
(FPCore (f n) :precision binary64 (/ (- (+ f n)) (- f n)))
double code(double f, double n) {
return -(f + n) / (f - n);
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = -(f + n) / (f - n)
end function
public static double code(double f, double n) {
return -(f + n) / (f - n);
}
def code(f, n): return -(f + n) / (f - n)
function code(f, n) return Float64(Float64(-Float64(f + n)) / Float64(f - n)) end
function tmp = code(f, n) tmp = -(f + n) / (f - n); end
code[f_, n_] := N[((-N[(f + n), $MachinePrecision]) / N[(f - n), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-\left(f + n\right)}{f - n}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (f n) :precision binary64 (/ (- (+ f n)) (- f n)))
double code(double f, double n) {
return -(f + n) / (f - n);
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = -(f + n) / (f - n)
end function
public static double code(double f, double n) {
return -(f + n) / (f - n);
}
def code(f, n): return -(f + n) / (f - n)
function code(f, n) return Float64(Float64(-Float64(f + n)) / Float64(f - n)) end
function tmp = code(f, n) tmp = -(f + n) / (f - n); end
code[f_, n_] := N[((-N[(f + n), $MachinePrecision]) / N[(f - n), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-\left(f + n\right)}{f - n}
\end{array}
(FPCore (f n) :precision binary64 (/ 1.0 (- (/ n (+ n f)) (/ f (+ n f)))))
double code(double f, double n) {
return 1.0 / ((n / (n + f)) - (f / (n + f)));
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = 1.0d0 / ((n / (n + f)) - (f / (n + f)))
end function
public static double code(double f, double n) {
return 1.0 / ((n / (n + f)) - (f / (n + f)));
}
def code(f, n): return 1.0 / ((n / (n + f)) - (f / (n + f)))
function code(f, n) return Float64(1.0 / Float64(Float64(n / Float64(n + f)) - Float64(f / Float64(n + f)))) end
function tmp = code(f, n) tmp = 1.0 / ((n / (n + f)) - (f / (n + f))); end
code[f_, n_] := N[(1.0 / N[(N[(n / N[(n + f), $MachinePrecision]), $MachinePrecision] - N[(f / N[(n + f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{n}{n + f} - \frac{f}{n + f}}
\end{array}
Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
unpow-1100.0%
+-commutative100.0%
Applied egg-rr100.0%
div-sub100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n)
:precision binary64
(if (or (<= n -1.32e+82)
(not
(or (<= n -1.05e+31) (and (not (<= n -4.3e-44)) (<= n 2.15e-54)))))
(+ 1.0 (* 2.0 (/ f n)))
-1.0))
double code(double f, double n) {
double tmp;
if ((n <= -1.32e+82) || !((n <= -1.05e+31) || (!(n <= -4.3e-44) && (n <= 2.15e-54)))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((n <= (-1.32d+82)) .or. (.not. (n <= (-1.05d+31)) .or. (.not. (n <= (-4.3d-44))) .and. (n <= 2.15d-54))) then
tmp = 1.0d0 + (2.0d0 * (f / n))
else
tmp = -1.0d0
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((n <= -1.32e+82) || !((n <= -1.05e+31) || (!(n <= -4.3e-44) && (n <= 2.15e-54)))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -1.32e+82) or not ((n <= -1.05e+31) or (not (n <= -4.3e-44) and (n <= 2.15e-54))): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if ((n <= -1.32e+82) || !((n <= -1.05e+31) || (!(n <= -4.3e-44) && (n <= 2.15e-54)))) tmp = Float64(1.0 + Float64(2.0 * Float64(f / n))); else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((n <= -1.32e+82) || ~(((n <= -1.05e+31) || (~((n <= -4.3e-44)) && (n <= 2.15e-54))))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -1.32e+82], N[Not[Or[LessEqual[n, -1.05e+31], And[N[Not[LessEqual[n, -4.3e-44]], $MachinePrecision], LessEqual[n, 2.15e-54]]]], $MachinePrecision]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -1.32 \cdot 10^{+82} \lor \neg \left(n \leq -1.05 \cdot 10^{+31} \lor \neg \left(n \leq -4.3 \cdot 10^{-44}\right) \land n \leq 2.15 \cdot 10^{-54}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if n < -1.32e82 or -1.04999999999999989e31 < n < -4.30000000000000013e-44 or 2.15e-54 < n Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around 0 83.7%
