Graphics.Rasterific.Linear:$cquadrance from Rasterific-0.6.1

Percentage Accurate: 100.0% → 100.0%
Time: 3.0s
Alternatives: 2
Speedup: 1.0×

Specification

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

\\
x \cdot x + y \cdot y
\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 2 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: 100.0% accurate, 1.0× speedup?

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

\\
x \cdot x + y \cdot y
\end{array}

Alternative 1: 100.0% accurate, 0.1× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ y_m = \left|y\right| \\ [x_m, y_m] = \mathsf{sort}([x_m, y_m])\\ \\ \mathsf{fma}\left(y\_m, y\_m, x\_m \cdot x\_m\right) \end{array} \]
x_m = (fabs.f64 x)
y_m = (fabs.f64 y)
NOTE: x_m and y_m should be sorted in increasing order before calling this function.
(FPCore (x_m y_m) :precision binary64 (fma y_m y_m (* x_m x_m)))
x_m = fabs(x);
y_m = fabs(y);
assert(x_m < y_m);
double code(double x_m, double y_m) {
	return fma(y_m, y_m, (x_m * x_m));
}
x_m = abs(x)
y_m = abs(y)
x_m, y_m = sort([x_m, y_m])
function code(x_m, y_m)
	return fma(y_m, y_m, Float64(x_m * x_m))
end
x_m = N[Abs[x], $MachinePrecision]
y_m = N[Abs[y], $MachinePrecision]
NOTE: x_m and y_m should be sorted in increasing order before calling this function.
code[x$95$m_, y$95$m_] := N[(y$95$m * y$95$m + N[(x$95$m * x$95$m), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
y_m = \left|y\right|
\\
[x_m, y_m] = \mathsf{sort}([x_m, y_m])\\
\\
\mathsf{fma}\left(y\_m, y\_m, x\_m \cdot x\_m\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[x \cdot x + y \cdot y \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. +-commutative100.0%

      \[\leadsto \color{blue}{y \cdot y + x \cdot x} \]
    2. fma-define100.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(y, y, x \cdot x\right)} \]
    3. pow2100.0%

      \[\leadsto \mathsf{fma}\left(y, y, \color{blue}{{x}^{2}}\right) \]
  4. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(y, y, {x}^{2}\right)} \]
  5. Step-by-step derivation
    1. unpow2100.0%

      \[\leadsto \mathsf{fma}\left(y, y, \color{blue}{x \cdot x}\right) \]
  6. Applied egg-rr100.0%

    \[\leadsto \mathsf{fma}\left(y, y, \color{blue}{x \cdot x}\right) \]
  7. Add Preprocessing

Alternative 2: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ y_m = \left|y\right| \\ [x_m, y_m] = \mathsf{sort}([x_m, y_m])\\ \\ x\_m \cdot x\_m + y\_m \cdot y\_m \end{array} \]
x_m = (fabs.f64 x)
y_m = (fabs.f64 y)
NOTE: x_m and y_m should be sorted in increasing order before calling this function.
(FPCore (x_m y_m) :precision binary64 (+ (* x_m x_m) (* y_m y_m)))
x_m = fabs(x);
y_m = fabs(y);
assert(x_m < y_m);
double code(double x_m, double y_m) {
	return (x_m * x_m) + (y_m * y_m);
}
x_m = abs(x)
y_m = abs(y)
NOTE: x_m and y_m should be sorted in increasing order before calling this function.
real(8) function code(x_m, y_m)
    real(8), intent (in) :: x_m
    real(8), intent (in) :: y_m
    code = (x_m * x_m) + (y_m * y_m)
end function
x_m = Math.abs(x);
y_m = Math.abs(y);
assert x_m < y_m;
public static double code(double x_m, double y_m) {
	return (x_m * x_m) + (y_m * y_m);
}
x_m = math.fabs(x)
y_m = math.fabs(y)
[x_m, y_m] = sort([x_m, y_m])
def code(x_m, y_m):
	return (x_m * x_m) + (y_m * y_m)
x_m = abs(x)
y_m = abs(y)
x_m, y_m = sort([x_m, y_m])
function code(x_m, y_m)
	return Float64(Float64(x_m * x_m) + Float64(y_m * y_m))
end
x_m = abs(x);
y_m = abs(y);
x_m, y_m = num2cell(sort([x_m, y_m])){:}
function tmp = code(x_m, y_m)
	tmp = (x_m * x_m) + (y_m * y_m);
end
x_m = N[Abs[x], $MachinePrecision]
y_m = N[Abs[y], $MachinePrecision]
NOTE: x_m and y_m should be sorted in increasing order before calling this function.
code[x$95$m_, y$95$m_] := N[(N[(x$95$m * x$95$m), $MachinePrecision] + N[(y$95$m * y$95$m), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
y_m = \left|y\right|
\\
[x_m, y_m] = \mathsf{sort}([x_m, y_m])\\
\\
x\_m \cdot x\_m + y\_m \cdot y\_m
\end{array}
Derivation
  1. Initial program 100.0%

    \[x \cdot x + y \cdot y \]
  2. Add Preprocessing
  3. Add Preprocessing

Reproduce

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herbie shell --seed 2024180 
(FPCore (x y)
  :name "Graphics.Rasterific.Linear:$cquadrance from Rasterific-0.6.1"
  :precision binary64
  (+ (* x x) (* y y)))