
(FPCore (x y) :precision binary64 (+ x (/ (- y x) 2.0)))
double code(double x, double y) {
return x + ((y - x) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((y - x) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((y - x) / 2.0);
}
def code(x, y): return x + ((y - x) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(y - x) / 2.0)) end
function tmp = code(x, y) tmp = x + ((y - x) / 2.0); end
code[x_, y_] := N[(x + N[(N[(y - x), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{y - x}{2}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (+ x (/ (- y x) 2.0)))
double code(double x, double y) {
return x + ((y - x) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((y - x) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((y - x) / 2.0);
}
def code(x, y): return x + ((y - x) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(y - x) / 2.0)) end
function tmp = code(x, y) tmp = x + ((y - x) / 2.0); end
code[x_, y_] := N[(x + N[(N[(y - x), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{y - x}{2}
\end{array}
(FPCore (x y) :precision binary64 (* (+ y x) 0.5))
double code(double x, double y) {
return (y + x) * 0.5;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (y + x) * 0.5d0
end function
public static double code(double x, double y) {
return (y + x) * 0.5;
}
def code(x, y): return (y + x) * 0.5
function code(x, y) return Float64(Float64(y + x) * 0.5) end
function tmp = code(x, y) tmp = (y + x) * 0.5; end
code[x_, y_] := N[(N[(y + x), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(y + x\right) \cdot 0.5
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
*-commutativeN/A
fp-cancel-sign-sub-invN/A
distribute-lft-neg-outN/A
*-commutativeN/A
distribute-lft-neg-inN/A
*-rgt-identityN/A
*-inversesN/A
associate-/l*N/A
associate-*l/N/A
metadata-evalN/A
associate-*r/N/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
fp-cancel-sign-sub-invN/A
distribute-lft-outN/A
remove-double-negN/A
distribute-lft-neg-outN/A
mul-1-negN/A
*-commutativeN/A
distribute-lft-neg-inN/A
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (if (or (<= y -1.7e+39) (not (<= y 1e-13))) (* 0.5 y) (* 0.5 x)))
double code(double x, double y) {
double tmp;
if ((y <= -1.7e+39) || !(y <= 1e-13)) {
tmp = 0.5 * y;
} else {
tmp = 0.5 * x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((y <= (-1.7d+39)) .or. (.not. (y <= 1d-13))) then
tmp = 0.5d0 * y
else
tmp = 0.5d0 * x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -1.7e+39) || !(y <= 1e-13)) {
tmp = 0.5 * y;
} else {
tmp = 0.5 * x;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -1.7e+39) or not (y <= 1e-13): tmp = 0.5 * y else: tmp = 0.5 * x return tmp
function code(x, y) tmp = 0.0 if ((y <= -1.7e+39) || !(y <= 1e-13)) tmp = Float64(0.5 * y); else tmp = Float64(0.5 * x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -1.7e+39) || ~((y <= 1e-13))) tmp = 0.5 * y; else tmp = 0.5 * x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -1.7e+39], N[Not[LessEqual[y, 1e-13]], $MachinePrecision]], N[(0.5 * y), $MachinePrecision], N[(0.5 * x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.7 \cdot 10^{+39} \lor \neg \left(y \leq 10^{-13}\right):\\
\;\;\;\;0.5 \cdot y\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot x\\
\end{array}
\end{array}
if y < -1.6999999999999999e39 or 1e-13 < y Initial program 100.0%
Taylor expanded in x around 0
lower-*.f6478.4
Applied rewrites78.4%
if -1.6999999999999999e39 < y < 1e-13Initial program 99.9%
Taylor expanded in x around inf
lower-*.f6474.8
Applied rewrites74.8%
Final simplification76.5%
(FPCore (x y) :precision binary64 (* 0.5 x))
double code(double x, double y) {
return 0.5 * x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 0.5d0 * x
end function
public static double code(double x, double y) {
return 0.5 * x;
}
def code(x, y): return 0.5 * x
function code(x, y) return Float64(0.5 * x) end
function tmp = code(x, y) tmp = 0.5 * x; end
code[x_, y_] := N[(0.5 * x), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot x
\end{array}
Initial program 100.0%
Taylor expanded in x around inf
lower-*.f6450.2
Applied rewrites50.2%
(FPCore (x y) :precision binary64 (* 0.5 (+ x y)))
double code(double x, double y) {
return 0.5 * (x + y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 0.5d0 * (x + y)
end function
public static double code(double x, double y) {
return 0.5 * (x + y);
}
def code(x, y): return 0.5 * (x + y)
function code(x, y) return Float64(0.5 * Float64(x + y)) end
function tmp = code(x, y) tmp = 0.5 * (x + y); end
code[x_, y_] := N[(0.5 * N[(x + y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot \left(x + y\right)
\end{array}
herbie shell --seed 2024329
(FPCore (x y)
:name "Numeric.Interval.Internal:bisect from intervals-0.7.1, A"
:precision binary64
:alt
(! :herbie-platform default (* 1/2 (+ x y)))
(+ x (/ (- y x) 2.0)))