ENA, Section 1.4, Mentioned, A

Percentage Accurate: 53.6% → 100.0%

Time: 7.0s

Alternatives: 6

Speedup: 1.0×

Specification

\[-0.01 \leq x \land x \leq 0.01\]

Math

\[\begin{array}{l} \\ 1 - \cos x \end{array} \]

FPCore

(FPCore (x) :precision binary64 (- 1.0 (cos x)))

C

double code(double x) {
	return 1.0 - cos(x);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - cos(x)
end function

Java

public static double code(double x) {
	return 1.0 - Math.cos(x);
}

Python

def code(x):
	return 1.0 - math.cos(x)

Julia

function code(x)
	return Float64(1.0 - cos(x))
end

MATLAB

function tmp = code(x)
	tmp = 1.0 - cos(x);
end

Wolfram

code[x_] := N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision]

Initial Program: 53.6% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ 1 - \cos x \end{array} \]

FPCore

(FPCore (x) :precision binary64 (- 1.0 (cos x)))

C

double code(double x) {
	return 1.0 - cos(x);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - cos(x)
end function

Java

public static double code(double x) {
	return 1.0 - Math.cos(x);
}

Python

def code(x):
	return 1.0 - math.cos(x)

Julia

function code(x)
	return Float64(1.0 - cos(x))
end

MATLAB

function tmp = code(x)
	tmp = 1.0 - cos(x);
end

Wolfram

code[x_] := N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision]

Alternative 1: 100.0% accurate, 0.3× speedup

Math

\[\begin{array}{l} \\ {\sin x}^{2} \cdot \frac{1}{1 + \cos x} \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* (pow (sin x) 2.0) (/ 1.0 (+ 1.0 (cos x)))))

C

double code(double x) {
	return pow(sin(x), 2.0) * (1.0 / (1.0 + cos(x)));
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = (sin(x) ** 2.0d0) * (1.0d0 / (1.0d0 + cos(x)))
end function

Java

public static double code(double x) {
	return Math.pow(Math.sin(x), 2.0) * (1.0 / (1.0 + Math.cos(x)));
}

Python

def code(x):
	return math.pow(math.sin(x), 2.0) * (1.0 / (1.0 + math.cos(x)))

Julia

function code(x)
	return Float64((sin(x) ^ 2.0) * Float64(1.0 / Float64(1.0 + cos(x))))
end

MATLAB

function tmp = code(x)
	tmp = (sin(x) ^ 2.0) * (1.0 / (1.0 + cos(x)));
end

Wolfram

code[x_] := N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] * N[(1.0 / N[(1.0 + N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing
3. Step-by-step derivation

   1. flip-- 55.8%

      \[\leadsto \color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}} \]

   2. div-inv 55.8%

      \[\leadsto \color{blue}{\left(1 \cdot 1 - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x}} \]

   3. metadata-eval 55.8%

      \[\leadsto \left(\color{blue}{1} - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x} \]

   4. 1-sub-cos 100.0%

      \[\leadsto \color{blue}{\left(\sin x \cdot \sin x\right)} \cdot \frac{1}{1 + \cos x} \]

   5. pow2 100.0%

      \[\leadsto \color{blue}{{\sin x}^{2}} \cdot \frac{1}{1 + \cos x} \]

4. Applied egg-rr 100.0%

   \[\leadsto \color{blue}{{\sin x}^{2} \cdot \frac{1}{1 + \cos x}} \]

5. Final simplification 100.0%

   \[\leadsto {\sin x}^{2} \cdot \frac{1}{1 + \cos x} \]
6. Add Preprocessing

Alternative 2: 100.0% accurate, 0.5× speedup

Math

\[\begin{array}{l} \\ \sin x \cdot \tan \left(\frac{x}{2}\right) \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* (sin x) (tan (/ x 2.0))))

C

double code(double x) {
	return sin(x) * tan((x / 2.0));
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = sin(x) * tan((x / 2.0d0))
end function

Java

public static double code(double x) {
	return Math.sin(x) * Math.tan((x / 2.0));
}

Python

def code(x):
	return math.sin(x) * math.tan((x / 2.0))

Julia

function code(x)
	return Float64(sin(x) * tan(Float64(x / 2.0)))
end

MATLAB

function tmp = code(x)
	tmp = sin(x) * tan((x / 2.0));
end

Wolfram

code[x_] := N[(N[Sin[x], $MachinePrecision] * N[Tan[N[(x / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing
3. Step-by-step derivation

   1. flip-- 55.8%

      \[\leadsto \color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}} \]

   2. div-inv 55.8%

      \[\leadsto \color{blue}{\left(1 \cdot 1 - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x}} \]

   3. metadata-eval 55.8%

      \[\leadsto \left(\color{blue}{1} - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x} \]

