
(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 (+ (exp (log1p (/ (+ x y) (- x y)))) -1.0))
double code(double x, double y) {
return exp(log1p(((x + y) / (x - y)))) + -1.0;
}
public static double code(double x, double y) {
return Math.exp(Math.log1p(((x + y) / (x - y)))) + -1.0;
}
def code(x, y): return math.exp(math.log1p(((x + y) / (x - y)))) + -1.0
function code(x, y) return Float64(exp(log1p(Float64(Float64(x + y) / Float64(x - y)))) + -1.0) end
code[x_, y_] := N[(N[Exp[N[Log[1 + N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] + -1.0), $MachinePrecision]
\begin{array}{l}
\\
e^{\mathsf{log1p}\left(\frac{x + y}{x - y}\right)} + -1
\end{array}
Initial program 99.9%
expm1-log1p-u100.0%
expm1-udef100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (x y)
:precision binary64
(if (or (<= y -34000000.0)
(not (or (<= y 4e+15) (and (not (<= y 1.35e+141)) (<= y 1.2e+199)))))
(+ (* -2.0 (/ x y)) -1.0)
(+ 1.0 (* 2.0 (/ y x)))))
double code(double x, double y) {
double tmp;
if ((y <= -34000000.0) || !((y <= 4e+15) || (!(y <= 1.35e+141) && (y <= 1.2e+199)))) {
tmp = (-2.0 * (x / y)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (y / x));
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((y <= (-34000000.0d0)) .or. (.not. (y <= 4d+15) .or. (.not. (y <= 1.35d+141)) .and. (y <= 1.2d+199))) then
tmp = ((-2.0d0) * (x / y)) + (-1.0d0)
else
tmp = 1.0d0 + (2.0d0 * (y / x))
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -34000000.0) || !((y <= 4e+15) || (!(y <= 1.35e+141) && (y <= 1.2e+199)))) {
tmp = (-2.0 * (x / y)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (y / x));
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -34000000.0) or not ((y <= 4e+15) or (not (y <= 1.35e+141) and (y <= 1.2e+199))): tmp = (-2.0 * (x / y)) + -1.0 else: tmp = 1.0 + (2.0 * (y / x)) return tmp
function code(x, y) tmp = 0.0 if ((y <= -34000000.0) || !((y <= 4e+15) || (!(y <= 1.35e+141) && (y <= 1.2e+199)))) tmp = Float64(Float64(-2.0 * Float64(x / y)) + -1.0); else tmp = Float64(1.0 + Float64(2.0 * Float64(y / x))); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -34000000.0) || ~(((y <= 4e+15) || (~((y <= 1.35e+141)) && (y <= 1.2e+199))))) tmp = (-2.0 * (x / y)) + -1.0; else tmp = 1.0 + (2.0 * (y / x)); end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -34000000.0], N[Not[Or[LessEqual[y, 4e+15], And[N[Not[LessEqual[y, 1.35e+141]], $MachinePrecision], LessEqual[y, 1.2e+199]]]], $MachinePrecision]], N[(N[(-2.0 * N[(x / y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -34000000 \lor \neg \left(y \leq 4 \cdot 10^{+15} \lor \neg \left(y \leq 1.35 \cdot 10^{+141}\right) \land y \leq 1.2 \cdot 10^{+199}\right):\\
\;\;\;\;-2 \cdot \frac{x}{y} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\end{array}
\end{array}
if y < -3.4e7 or 4e15 < y < 1.35e141 or 1.20000000000000007e199 < y Initial program 99.9%
Taylor expanded in x around 0 85.6%
if -3.4e7 < y < 4e15 or 1.35e141 < y < 1.20000000000000007e199Initial program 100.0%
Taylor expanded in y around 0 82.3%
Final simplification83.8%
(FPCore (x y)
:precision binary64
(if (<= y -42000.0)
-1.0
(if (or (<= y 2500000000000.0) (and (not (<= y 1.4e+142)) (<= y 1.25e+199)))
(+ 1.0 (* 2.0 (/ y x)))
-1.0)))
double code(double x, double y) {
double tmp;
if (y <= -42000.0) {
tmp = -1.0;
} else if ((y <= 2500000000000.0) || (!(y <= 1.4e+142) && (y <= 1.25e+199))) {
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 (y <= (-42000.0d0)) then
tmp = -1.0d0
else if ((y <= 2500000000000.0d0) .or. (.not. (y <= 1.4d+142)) .and. (y <= 1.25d+199)) 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 (y <= -42000.0) {
tmp = -1.0;
