
(FPCore (x y z) :precision binary64 (/ (* 4.0 (- (- x y) (* z 0.5))) z))
double code(double x, double y, double z) {
return (4.0 * ((x - y) - (z * 0.5))) / z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
end function
public static double code(double x, double y, double z) {
return (4.0 * ((x - y) - (z * 0.5))) / z;
}
def code(x, y, z): return (4.0 * ((x - y) - (z * 0.5))) / z
function code(x, y, z) return Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z) end
function tmp = code(x, y, z) tmp = (4.0 * ((x - y) - (z * 0.5))) / z; end
code[x_, y_, z_] := N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]
\begin{array}{l}
\\
\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z) :precision binary64 (/ (* 4.0 (- (- x y) (* z 0.5))) z))
double code(double x, double y, double z) {
return (4.0 * ((x - y) - (z * 0.5))) / z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
end function
public static double code(double x, double y, double z) {
return (4.0 * ((x - y) - (z * 0.5))) / z;
}
def code(x, y, z): return (4.0 * ((x - y) - (z * 0.5))) / z
function code(x, y, z) return Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z) end
function tmp = code(x, y, z) tmp = (4.0 * ((x - y) - (z * 0.5))) / z; end
code[x_, y_, z_] := N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]
\begin{array}{l}
\\
\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}
\end{array}
(FPCore (x y z) :precision binary64 (* -4.0 (- (/ (- y x) z) -0.5)))
double code(double x, double y, double z) {
return -4.0 * (((y - x) / z) - -0.5);
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (-4.0d0) * (((y - x) / z) - (-0.5d0))
end function
public static double code(double x, double y, double z) {
return -4.0 * (((y - x) / z) - -0.5);
}
def code(x, y, z): return -4.0 * (((y - x) / z) - -0.5)
function code(x, y, z) return Float64(-4.0 * Float64(Float64(Float64(y - x) / z) - -0.5)) end
function tmp = code(x, y, z) tmp = -4.0 * (((y - x) / z) - -0.5); end
code[x_, y_, z_] := N[(-4.0 * N[(N[(N[(y - x), $MachinePrecision] / z), $MachinePrecision] - -0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-4 \cdot \left(\frac{y - x}{z} - -0.5\right)
\end{array}
Initial program 100.0%
remove-double-neg100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
div-sub100.0%
distribute-frac-neg2100.0%
distribute-frac-neg100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-out100.0%
remove-double-neg100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
*-inverses100.0%
metadata-eval100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (x y z) :precision binary64 (if (<= y -1.3e+38) (* -4.0 (- (/ y z) -0.5)) (* -4.0 (- (/ x (- z)) -0.5))))
double code(double x, double y, double z) {
double tmp;
if (y <= -1.3e+38) {
tmp = -4.0 * ((y / z) - -0.5);
} else {
tmp = -4.0 * ((x / -z) - -0.5);
}
return tmp;
}
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 <= (-1.3d+38)) then
tmp = (-4.0d0) * ((y / z) - (-0.5d0))
else
tmp = (-4.0d0) * ((x / -z) - (-0.5d0))
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= -1.3e+38) {
tmp = -4.0 * ((y / z) - -0.5);
} else {
tmp = -4.0 * ((x / -z) - -0.5);
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= -1.3e+38: tmp = -4.0 * ((y / z) - -0.5) else: tmp = -4.0 * ((x / -z) - -0.5) return tmp
function code(x, y, z) tmp = 0.0 if (y <= -1.3e+38) tmp = Float64(-4.0 * Float64(Float64(y / z) - -0.5)); else tmp = Float64(-4.0 * Float64(Float64(x / Float64(-z)) - -0.5)); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= -1.3e+38) tmp = -4.0 * ((y / z) - -0.5); else tmp = -4.0 * ((x / -z) - -0.5); end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, -1.3e+38], N[(-4.0 * N[(N[(y / z), $MachinePrecision] - -0.5), $MachinePrecision]), $MachinePrecision], N[(-4.0 * N[(N[(x / (-z)), $MachinePrecision] - -0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.3 \cdot 10^{+38}:\\
\;\;\;\;-4 \cdot \left(\frac{y}{z} - -0.5\right)\\
\mathbf{else}:\\
\;\;\;\;-4 \cdot \left(\frac{x}{-z} - -0.5\right)\\
\end{array}
\end{array}
if y < -1.3e38Initial program 99.9%
remove-double-neg99.9%
neg-mul-199.9%
times-frac99.9%
metadata-eval99.9%
div-sub100.0%
distribute-frac-neg2100.0%
distribute-frac-neg100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-out100.0%
remove-double-neg100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
*-inverses100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in y around inf 88.1%
if -1.3e38 < y Initial program 100.0%
remove-double-neg100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
div-sub100.0%
distribute-frac-neg2100.0%
distribute-frac-neg100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-out100.0%
remove-double-neg100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
*-inverses100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in y around 0 79.4%
neg-mul-179.4%
distribute-neg-frac79.4%
Simplified79.4%
Final simplification81.3%
(FPCore (x y z) :precision binary64 (* -4.0 (- (/ y z) -0.5)))
double code(double x, double y, double z) {
return -4.0 * ((y / z) - -0.5);
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (-4.0d0) * ((y / z) - (-0.5d0))
end function
public static double code(double x, double y, double z) {
return -4.0 * ((y / z) - -0.5);
}
def code(x, y, z): return -4.0 * ((y / z) - -0.5)
function code(x, y, z) return Float64(-4.0 * Float64(Float64(y / z) - -0.5)) end
function tmp = code(x, y, z) tmp = -4.0 * ((y / z) - -0.5); end
code[x_, y_, z_] := N[(-4.0 * N[(N[(y / z), $MachinePrecision] - -0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-4 \cdot \left(\frac{y}{z} - -0.5\right)
\end{array}
Initial program 100.0%
remove-double-neg100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
div-sub100.0%
distribute-frac-neg2100.0%
distribute-frac-neg100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-out100.0%
remove-double-neg100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
*-inverses100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in y around inf 67.5%
Final simplification67.5%
(FPCore (x y z) :precision binary64 (- (* 4.0 (/ x z)) (+ 2.0 (* 4.0 (/ y z)))))
double code(double x, double y, double z) {
return (4.0 * (x / z)) - (2.0 + (4.0 * (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 = (4.0d0 * (x / z)) - (2.0d0 + (4.0d0 * (y / z)))
end function
public static double code(double x, double y, double z) {
return (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)));
}
def code(x, y, z): return (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)))
function code(x, y, z) return Float64(Float64(4.0 * Float64(x / z)) - Float64(2.0 + Float64(4.0 * Float64(y / z)))) end
function tmp = code(x, y, z) tmp = (4.0 * (x / z)) - (2.0 + (4.0 * (y / z))); end
code[x_, y_, z_] := N[(N[(4.0 * N[(x / z), $MachinePrecision]), $MachinePrecision] - N[(2.0 + N[(4.0 * N[(y / z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
4 \cdot \frac{x}{z} - \left(2 + 4 \cdot \frac{y}{z}\right)
\end{array}
herbie shell --seed 2024066
(FPCore (x y z)
:name "Data.Array.Repa.Algorithms.ColorRamp:rampColorHotToCold from repa-algorithms-3.4.0.1, B"
:precision binary64
:alt
(- (* 4.0 (/ x z)) (+ 2.0 (* 4.0 (/ y z))))
(/ (* 4.0 (- (- x y) (* z 0.5))) z))