
(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 7 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 (/ 1.0 (log1p (expm1 (/ (- x y) (+ x y))))))
double code(double x, double y) {
return 1.0 / log1p(expm1(((x - y) / (x + y))));
}
public static double code(double x, double y) {
return 1.0 / Math.log1p(Math.expm1(((x - y) / (x + y))));
}
def code(x, y): return 1.0 / math.log1p(math.expm1(((x - y) / (x + y))))
function code(x, y) return Float64(1.0 / log1p(expm1(Float64(Float64(x - y) / Float64(x + y))))) end
code[x_, y_] := N[(1.0 / N[Log[1 + N[(Exp[N[(N[(x - y), $MachinePrecision] / N[(x + y), $MachinePrecision]), $MachinePrecision]] - 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\mathsf{log1p}\left(\mathsf{expm1}\left(\frac{x - y}{x + y}\right)\right)}
\end{array}
Initial program 99.9%
add-log-exp99.9%
Applied egg-rr99.9%
rem-log-exp99.9%
clear-num99.9%
Applied egg-rr99.9%
log1p-expm1-u99.9%
Applied egg-rr99.9%
Final simplification99.9%
(FPCore (x y)
:precision binary64
(if (or (<= x -3.1e-100)
(and (not (<= x 3e-80))
(or (<= x 2050000000000.0) (not (<= x 1.7e+44)))))
(+ 1.0 (* 2.0 (/ y x)))
-1.0))
double code(double x, double y) {
double tmp;
if ((x <= -3.1e-100) || (!(x <= 3e-80) && ((x <= 2050000000000.0) || !(x <= 1.7e+44)))) {
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 <= (-3.1d-100)) .or. (.not. (x <= 3d-80)) .and. (x <= 2050000000000.0d0) .or. (.not. (x <= 1.7d+44))) 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 <= -3.1e-100) || (!(x <= 3e-80) && ((x <= 2050000000000.0) || !(x <= 1.7e+44)))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -3.1e-100) or (not (x <= 3e-80) and ((x <= 2050000000000.0) or not (x <= 1.7e+44))): tmp = 1.0 + (2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -3.1e-100) || (!(x <= 3e-80) && ((x <= 2050000000000.0) || !(x <= 1.7e+44)))) 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 <= -3.1e-100) || (~((x <= 3e-80)) && ((x <= 2050000000000.0) || ~((x <= 1.7e+44))))) tmp = 1.0 + (2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -3.1e-100], And[N[Not[LessEqual[x, 3e-80]], $MachinePrecision], Or[LessEqual[x, 2050000000000.0], N[Not[LessEqual[x, 1.7e+44]], $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 -3.1 \cdot 10^{-100} \lor \neg \left(x \leq 3 \cdot 10^{-80}\right) \land \left(x \leq 2050000000000 \lor \neg \left(x \leq 1.7 \cdot 10^{+44}\right)\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if x < -3.0999999999999999e-100 or 3.00000000000000007e-80 < x < 2.05e12 or 1.7e44 < x Initial program 99.9%
Taylor expanded in y around 0 75.5%
if -3.0999999999999999e-100 < x < 3.00000000000000007e-80 or 2.05e12 < x < 1.7e44Initial program 99.9%
Taylor expanded in x around 0 85.0%
Final simplification79.7%
(FPCore (x y)
:precision binary64
(if (or (<= x -1.6e-99)
(not (or (<= x 3e-80) (and (not (<= x 1.35e+17)) (<= x 6.4e+45)))))
(+ 1.0 (* 2.0 (/ y x)))
(+ (* -2.0 (/ x y)) -1.0)))
double code(double x, double y) {
double tmp;
if ((x <= -1.6e-99) || !((x <= 3e-80) || (!(x <= 1.35e+17) && (x <= 6.4e+45)))) {
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 <= (-1.6d-99)) .or. (.not. (x <= 3d-80) .or. (.not. (x <= 1.35d+17)) .and. (x <= 6.4d+45))) 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 <= -1.6e-99) || !((x <= 3e-80) || (!(x <= 1.35e+17) && (x <= 6.4e+45)))) {
