
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
return (x + y) / (x - y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
return (x + y) / (x - y);
}
def code(x, y): return (x + y) / (x - y)
function code(x, y) return Float64(Float64(x + y) / Float64(x - y)) end
function tmp = code(x, y) tmp = (x + y) / (x - y); end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x + y}{x - y}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
return (x + y) / (x - y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
return (x + y) / (x - y);
}
def code(x, y): return (x + y) / (x - y)
function code(x, y) return Float64(Float64(x + y) / Float64(x - y)) end
function tmp = code(x, y) tmp = (x + y) / (x - y); end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x + y}{x - y}
\end{array}
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
return (x + y) / (x - y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
return (x + y) / (x - y);
}
def code(x, y): return (x + y) / (x - y)
function code(x, y) return Float64(Float64(x + y) / Float64(x - y)) end
function tmp = code(x, y) tmp = (x + y) / (x - y); end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x + y}{x - y}
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x y)
:precision binary64
(if (or (<= x -1.5e+89)
(not (or (<= x 2e-52) (and (not (<= x 1.06e+43)) (<= x 1.7e+82)))))
(+ 1.0 (* 2.0 (/ y x)))
-1.0))
double code(double x, double y) {
double tmp;
if ((x <= -1.5e+89) || !((x <= 2e-52) || (!(x <= 1.06e+43) && (x <= 1.7e+82)))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-1.5d+89)) .or. (.not. (x <= 2d-52) .or. (.not. (x <= 1.06d+43)) .and. (x <= 1.7d+82))) then
tmp = 1.0d0 + (2.0d0 * (y / x))
else
tmp = -1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -1.5e+89) || !((x <= 2e-52) || (!(x <= 1.06e+43) && (x <= 1.7e+82)))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -1.5e+89) or not ((x <= 2e-52) or (not (x <= 1.06e+43) and (x <= 1.7e+82))): tmp = 1.0 + (2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -1.5e+89) || !((x <= 2e-52) || (!(x <= 1.06e+43) && (x <= 1.7e+82)))) tmp = Float64(1.0 + Float64(2.0 * Float64(y / x))); else tmp = -1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -1.5e+89) || ~(((x <= 2e-52) || (~((x <= 1.06e+43)) && (x <= 1.7e+82))))) tmp = 1.0 + (2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -1.5e+89], N[Not[Or[LessEqual[x, 2e-52], And[N[Not[LessEqual[x, 1.06e+43]], $MachinePrecision], LessEqual[x, 1.7e+82]]]], $MachinePrecision]], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.5 \cdot 10^{+89} \lor \neg \left(x \leq 2 \cdot 10^{-52} \lor \neg \left(x \leq 1.06 \cdot 10^{+43}\right) \land x \leq 1.7 \cdot 10^{+82}\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if x < -1.50000000000000006e89 or 2e-52 < x < 1.06000000000000006e43 or 1.69999999999999997e82 < x Initial program 100.0%
Taylor expanded in y around 0 82.2%
if -1.50000000000000006e89 < x < 2e-52 or 1.06000000000000006e43 < x < 1.69999999999999997e82Initial program 99.9%
Taylor expanded in x around 0 80.8%
Final simplification81.4%
(FPCore (x y)
:precision binary64
(if (or (<= x -1.1e+89)
(not (or (<= x 1.05e-50) (and (not (<= x 2.8e+41)) (<= x 2.15e+83)))))
(+ 1.0 (* 2.0 (/ y x)))
(+ (* -2.0 (/ x y)) -1.0)))
double code(double x, double y) {
double tmp;
if ((x <= -1.1e+89) || !((x <= 1.05e-50) || (!(x <= 2.8e+41) && (x <= 2.15e+83)))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = (-2.0 * (x / y)) + -1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-1.1d+89)) .or. (.not. (x <= 1.05d-50) .or. (.not. (x <= 2.8d+41)) .and. (x <= 2.15d+83))) then
tmp = 1.0d0 + (2.0d0 * (y / x))
else
tmp = ((-2.0d0) * (x / y)) + (-1.0d0)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -1.1e+89) || !((x <= 1.05e-50) || (!(x <= 2.8e+41) && (x <= 2.15e+83)))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = (-2.0 * (x / y)) + -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -1.1e+89) or not ((x <= 1.05e-50) or (not (x <= 2.8e+41) and (x <= 2.15e+83))): tmp = 1.0 + (2.0 * (y / x)) else: tmp = (-2.0 * (x / y)) + -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -1.1e+89) || !((x <= 1.05e-50) || (!(x <= 2.8e+41) && (x <= 2.15e+83)))) tmp = Float64(1.0 + Float64(2.0 * Float64(y / x))); else tmp = Float64(Float64(-2.0 * Float64(x / y)) + -1.0); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -1.1e+89) || ~(((x <= 1.05e-50) || (~((x <= 2.8e+41)) && (x <= 2.15e+83))))) tmp = 1.0 + (2.0 * (y / x)); else tmp = (-2.0 * (x / y)) + -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -1.1e+89], N[Not[Or[LessEqual[x, 1.05e-50], And[N[Not[LessEqual[x, 2.8e+41]], $MachinePrecision], LessEqual[x, 2.15e+83]]]], $MachinePrecision]], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * N[(x / y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.1 \cdot 10^{+89} \lor \neg \left(x \leq 1.05 \cdot 10^{-50} \lor \neg \left(x \leq 2.8 \cdot 10^{+41}\right) \land x \leq 2.15 \cdot 10^{+83}\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{x}{y} + -1\\