if -1.32e82 < n < -1.04999999999999989e31 or -4.30000000000000013e-44 < n < 2.15e-54Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around inf 83.4%
Final simplification83.6%
(FPCore (f n)
:precision binary64
(if (or (<= n -5.8e+82)
(and (not (<= n -5.2e+27))
(or (<= n -5.3e-34) (not (<= n 2.55e-66)))))
(+ 1.0 (* 2.0 (/ f n)))
(+ (* -2.0 (/ n f)) -1.0)))
double code(double f, double n) {
double tmp;
if ((n <= -5.8e+82) || (!(n <= -5.2e+27) && ((n <= -5.3e-34) || !(n <= 2.55e-66)))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = (-2.0 * (n / f)) + -1.0;
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((n <= (-5.8d+82)) .or. (.not. (n <= (-5.2d+27))) .and. (n <= (-5.3d-34)) .or. (.not. (n <= 2.55d-66))) then
tmp = 1.0d0 + (2.0d0 * (f / n))
else
tmp = ((-2.0d0) * (n / f)) + (-1.0d0)
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((n <= -5.8e+82) || (!(n <= -5.2e+27) && ((n <= -5.3e-34) || !(n <= 2.55e-66)))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = (-2.0 * (n / f)) + -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -5.8e+82) or (not (n <= -5.2e+27) and ((n <= -5.3e-34) or not (n <= 2.55e-66))): tmp = 1.0 + (2.0 * (f / n)) else: tmp = (-2.0 * (n / f)) + -1.0 return tmp
function code(f, n) tmp = 0.0 if ((n <= -5.8e+82) || (!(n <= -5.2e+27) && ((n <= -5.3e-34) || !(n <= 2.55e-66)))) tmp = Float64(1.0 + Float64(2.0 * Float64(f / n))); else tmp = Float64(Float64(-2.0 * Float64(n / f)) + -1.0); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((n <= -5.8e+82) || (~((n <= -5.2e+27)) && ((n <= -5.3e-34) || ~((n <= 2.55e-66))))) tmp = 1.0 + (2.0 * (f / n)); else tmp = (-2.0 * (n / f)) + -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -5.8e+82], And[N[Not[LessEqual[n, -5.2e+27]], $MachinePrecision], Or[LessEqual[n, -5.3e-34], N[Not[LessEqual[n, 2.55e-66]], $MachinePrecision]]]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * N[(n / f), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -5.8 \cdot 10^{+82} \lor \neg \left(n \leq -5.2 \cdot 10^{+27}\right) \land \left(n \leq -5.3 \cdot 10^{-34} \lor \neg \left(n \leq 2.55 \cdot 10^{-66}\right)\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\end{array}
\end{array}
if n < -5.8000000000000003e82 or -5.20000000000000018e27 < n < -5.2999999999999997e-34 or 2.55000000000000011e-66 < n Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around 0 83.7%
if -5.8000000000000003e82 < n < -5.20000000000000018e27 or -5.2999999999999997e-34 < n < 2.55000000000000011e-66Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in n around 0 85.0%
Final simplification84.3%
(FPCore (f n) :precision binary64 (+ (/ n (- n f)) (/ f (- n f))))
double code(double f, double n) {
return (n / (n - f)) + (f / (n - f));
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = (n / (n - f)) + (f / (n - f))
end function
public static double code(double f, double n) {
return (n / (n - f)) + (f / (n - f));
}
def code(f, n): return (n / (n - f)) + (f / (n - f))
function code(f, n) return Float64(Float64(n / Float64(n - f)) + Float64(f / Float64(n - f))) end
function tmp = code(f, n) tmp = (n / (n - f)) + (f / (n - f)); end
code[f_, n_] := N[(N[(n / N[(n - f), $MachinePrecision]), $MachinePrecision] + N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{n}{n - f} + \frac{f}{n - f}
\end{array}
Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
unpow-1100.0%
associate-/r/99.8%
+-commutative99.8%
distribute-rgt-in99.8%
un-div-inv99.9%
un-div-inv100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n)
:precision binary64
(if (<= n -1.45e+82)
1.0
(if (<= n -1e+31)
-1.0
(if (<= n -5.5e-34) 1.0 (if (<= n 2.65e-60) -1.0 1.0)))))
double code(double f, double n) {
double tmp;
if (n <= -1.45e+82) {
tmp = 1.0;
} else if (n <= -1e+31) {
tmp = -1.0;
} else if (n <= -5.5e-34) {
tmp = 1.0;
} else if (n <= 2.65e-60) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if (n <= (-1.45d+82)) then
tmp = 1.0d0
