac{1}{3} \cdot \frac{1}{3}}{a + \frac{1}{3}}} \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right) \]

   4. associate-*l/ N/A

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

   5. lower-/.f64 N/A

      \[\leadsto \color{blue}{\frac{\left(a \cdot a - \frac{1}{3} \cdot \frac{1}{3}\right) \cdot \left(1 + \frac{1}{\sqrt{9 \cdot \left(a - \frac{1}{3}\right)}} \cdot rand\right)}{a + \frac{1}{3}}} \]

4. Applied rewrites 54.8%

   \[\leadsto \color{blue}{\frac{\left(a \cdot a - 0.1111111111111111\right) \cdot \mathsf{fma}\left(\frac{rand}{\sqrt{a - 0.3333333333333333}}, 0.3333333333333333, 1\right)}{a + 0.3333333333333333}} \]

5. Taylor expanded in rand around 0

   \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]
6. Step-by-step derivation

   1. lower-/.f64 N/A

      \[\leadsto \color{blue}{\frac{{a}^{2} - \frac{1}{9}}{\frac{1}{3} + a}} \]

   2. lower--.f64 N/A

      \[\leadsto \frac{\color{blue}{{a}^{2} - \frac{1}{9}}}{\frac{1}{3} + a} \]

   3. unpow2 N/A

      \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

   4. lower-*.f64 N/A

      \[\leadsto \frac{\color{blue}{a \cdot a} - \frac{1}{9}}{\frac{1}{3} + a} \]

   5. lower-+.f64 36.0

      \[\leadsto \frac{a \cdot a - 0.1111111111111111}{\color{blue}{0.3333333333333333 + a}} \]

7. Applied rewrites 36.0%

   \[\leadsto \color{blue}{\frac{a \cdot a - 0.1111111111111111}{0.3333333333333333 + a}} \]
8. Step-by-step derivation

9. Applied rewrites 63.2%

   \[\leadsto \color{blue}{a - 0.3333333333333333} \]
10. Add Preprocessing

Reproduce

herbie shell --seed 2024329 
(FPCore (a rand)
  :name "Octave 3.8, oct_fill_randg"
  :precision binary64
  (* (- a (/ 1.0 3.0)) (+ 1.0 (* (/ 1.0 (sqrt (* 9.0 (- a (/ 1.0 3.0))))) rand))))