Data.Colour.RGBSpace.HSV:hsv from colour-2.3.3, I

Percentage Accurate: 95.9% → 99.2%
Time: 10.2s
Alternatives: 5
Speedup: 0.4×

Specification

?
\[\begin{array}{l} \\ x \cdot \left(1 - y \cdot z\right) \end{array} \]
(FPCore (x y z) :precision binary64 (* x (- 1.0 (* y z))))
double code(double x, double y, double z) {
	return x * (1.0 - (y * z));
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = x * (1.0d0 - (y * z))
end function
public static double code(double x, double y, double z) {
	return x * (1.0 - (y * z));
}
def code(x, y, z):
	return x * (1.0 - (y * z))
function code(x, y, z)
	return Float64(x * Float64(1.0 - Float64(y * z)))
end
function tmp = code(x, y, z)
	tmp = x * (1.0 - (y * z));
end
code[x_, y_, z_] := N[(x * N[(1.0 - N[(y * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(1 - y \cdot z\right)
\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 5 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: 95.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ x \cdot \left(1 - y \cdot z\right) \end{array} \]
(FPCore (x y z) :precision binary64 (* x (- 1.0 (* y z))))
double code(double x, double y, double z) {
	return x * (1.0 - (y * z));
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = x * (1.0d0 - (y * z))
end function
public static double code(double x, double y, double z) {
	return x * (1.0 - (y * z));
}
def code(x, y, z):
	return x * (1.0 - (y * z))
function code(x, y, z)
	return Float64(x * Float64(1.0 - Float64(y * z)))
end
function tmp = code(x, y, z)
	tmp = x * (1.0 - (y * z));
end
code[x_, y_, z_] := N[(x * N[(1.0 - N[(y * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(1 - y \cdot z\right)
\end{array}

Alternative 1: 99.2% accurate, 0.4× speedup?

\[\begin{array}{l} [x, y, z] = \mathsf{sort}([x, y, z])\\ \\ \begin{array}{l} t_0 := y \cdot \left(x \cdot \left(-z\right)\right)\\ \mathbf{if}\;y \cdot z \leq -1 \cdot 10^{+174}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \cdot z \leq 2 \cdot 10^{+89}:\\ \;\;\;\;x \cdot \left(1 - y \cdot z\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
NOTE: x, y, and z should be sorted in increasing order before calling this function.
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* y (* x (- z)))))
   (if (<= (* y z) -1e+174)
     t_0
     (if (<= (* y z) 2e+89) (* x (- 1.0 (* y z))) t_0))))
assert(x < y && y < z);
double code(double x, double y, double z) {
	double t_0 = y * (x * -z);
	double tmp;
	if ((y * z) <= -1e+174) {
		tmp = t_0;
	} else if ((y * z) <= 2e+89) {
		tmp = x * (1.0 - (y * z));
	} else {
		tmp = t_0;
	}
	return tmp;
}
NOTE: x, y, and z should be sorted in increasing order before calling this function.
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: t_0
    real(8) :: tmp
    t_0 = y * (x * -z)
    if ((y * z) <= (-1d+174)) then
        tmp = t_0
    else if ((y * z) <= 2d+89) then
        tmp = x * (1.0d0 - (y * z))
    else
        tmp = t_0
    end if
    code = tmp
end function
assert x < y && y < z;
public static double code(double x, double y, double z) {
	double t_0 = y * (x * -z);
	double tmp;
	if ((y * z) <= -1e+174) {
		tmp = t_0;
	} else if ((y * z) <= 2e+89) {
		tmp = x * (1.0 - (y * z));
	} else {
		tmp = t_0;
	}
	return tmp;
}
[x, y, z] = sort([x, y, z])
def code(x, y, z):
	t_0 = y * (x * -z)
	tmp = 0
	if (y * z) <= -1e+174:
		tmp = t_0
	elif (y * z) <= 2e+89:
		tmp = x * (1.0 - (y * z))
	else:
		tmp = t_0
	return tmp
x, y, z = sort([x, y, z])
function code(x, y, z)
	t_0 = Float64(y * Float64(x * Float64(-z)))
	tmp = 0.0
	if (Float64(y * z) <= -1e+174)
		tmp = t_0;
	elseif (Float64(y * z) <= 2e+89)
		tmp = Float64(x * Float64(1.0 - Float64(y * z)));
	else
		tmp = t_0;
	end
	return tmp
end
x, y, z = num2cell(sort([x, y, z])){:}
function tmp_2 = code(x, y, z)
	t_0 = y * (x * -z);
	tmp = 0.0;
	if ((y * z) <= -1e+174)
		tmp = t_0;
	elseif ((y * z) <= 2e+89)
		tmp = x * (1.0 - (y * z));
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
NOTE: x, y, and z should be sorted in increasing order before calling this function.
code[x_, y_, z_] := Block[{t$95$0 = N[(y * N[(x * (-z)), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(y * z), $MachinePrecision], -1e+174], t$95$0, If[LessEqual[N[(y * z), $MachinePrecision], 2e+89], N[(x * N[(1.0 - N[(y * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}
[x, y, z] = \mathsf{sort}([x, y, z])\\
\\
\begin{array}{l}
t_0 := y \cdot \left(x \cdot \left(-z\right)\right)\\
\mathbf{if}\;y \cdot z \leq -1 \cdot 10^{+174}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \cdot z \leq 2 \cdot 10^{+89}:\\
\;\;\;\;x \cdot \left(1 - y \cdot z\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 y z) < -1.00000000000000007e174 or 1.99999999999999999e89 < (*.f64 y z)