else if (n <= (-1d+31)) then
tmp = -1.0d0
else if (n <= (-5.5d-34)) then
tmp = 1.0d0
else if (n <= 2.65d-60) then
tmp = -1.0d0
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if (n <= -1.45e+82) {
tmp = 1.0;
} else if (n <= -1e+31) {
tmp = -1.0;
} else if (n <= -5.5e-34) {
tmp = 1.0;
} else if (n <= 2.65e-60) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if n <= -1.45e+82: tmp = 1.0 elif n <= -1e+31: tmp = -1.0 elif n <= -5.5e-34: tmp = 1.0 elif n <= 2.65e-60: tmp = -1.0 else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if (n <= -1.45e+82) tmp = 1.0; elseif (n <= -1e+31) tmp = -1.0; elseif (n <= -5.5e-34) tmp = 1.0; elseif (n <= 2.65e-60) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (n <= -1.45e+82) tmp = 1.0; elseif (n <= -1e+31) tmp = -1.0; elseif (n <= -5.5e-34) tmp = 1.0; elseif (n <= 2.65e-60) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[n, -1.45e+82], 1.0, If[LessEqual[n, -1e+31], -1.0, If[LessEqual[n, -5.5e-34], 1.0, If[LessEqual[n, 2.65e-60], -1.0, 1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -1.45 \cdot 10^{+82}:\\
\;\;\;\;1\\
\mathbf{elif}\;n \leq -1 \cdot 10^{+31}:\\
\;\;\;\;-1\\
\mathbf{elif}\;n \leq -5.5 \cdot 10^{-34}:\\
\;\;\;\;1\\
\mathbf{elif}\;n \leq 2.65 \cdot 10^{-60}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if n < -1.4500000000000001e82 or -9.9999999999999996e30 < n < -5.50000000000000014e-34 or 2.65e-60 < n Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around 0 82.8%
if -1.4500000000000001e82 < n < -9.9999999999999996e30 or -5.50000000000000014e-34 < n < 2.65e-60Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around inf 83.4%
Final simplification83.1%
(FPCore (f n) :precision binary64 (/ 1.0 (/ (- n f) (+ n f))))
double code(double f, double n) {
return 1.0 / ((n - f) / (n + f));
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = 1.0d0 / ((n - f) / (n + f))
end function
public static double code(double f, double n) {
return 1.0 / ((n - f) / (n + f));
}
def code(f, n): return 1.0 / ((n - f) / (n + f))
function code(f, n) return Float64(1.0 / Float64(Float64(n - f) / Float64(n + f))) end
function tmp = code(f, n) tmp = 1.0 / ((n - f) / (n + f)); end
code[f_, n_] := N[(1.0 / N[(N[(n - f), $MachinePrecision] / N[(n + f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{n - f}{n + f}}
\end{array}
Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
unpow-1100.0%
+-commutative100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (/ (+ n f) (- n f)))
double code(double f, double n) {
return (n + f) / (n - f);
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = (n + f) / (n - f)
end function
public static double code(double f, double n) {
return (n + f) / (n - f);
}
def code(f, n): return (n + f) / (n - f)
function code(f, n) return Float64(Float64(n + f) / Float64(n - f)) end
function tmp = code(f, n) tmp = (n + f) / (n - f); end
code[f_, n_] := N[(N[(n + f), $MachinePrecision] / N[(n - f), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{n + f}{n - f}
\end{array}
Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Final simplification99.9%
(FPCore (f n) :precision binary64 -1.0)
double code(double f, double n) {
return -1.0;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = -1.0d0
end function
public static double code(double f, double n) {
return -1.0;
}
def code(f, n): return -1.0
function code(f, n) return -1.0 end
function tmp = code(f, n) tmp = -1.0; end
code[f_, n_] := -1.0
\begin{array}{l}
\\
-1
\end{array}
Initial program 99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
div-sub99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/l*99.9%
*-commutative99.9%
neg-mul-199.9%
div-sub99.9%
unsub-neg99.9%
remove-double-neg99.9%
+-commutative99.9%
sub-neg99.9%
metadata-eval99.9%
/-rgt-identity99.9%
Simplified99.9%
Taylor expanded in f around inf 47.8%
Final simplification47.8%
herbie shell --seed 2023187
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))