   4. 1-sub-cos 100.0%

      \[\leadsto \color{blue}{\left(\sin x \cdot \sin x\right)} \cdot \frac{1}{1 + \cos x} \]

   5. pow2 100.0%

      \[\leadsto \color{blue}{{\sin x}^{2}} \cdot \frac{1}{1 + \cos x} \]

4. Applied egg-rr 100.0%

   \[\leadsto \color{blue}{{\sin x}^{2} \cdot \frac{1}{1 + \cos x}} \]
5. Step-by-step derivation

   1. associate-*r/ 100.0%

      \[\leadsto \color{blue}{\frac{{\sin x}^{2} \cdot 1}{1 + \cos x}} \]

   2. *-rgt-identity 100.0%

      \[\leadsto \frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x} \]

   3. unpow2 100.0%

      \[\leadsto \frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x} \]

   4. associate-/l* 100.0%

      \[\leadsto \color{blue}{\sin x \cdot \frac{\sin x}{1 + \cos x}} \]

   5. hang-0p-tan 100.0%

      \[\leadsto \sin x \cdot \color{blue}{\tan \left(\frac{x}{2}\right)} \]

6. Simplified 100.0%

   \[\leadsto \color{blue}{\sin x \cdot \tan \left(\frac{x}{2}\right)} \]

7. Final simplification 100.0%

   \[\leadsto \sin x \cdot \tan \left(\frac{x}{2}\right) \]
8. Add Preprocessing

Alternative 3: 99.6% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ \sin x \cdot \left(x \cdot 0.5\right) \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* (sin x) (* x 0.5)))

C

double code(double x) {
	return sin(x) * (x * 0.5);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = sin(x) * (x * 0.5d0)
end function

Java

public static double code(double x) {
	return Math.sin(x) * (x * 0.5);
}

Python

def code(x):
	return math.sin(x) * (x * 0.5)

Julia

function code(x)
	return Float64(sin(x) * Float64(x * 0.5))
end

MATLAB

function tmp = code(x)
	tmp = sin(x) * (x * 0.5);
end

Wolfram

code[x_] := N[(N[Sin[x], $MachinePrecision] * N[(x * 0.5), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing
3. Step-by-step derivation

   1. flip-- 55.8%

      \[\leadsto \color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}} \]

   2. div-inv 55.8%

      \[\leadsto \color{blue}{\left(1 \cdot 1 - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x}} \]

   3. metadata-eval 55.8%

      \[\leadsto \left(\color{blue}{1} - \cos x \cdot \cos x\right) \cdot \frac{1}{1 + \cos x} \]

   4. 1-sub-cos 100.0%

      \[\leadsto \color{blue}{\left(\sin x \cdot \sin x\right)} \cdot \frac{1}{1 + \cos x} \]

   5. pow2 100.0%

      \[\leadsto \color{blue}{{\sin x}^{2}} \cdot \frac{1}{1 + \cos x} \]

4. Applied egg-rr 100.0%

   \[\leadsto \color{blue}{{\sin x}^{2} \cdot \frac{1}{1 + \cos x}} \]
5. Step-by-step derivation

   1. associate-*r/ 100.0%

      \[\leadsto \color{blue}{\frac{{\sin x}^{2} \cdot 1}{1 + \cos x}} \]

   2. *-rgt-identity 100.0%

      \[\leadsto \frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x} \]

   3. unpow2 100.0%

      \[\leadsto \frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x} \]

   4. associate-/l* 100.0%

      \[\leadsto \color{blue}{\sin x \cdot \frac{\sin x}{1 + \cos x}} \]

   5. hang-0p-tan 100.0%

      \[\leadsto \sin x \cdot \color{blue}{\tan \left(\frac{x}{2}\right)} \]

6. Simplified 100.0%

   \[\leadsto \color{blue}{\sin x \cdot \tan \left(\frac{x}{2}\right)} \]

7. Taylor expanded in x around 0 99.5%

   \[\leadsto \sin x \cdot \color{blue}{\left(0.5 \cdot x\right)} \]

8. Final simplification 99.5%

   \[\leadsto \sin x \cdot \left(x \cdot 0.5\right) \]
9. Add Preprocessing

Alternative 4: 99.5% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ 0.5 \cdot {x}^{2} \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* 0.5 (pow x 2.0)))

C

double code(double x) {
	return 0.5 * pow(x, 2.0);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.5d0 * (x ** 2.0d0)
end function

Java

public static double code(double x) {
	return 0.5 * Math.pow(x, 2.0);
}

Python

def code(x):
	return 0.5 * math.pow(x, 2.0)

Julia

function code(x)
	return Float64(0.5 * (x ^ 2.0))
end

MATLAB

function tmp = code(x)
	tmp = 0.5 * (x ^ 2.0);
end

Wolfram

code[x_] := N[(0.5 * N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing

3. Taylor expanded in x around 0 99.5%

   \[\leadsto \color{blue}{0.5 \cdot {x}^{2}} \]