    1. Initial program 85.9%

      \[x \cdot \left(1 - y \cdot z\right) \]
    2. Add Preprocessing
    3. Taylor expanded in z around inf

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \left(y \cdot z\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot x\right) \cdot \left(y \cdot z\right)} \]
      2. *-commutativeN/A

        \[\leadsto \left(-1 \cdot x\right) \cdot \color{blue}{\left(z \cdot y\right)} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(-1 \cdot x\right) \cdot z\right) \cdot y} \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot z\right)\right)} \cdot y \]
      5. *-commutativeN/A

        \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
      7. mul-1-negN/A

        \[\leadsto y \cdot \color{blue}{\left(\mathsf{neg}\left(x \cdot z\right)\right)} \]
      8. distribute-rgt-neg-inN/A

        \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(\mathsf{neg}\left(z\right)\right)\right)} \]
      9. mul-1-negN/A

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-1 \cdot z\right)}\right) \]
      10. lower-*.f64N/A

        \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(-1 \cdot z\right)\right)} \]
      11. mul-1-negN/A

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(z\right)\right)}\right) \]
      12. lower-neg.f6499.9

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-z\right)}\right) \]
    5. Applied rewrites99.9%

      \[\leadsto \color{blue}{y \cdot \left(x \cdot \left(-z\right)\right)} \]

    if -1.00000000000000007e174 < (*.f64 y z) < 1.99999999999999999e89

    1. Initial program 99.9%

      \[x \cdot \left(1 - y \cdot z\right) \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 94.1% accurate, 0.4× speedup?

\[\begin{array}{l} [x, y, z] = \mathsf{sort}([x, y, z])\\ \\ \begin{array}{l} \mathbf{if}\;y \cdot z \leq -4.2:\\ \;\;\;\;\left(x \cdot \left(-y\right)\right) \cdot z\\ \mathbf{elif}\;y \cdot z \leq 0.002:\\ \;\;\;\;x \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot \left(x \cdot \left(-z\right)\right)\\ \end{array} \end{array} \]
NOTE: x, y, and z should be sorted in increasing order before calling this function.
(FPCore (x y z)
 :precision binary64
 (if (<= (* y z) -4.2)
   (* (* x (- y)) z)
   (if (<= (* y z) 0.002) (* x 1.0) (* y (* x (- z))))))
assert(x < y && y < z);
double code(double x, double y, double z) {
	double tmp;
	if ((y * z) <= -4.2) {
		tmp = (x * -y) * z;
	} else if ((y * z) <= 0.002) {
		tmp = x * 1.0;
	} else {
		tmp = y * (x * -z);
	}
	return tmp;
}
NOTE: x, y, and z should be sorted in increasing order before calling this function.
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if ((y * z) <= (-4.2d0)) then
        tmp = (x * -y) * z
    else if ((y * z) <= 0.002d0) then
        tmp = x * 1.0d0
    else
        tmp = y * (x * -z)
    end if
    code = tmp
end function
assert x < y && y < z;
public static double code(double x, double y, double z) {
	double tmp;
	if ((y * z) <= -4.2) {
		tmp = (x * -y) * z;
	} else if ((y * z) <= 0.002) {
		tmp = x * 1.0;
	} else {
		tmp = y * (x * -z);
	}
	return tmp;
}
[x, y, z] = sort([x, y, z])
def code(x, y, z):
	tmp = 0
	if (y * z) <= -4.2:
		tmp = (x * -y) * z
	elif (y * z) <= 0.002:
		tmp = x * 1.0
	else:
		tmp = y * (x * -z)
	return tmp
x, y, z = sort([x, y, z])
function code(x, y, z)
	tmp = 0.0
	if (Float64(y * z) <= -4.2)
		tmp = Float64(Float64(x * Float64(-y)) * z);
	elseif (Float64(y * z) <= 0.002)
		tmp = Float64(x * 1.0);
	else
		tmp = Float64(y * Float64(x * Float64(-z)));
	end
	return tmp
end
x, y, z = num2cell(sort([x, y, z])){:}
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if ((y * z) <= -4.2)
		tmp = (x * -y) * z;
	elseif ((y * z) <= 0.002)
		tmp = x * 1.0;
	else
		tmp = y * (x * -z);
	end
	tmp_2 = tmp;
end
NOTE: x, y, and z should be sorted in increasing order before calling this function.
code[x_, y_, z_] := If[LessEqual[N[(y * z), $MachinePrecision], -4.2], N[(N[(x * (-y)), $MachinePrecision] * z), $MachinePrecision], If[LessEqual[N[(y * z), $MachinePrecision], 0.002], N[(x * 1.0), $MachinePrecision], N[(y * N[(x * (-z)), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
[x, y, z] = \mathsf{sort}([x, y, z])\\
\\
\begin{array}{l}
\mathbf{if}\;y \cdot z \leq -4.2:\\
\;\;\;\;\left(x \cdot \left(-y\right)\right) \cdot z\\

