
(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 6 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 (/ 1.0 (/ (+ n f) (- n f)))))
double code(double f, double n) {
return 1.0 / (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 / (1.0d0 / ((n + f) / (n - f)))
end function
public static double code(double f, double n) {
return 1.0 / (1.0 / ((n + f) / (n - f)));
}
def code(f, n): return 1.0 / (1.0 / ((n + f) / (n - f)))
function code(f, n) return Float64(1.0 / Float64(1.0 / Float64(Float64(n + f) / Float64(n - f)))) end
function tmp = code(f, n) tmp = 1.0 / (1.0 / ((n + f) / (n - f))); end
code[f_, n_] := N[(1.0 / N[(1.0 / N[(N[(n + f), $MachinePrecision] / N[(n - f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{1}{\frac{n + f}{n - f}}}
\end{array}
Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
clear-num100.0%
associate-/r/99.8%
Applied egg-rr99.8%
associate-*l/100.0%
add-sqr-sqrt46.8%
times-frac46.8%
clear-num46.9%
div-inv46.9%
clear-num46.8%
clear-num46.8%
div-inv46.8%
clear-num46.7%
times-frac46.7%
add-sqr-sqrt100.0%
*-un-lft-identity100.0%
+-commutative100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (or (<= n -2.2e-71) (not (<= n 6e+50))) (+ 1.0 (* 2.0 (/ f n))) -1.0))
double code(double f, double n) {
double tmp;
if ((n <= -2.2e-71) || !(n <= 6e+50)) {
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 <= (-2.2d-71)) .or. (.not. (n <= 6d+50))) 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 <= -2.2e-71) || !(n <= 6e+50)) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -2.2e-71) or not (n <= 6e+50): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if ((n <= -2.2e-71) || !(n <= 6e+50)) 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 <= -2.2e-71) || ~((n <= 6e+50))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -2.2e-71], N[Not[LessEqual[n, 6e+50]], $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 -2.2 \cdot 10^{-71} \lor \neg \left(n \leq 6 \cdot 10^{+50}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if n < -2.19999999999999997e-71 or 5.9999999999999996e50 < n Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around 0 80.1%
if -2.19999999999999997e-71 < n < 5.9999999999999996e50Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around inf 77.0%
Final simplification78.6%
(FPCore (f n) :precision binary64 (if (or (<= n -2.05e-39) (not (<= n 8.2e+49))) (+ 1.0 (* 2.0 (/ f n))) (+ (* -2.0 (/ n f)) -1.0)))
double code(double f, double n) {
double tmp;
if ((n <= -2.05e-39) || !(n <= 8.2e+49)) {
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 <= (-2.05d-39)) .or. (.not. (n <= 8.2d+49))) 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 <= -2.05e-39) || !(n <= 8.2e+49)) {
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 <= -2.05e-39) or not (n <= 8.2e+49): 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 <= -2.05e-39) || !(n <= 8.2e+49)) 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 <= -2.05e-39) || ~((n <= 8.2e+49))) 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, -2.05e-39], N[Not[LessEqual[n, 8.2e+49]], $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 -2.05 \cdot 10^{-39} \lor \neg \left(n \leq 8.2 \cdot 10^{+49}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\end{array}
\end{array}
if n < -2.05e-39 or 8.2e49 < n Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around 0 82.1%
if -2.05e-39 < n < 8.2e49Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in n around 0 76.4%
Final simplification79.1%
(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 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (<= n -1.86e-93) 1.0 (if (<= n 5e+49) -1.0 1.0)))
double code(double f, double n) {
double tmp;
if (n <= -1.86e-93) {
tmp = 1.0;
} else if (n <= 5e+49) {
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 <= (-1.86d-93)) then
tmp = 1.0d0
else if (n <= 5d+49) 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 <= -1.86e-93) {
tmp = 1.0;
} else if (n <= 5e+49) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if n <= -1.86e-93: tmp = 1.0 elif n <= 5e+49: tmp = -1.0 else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if (n <= -1.86e-93) tmp = 1.0; elseif (n <= 5e+49) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (n <= -1.86e-93) tmp = 1.0; elseif (n <= 5e+49) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[n, -1.86e-93], 1.0, If[LessEqual[n, 5e+49], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -1.86 \cdot 10^{-93}:\\
\;\;\;\;1\\
\mathbf{elif}\;n \leq 5 \cdot 10^{+49}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if n < -1.8600000000000001e-93 or 5.0000000000000004e49 < n Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around 0 78.5%
if -1.8600000000000001e-93 < n < 5.0000000000000004e49Initial program 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around inf 77.8%
Final simplification78.1%
(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 100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
div-sub100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/l*100.0%
*-commutative100.0%
neg-mul-1100.0%
div-sub100.0%
unsub-neg100.0%
remove-double-neg100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
/-rgt-identity100.0%
Simplified100.0%
Taylor expanded in f around inf 49.0%
Final simplification49.0%
herbie shell --seed 2023217
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))