} else if ((y <= 2500000000000.0) || (!(y <= 1.4e+142) && (y <= 1.25e+199))) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -42000.0: tmp = -1.0 elif (y <= 2500000000000.0) or (not (y <= 1.4e+142) and (y <= 1.25e+199)): tmp = 1.0 + (2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -42000.0) tmp = -1.0; elseif ((y <= 2500000000000.0) || (!(y <= 1.4e+142) && (y <= 1.25e+199))) 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 (y <= -42000.0) tmp = -1.0; elseif ((y <= 2500000000000.0) || (~((y <= 1.4e+142)) && (y <= 1.25e+199))) tmp = 1.0 + (2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -42000.0], -1.0, If[Or[LessEqual[y, 2500000000000.0], And[N[Not[LessEqual[y, 1.4e+142]], $MachinePrecision], LessEqual[y, 1.25e+199]]], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -42000:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \leq 2500000000000 \lor \neg \left(y \leq 1.4 \cdot 10^{+142}\right) \land y \leq 1.25 \cdot 10^{+199}:\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if y < -42000 or 2.5e12 < y < 1.4e142 or 1.25e199 < y Initial program 99.9%
Taylor expanded in x around 0 84.7%
if -42000 < y < 2.5e12 or 1.4e142 < y < 1.25e199Initial program 100.0%
Taylor expanded in y around 0 82.3%
Final simplification83.4%
(FPCore (x y)
:precision binary64
(if (<= y -5e+14)
-1.0
(if (<= y 4.4e+16)
1.0
(if (<= y 1.4e+142) -1.0 (if (<= y 1.2e+199) 1.0 -1.0)))))
double code(double x, double y) {
double tmp;
if (y <= -5e+14) {
tmp = -1.0;
} else if (y <= 4.4e+16) {
tmp = 1.0;
} else if (y <= 1.4e+142) {
tmp = -1.0;
} else if (y <= 1.2e+199) {
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 (y <= (-5d+14)) then
tmp = -1.0d0
else if (y <= 4.4d+16) then
tmp = 1.0d0
else if (y <= 1.4d+142) then
tmp = -1.0d0
else if (y <= 1.2d+199) 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 (y <= -5e+14) {
tmp = -1.0;
} else if (y <= 4.4e+16) {
tmp = 1.0;
} else if (y <= 1.4e+142) {
tmp = -1.0;
} else if (y <= 1.2e+199) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -5e+14: tmp = -1.0 elif y <= 4.4e+16: tmp = 1.0 elif y <= 1.4e+142: tmp = -1.0 elif y <= 1.2e+199: tmp = 1.0 else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -5e+14) tmp = -1.0; elseif (y <= 4.4e+16) tmp = 1.0; elseif (y <= 1.4e+142) tmp = -1.0; elseif (y <= 1.2e+199) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -5e+14) tmp = -1.0; elseif (y <= 4.4e+16) tmp = 1.0; elseif (y <= 1.4e+142) tmp = -1.0; elseif (y <= 1.2e+199) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -5e+14], -1.0, If[LessEqual[y, 4.4e+16], 1.0, If[LessEqual[y, 1.4e+142], -1.0, If[LessEqual[y, 1.2e+199], 1.0, -1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -5 \cdot 10^{+14}:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \leq 4.4 \cdot 10^{+16}:\\
\;\;\;\;1\\
\mathbf{elif}\;y \leq 1.4 \cdot 10^{+142}:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \leq 1.2 \cdot 10^{+199}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if y < -5e14 or 4.4e16 < y < 1.4e142 or 1.20000000000000007e199 < y Initial program 99.9%
Taylor expanded in x around 0 84.7%
if -5e14 < y < 4.4e16 or 1.4e142 < y < 1.20000000000000007e199Initial program 100.0%
Taylor expanded in x around inf 81.4%
Final simplification82.9%
(FPCore (x y) :precision binary64 (/ 1.0 (/ (- x y) (+ x y))))
double code(double x, double y) {
return 1.0 / ((x - y) / (x + y));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 / ((x - y) / (x + y))
end function
public static double code(double x, double y) {
return 1.0 / ((x - y) / (x + y));
}
def code(x, y): return 1.0 / ((x - y) / (x + y))
function code(x, y) return Float64(1.0 / Float64(Float64(x - y) / Float64(x + y))) end
function tmp = code(x, y) tmp = 1.0 / ((x - y) / (x + y)); end
code[x_, y_] := N[(1.0 / N[(N[(x - y), $MachinePrecision] / N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{x - y}{x + y}}
\end{array}
Initial program 99.9%
expm1-log1p-u100.0%
expm1-udef100.0%
Applied egg-rr100.0%
expm1-def100.0%
expm1-log1p-u99.9%
clear-num99.9%
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 49.2%
Final simplification49.2%
(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 2023320
(FPCore (x y)
:name "Linear.Projection:perspective from linear-1.19.1.3, A"
:precision binary64
:herbie-target
(/ 1.0 (- (/ x (+ x y)) (/ y (+ x y))))
(/ (+ x y) (- x y)))