\end{array}
\end{array}
if x < -1.1e89 or 1.05e-50 < x < 2.7999999999999999e41 or 2.15e83 < x Initial program 100.0%
Taylor expanded in y around 0 82.2%
if -1.1e89 < x < 1.05e-50 or 2.7999999999999999e41 < x < 2.15e83Initial program 99.9%
Taylor expanded in x around 0 82.5%
Final simplification82.4%
(FPCore (x y) :precision binary64 (if (<= x -5.7e+88) 1.0 (if (<= x 6e-50) -1.0 (if (<= x 1.96e+43) 1.0 (if (<= x 1e+77) -1.0 1.0)))))
double code(double x, double y) {
double tmp;
if (x <= -5.7e+88) {
tmp = 1.0;
} else if (x <= 6e-50) {
tmp = -1.0;
} else if (x <= 1.96e+43) {
tmp = 1.0;
} else if (x <= 1e+77) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-5.7d+88)) then
tmp = 1.0d0
else if (x <= 6d-50) then
tmp = -1.0d0
else if (x <= 1.96d+43) then
tmp = 1.0d0
else if (x <= 1d+77) then
tmp = -1.0d0
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -5.7e+88) {
tmp = 1.0;
} else if (x <= 6e-50) {
tmp = -1.0;
} else if (x <= 1.96e+43) {
tmp = 1.0;
} else if (x <= 1e+77) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -5.7e+88: tmp = 1.0 elif x <= 6e-50: tmp = -1.0 elif x <= 1.96e+43: tmp = 1.0 elif x <= 1e+77: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -5.7e+88) tmp = 1.0; elseif (x <= 6e-50) tmp = -1.0; elseif (x <= 1.96e+43) tmp = 1.0; elseif (x <= 1e+77) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -5.7e+88) tmp = 1.0; elseif (x <= 6e-50) tmp = -1.0; elseif (x <= 1.96e+43) tmp = 1.0; elseif (x <= 1e+77) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -5.7e+88], 1.0, If[LessEqual[x, 6e-50], -1.0, If[LessEqual[x, 1.96e+43], 1.0, If[LessEqual[x, 1e+77], -1.0, 1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -5.7 \cdot 10^{+88}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 6 \cdot 10^{-50}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \leq 1.96 \cdot 10^{+43}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 10^{+77}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -5.70000000000000021e88 or 5.99999999999999981e-50 < x < 1.9600000000000001e43 or 9.99999999999999983e76 < x Initial program 100.0%
Taylor expanded in x around inf 80.8%
if -5.70000000000000021e88 < x < 5.99999999999999981e-50 or 1.9600000000000001e43 < x < 9.99999999999999983e76Initial program 99.9%
Taylor expanded in x around 0 81.2%
Final simplification81.1%
(FPCore (x y) :precision binary64 -1.0)
double code(double x, double y) {
return -1.0;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -1.0d0
end function
public static double code(double x, double y) {
return -1.0;
}
def code(x, y): return -1.0
function code(x, y) return -1.0 end
function tmp = code(x, y) tmp = -1.0; end
code[x_, y_] := -1.0
\begin{array}{l}
\\
-1
\end{array}
Initial program 100.0%
Taylor expanded in x around 0 55.9%
Final simplification55.9%
(FPCore (x y) :precision binary64 (/ 1.0 (- (/ x (+ x y)) (/ y (+ x y)))))
double code(double x, double y) {
return 1.0 / ((x / (x + y)) - (y / (x + y)));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 / ((x / (x + y)) - (y / (x + y)))
end function
public static double code(double x, double y) {
return 1.0 / ((x / (x + y)) - (y / (x + y)));
}
def code(x, y): return 1.0 / ((x / (x + y)) - (y / (x + y)))
function code(x, y) return Float64(1.0 / Float64(Float64(x / Float64(x + y)) - Float64(y / Float64(x + y)))) end
function tmp = code(x, y) tmp = 1.0 / ((x / (x + y)) - (y / (x + y))); end
code[x_, y_] := N[(1.0 / N[(N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision] - N[(y / N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{x}{x + y} - \frac{y}{x + y}}
\end{array}
herbie shell --seed 2024066
(FPCore (x y)
:name "Linear.Projection:perspective from linear-1.19.1.3, A"
:precision binary64
:alt
(/ 1.0 (- (/ x (+ x y)) (/ y (+ x y))))
(/ (+ x y) (- x y)))