4. Final simplification 99.5%

   \[\leadsto 0.5 \cdot {x}^{2} \]
5. Add Preprocessing

Alternative 5: 53.6% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ 1 - \cos x \end{array} \]

FPCore

(FPCore (x) :precision binary64 (- 1.0 (cos x)))

C

double code(double x) {
	return 1.0 - cos(x);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - cos(x)
end function

Java

public static double code(double x) {
	return 1.0 - Math.cos(x);
}

Python

def code(x):
	return 1.0 - math.cos(x)

Julia

function code(x)
	return Float64(1.0 - cos(x))
end

MATLAB

function tmp = code(x)
	tmp = 1.0 - cos(x);
end

Wolfram

code[x_] := N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing

3. Final simplification 55.8%

   \[\leadsto 1 - \cos x \]
4. Add Preprocessing

Alternative 6: 4.1% accurate, 103.0× speedup

Math

\[\begin{array}{l} \\ 6 \end{array} \]

FPCore

(FPCore (x) :precision binary64 6.0)

C

double code(double x) {
	return 6.0;
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = 6.0d0
end function

Java

public static double code(double x) {
	return 6.0;
}

Python

def code(x):
	return 6.0

Julia

function code(x)
	return 6.0
end

MATLAB

function tmp = code(x)
	tmp = 6.0;
end

Wolfram

code[x_] := 6.0

Derivation

1. Initial program 55.8%

   \[1 - \cos x \]
2. Add Preprocessing
3. Step-by-step derivation

   1. flip-- 55.8%

      \[\leadsto \color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}} \]

   2. clear-num 55.8%

      \[\leadsto \color{blue}{\frac{1}{\frac{1 + \cos x}{1 \cdot 1 - \cos x \cdot \cos x}}} \]

   3. metadata-eval 55.8%

      \[\leadsto \frac{1}{\frac{1 + \cos x}{\color{blue}{1} - \cos x \cdot \cos x}} \]

   4. 1-sub-cos 99.3%

      \[\leadsto \frac{1}{\frac{1 + \cos x}{\color{blue}{\sin x \cdot \sin x}}} \]

   5. pow2 99.3%

      \[\leadsto \frac{1}{\frac{1 + \cos x}{\color{blue}{{\sin x}^{2}}}} \]

4. Applied egg-rr 99.3%

   \[\leadsto \color{blue}{\frac{1}{\frac{1 + \cos x}{{\sin x}^{2}}}} \]

5. Taylor expanded in x around 0 99.3%

   \[\leadsto \frac{1}{\color{blue}{\frac{2 + 0.16666666666666666 \cdot {x}^{2}}{{x}^{2}}}} \]
6. Step-by-step derivation

   1. *-commutative 99.3%

      \[\leadsto \frac{1}{\frac{2 + \color{blue}{{x}^{2} \cdot 0.16666666666666666}}{{x}^{2}}} \]

7. Simplified 99.3%

   \[\leadsto \frac{1}{\color{blue}{\frac{2 + {x}^{2} \cdot 0.16666666666666666}{{x}^{2}}}} \]

8. Taylor expanded in x around inf 4.2%

   \[\leadsto \color{blue}{6} \]

9. Final simplification 4.2%

   \[\leadsto 6 \]
10. Add Preprocessing

Developer target: 100.0% accurate, 0.3× speedup

Math

\[\begin{array}{l} \\ \frac{\sin x \cdot \sin x}{1 + \cos x} \end{array} \]

FPCore

(FPCore (x) :precision binary64 (/ (* (sin x) (sin x)) (+ 1.0 (cos x))))

C

double code(double x) {
	return (sin(x) * sin(x)) / (1.0 + cos(x));
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = (sin(x) * sin(x)) / (1.0d0 + cos(x))
end function

Java

public static double code(double x) {
	return (Math.sin(x) * Math.sin(x)) / (1.0 + Math.cos(x));
}

Python

def code(x):
	return (math.sin(x) * math.sin(x)) / (1.0 + math.cos(x))

Julia

function code(x)
	return Float64(Float64(sin(x) * sin(x)) / Float64(1.0 + cos(x)))
end

MATLAB

function tmp = code(x)
	tmp = (sin(x) * sin(x)) / (1.0 + cos(x));
end

Wolfram

code[x_] := N[(N[(N[Sin[x], $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Reproduce

herbie shell --seed 2024057 
(FPCore (x)
  :name "ENA, Section 1.4, Mentioned, A"
  :precision binary64
  :pre (and (<= -0.01 x) (<= x 0.01))

  :alt
  (/ (* (sin x) (sin x)) (+ 1.0 (cos x)))

  (- 1.0 (cos x)))