\mathbf{elif}\;y \cdot z \leq 0.002:\\
\;\;\;\;x \cdot 1\\

\mathbf{else}:\\
\;\;\;\;y \cdot \left(x \cdot \left(-z\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 y z) < -4.20000000000000018

    1. Initial program 91.9%

      \[x \cdot \left(1 - y \cdot z\right) \]
    2. Add Preprocessing
    3. Taylor expanded in z around inf

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \left(y \cdot z\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot x\right) \cdot \left(y \cdot z\right)} \]
      2. *-commutativeN/A

        \[\leadsto \left(-1 \cdot x\right) \cdot \color{blue}{\left(z \cdot y\right)} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(-1 \cdot x\right) \cdot z\right) \cdot y} \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot z\right)\right)} \cdot y \]
      5. *-commutativeN/A

        \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
      7. mul-1-negN/A

        \[\leadsto y \cdot \color{blue}{\left(\mathsf{neg}\left(x \cdot z\right)\right)} \]
      8. distribute-rgt-neg-inN/A

        \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(\mathsf{neg}\left(z\right)\right)\right)} \]
      9. mul-1-negN/A

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-1 \cdot z\right)}\right) \]
      10. lower-*.f64N/A

        \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(-1 \cdot z\right)\right)} \]
      11. mul-1-negN/A

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(z\right)\right)}\right) \]
      12. lower-neg.f6490.5

        \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-z\right)}\right) \]
    5. Applied rewrites90.5%

      \[\leadsto \color{blue}{y \cdot \left(x \cdot \left(-z\right)\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites90.2%

        \[\leadsto \left(x \cdot y\right) \cdot \color{blue}{\left(-z\right)} \]

      if -4.20000000000000018 < (*.f64 y z) < 2e-3

      1. Initial program 100.0%

        \[x \cdot \left(1 - y \cdot z\right) \]
      2. Add Preprocessing
      3. Taylor expanded in z around 0

        \[\leadsto x \cdot \color{blue}{1} \]
      4. Step-by-step derivation
        1. Applied rewrites97.9%

          \[\leadsto x \cdot \color{blue}{1} \]

        if 2e-3 < (*.f64 y z)

        1. Initial program 91.6%

          \[x \cdot \left(1 - y \cdot z\right) \]
        2. Add Preprocessing
        3. Taylor expanded in z around inf

          \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \left(y \cdot z\right)\right)} \]
        4. Step-by-step derivation
          1. associate-*r*N/A

            \[\leadsto \color{blue}{\left(-1 \cdot x\right) \cdot \left(y \cdot z\right)} \]
          2. *-commutativeN/A

            \[\leadsto \left(-1 \cdot x\right) \cdot \color{blue}{\left(z \cdot y\right)} \]
          3. associate-*r*N/A

            \[\leadsto \color{blue}{\left(\left(-1 \cdot x\right) \cdot z\right) \cdot y} \]
          4. associate-*r*N/A

            \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot z\right)\right)} \cdot y \]
          5. *-commutativeN/A

            \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
          6. lower-*.f64N/A

            \[\leadsto \color{blue}{y \cdot \left(-1 \cdot \left(x \cdot z\right)\right)} \]
          7. mul-1-negN/A

            \[\leadsto y \cdot \color{blue}{\left(\mathsf{neg}\left(x \cdot z\right)\right)} \]
          8. distribute-rgt-neg-inN/A

            \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(\mathsf{neg}\left(z\right)\right)\right)} \]
          9. mul-1-negN/A

            \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-1 \cdot z\right)}\right) \]
          10. lower-*.f64N/A

            \[\leadsto y \cdot \color{blue}{\left(x \cdot \left(-1 \cdot z\right)\right)} \]
          11. mul-1-negN/A

            \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(z\right)\right)}\right) \]
          12. lower-neg.f6490.1

            \[\leadsto y \cdot \left(x \cdot \color{blue}{\left(-z\right)}\right) \]
        5. Applied rewrites90.1%

          \[\leadsto \color{blue}{y \cdot \left(x \cdot \left(-z\right)\right)} \]
      5. Recombined 3 regimes into one program.
      6. Final simplification94.1%

        \[\leadsto \begin{array}{l} \mathbf{if}\;y \cdot z \leq -4.2:\\ \;\;\;\;\left(x \cdot \left(-y\right)\right) \cdot z\\ \mathbf{elif}\;y \cdot z \leq 0.002:\\ \;\;\;\;x \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot \left(x \cdot \left(-z\right)\right)\\ \end{array} \]
      7. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2024229 
      (FPCore (x y z)
        :name "Data.Colour.RGBSpace.HSV:hsv from colour-2.3.3, I"
        :precision binary64
        (* x (- 1.0 (* y z))))