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 <= -1.6e-99) or not ((x <= 3e-80) or (not (x <= 1.35e+17) and (x <= 6.4e+45))): 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 <= -1.6e-99) || !((x <= 3e-80) || (!(x <= 1.35e+17) && (x <= 6.4e+45)))) 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 <= -1.6e-99) || ~(((x <= 3e-80) || (~((x <= 1.35e+17)) && (x <= 6.4e+45))))) 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, -1.6e-99], N[Not[Or[LessEqual[x, 3e-80], And[N[Not[LessEqual[x, 1.35e+17]], $MachinePrecision], LessEqual[x, 6.4e+45]]]], $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 -1.6 \cdot 10^{-99} \lor \neg \left(x \leq 3 \cdot 10^{-80} \lor \neg \left(x \leq 1.35 \cdot 10^{+17}\right) \land x \leq 6.4 \cdot 10^{+45}\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{x}{y} + -1\\
\end{array}
\end{array}
if x < -1.6e-99 or 3.00000000000000007e-80 < x < 1.35e17 or 6.4000000000000006e45 < x Initial program 99.9%
Taylor expanded in y around 0 75.5%
if -1.6e-99 < x < 3.00000000000000007e-80 or 1.35e17 < x < 6.4000000000000006e45Initial program 99.9%
Taylor expanded in x around 0 86.2%
Final simplification80.2%
(FPCore (x y)
:precision binary64
(if (<= x -1.6e-99)
1.0
(if (<= x 1e-84)
-1.0
(if (<= x 20000000000.0) 1.0 (if (<= x 2.3e+44) -1.0 1.0)))))
double code(double x, double y) {
double tmp;
if (x <= -1.6e-99) {
tmp = 1.0;
} else if (x <= 1e-84) {
tmp = -1.0;
} else if (x <= 20000000000.0) {
tmp = 1.0;
} else if (x <= 2.3e+44) {
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 <= (-1.6d-99)) then
tmp = 1.0d0
else if (x <= 1d-84) then
tmp = -1.0d0
else if (x <= 20000000000.0d0) then
tmp = 1.0d0
else if (x <= 2.3d+44) 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 <= -1.6e-99) {
tmp = 1.0;
} else if (x <= 1e-84) {
tmp = -1.0;
} else if (x <= 20000000000.0) {
tmp = 1.0;
} else if (x <= 2.3e+44) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.6e-99: tmp = 1.0 elif x <= 1e-84: tmp = -1.0 elif x <= 20000000000.0: tmp = 1.0 elif x <= 2.3e+44: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -1.6e-99) tmp = 1.0; elseif (x <= 1e-84) tmp = -1.0; elseif (x <= 20000000000.0) tmp = 1.0; elseif (x <= 2.3e+44) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.6e-99) tmp = 1.0; elseif (x <= 1e-84) tmp = -1.0; elseif (x <= 20000000000.0) tmp = 1.0; elseif (x <= 2.3e+44) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.6e-99], 1.0, If[LessEqual[x, 1e-84], -1.0, If[LessEqual[x, 20000000000.0], 1.0, If[LessEqual[x, 2.3e+44], -1.0, 1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.6 \cdot 10^{-99}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 10^{-84}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \leq 20000000000:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 2.3 \cdot 10^{+44}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1.6e-99 or 1e-84 < x < 2e10 or 2.30000000000000004e44 < x Initial program 99.9%
Taylor expanded in x around inf 74.1%
if -1.6e-99 < x < 1e-84 or 2e10 < x < 2.30000000000000004e44Initial program 99.9%
Taylor expanded in x around 0 85.0%
Final simplification78.9%
(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}
Initial program 99.9%
add-log-exp99.9%
Applied egg-rr99.9%
rem-log-exp99.9%
clear-num99.9%
Applied egg-rr99.9%
div-sub99.9%
Applied egg-rr99.9%
Final simplification99.9%
(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 99.9%
Final simplification99.9%
(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 99.9%
Taylor expanded in x around 0 50.0%
Final simplification50.0%
(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 2024115
(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)))