
(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 (+ (/ 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%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
add-log-exp100.0%
Applied egg-rr100.0%
*-un-lft-identity100.0%
associate-*l/99.7%
add-log-exp99.7%
+-commutative99.7%
distribute-rgt-in99.7%
un-div-inv99.8%
un-div-inv100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (or (<= n -2.4e-51) (not (<= n 2.8e-74))) (+ 1.0 (* 2.0 (/ f n))) -1.0))
double code(double f, double n) {
double tmp;
if ((n <= -2.4e-51) || !(n <= 2.8e-74)) {
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 <= (-2.4d-51)) .or. (.not. (n <= 2.8d-74))) 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 <= -2.4e-51) || !(n <= 2.8e-74)) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -2.4e-51) or not (n <= 2.8e-74): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if ((n <= -2.4e-51) || !(n <= 2.8e-74)) 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 <= -2.4e-51) || ~((n <= 2.8e-74))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -2.4e-51], N[Not[LessEqual[n, 2.8e-74]], $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 -2.4 \cdot 10^{-51} \lor \neg \left(n \leq 2.8 \cdot 10^{-74}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if n < -2.4e-51 or 2.79999999999999988e-74 < n Initial program 99.9%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 73.3%
if -2.4e-51 < n < 2.79999999999999988e-74Initial program 100.0%
/-rgt-identity100.0%
metadata-eval100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/r*100.0%
neg-mul-1100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around inf 82.3%
Final simplification77.0%
(FPCore (f n) :precision binary64 (if (or (<= n -2.4e-51) (not (<= n 8.5e-75))) (+ 1.0 (* 2.0 (/ f n))) (+ (* -2.0 (/ n f)) -1.0)))
double code(double f, double n) {
double tmp;
if ((n <= -2.4e-51) || !(n <= 8.5e-75)) {
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 <= (-2.4d-51)) .or. (.not. (n <= 8.5d-75))) 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 <= -2.4e-51) || !(n <= 8.5e-75)) {
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 <= -2.4e-51) or not (n <= 8.5e-75): 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 <= -2.4e-51) || !(n <= 8.5e-75)) 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 <= -2.4e-51) || ~((n <= 8.5e-75))) 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, -2.4e-51], N[Not[LessEqual[n, 8.5e-75]], $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 -2.4 \cdot 10^{-51} \lor \neg \left(n \leq 8.5 \cdot 10^{-75}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\end{array}
\end{array}
if n < -2.4e-51 or 8.5000000000000001e-75 < n Initial program 99.9%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 73.3%
if -2.4e-51 < n < 8.5000000000000001e-75Initial program 100.0%
/-rgt-identity100.0%
metadata-eval100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/r*100.0%
neg-mul-1100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in n around 0 83.4%
Final simplification77.5%
(FPCore (f n) :precision binary64 (if (<= n -1.2e-52) 1.0 (if (<= n 3e-74) -1.0 1.0)))
double code(double f, double n) {
double tmp;
if (n <= -1.2e-52) {
tmp = 1.0;
} else if (n <= 3e-74) {
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 <= (-1.2d-52)) then
tmp = 1.0d0
else if (n <= 3d-74) 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 <= -1.2e-52) {
tmp = 1.0;
} else if (n <= 3e-74) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if n <= -1.2e-52: tmp = 1.0 elif n <= 3e-74: tmp = -1.0 else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if (n <= -1.2e-52) tmp = 1.0; elseif (n <= 3e-74) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (n <= -1.2e-52) tmp = 1.0; elseif (n <= 3e-74) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[n, -1.2e-52], 1.0, If[LessEqual[n, 3e-74], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -1.2 \cdot 10^{-52}:\\
\;\;\;\;1\\
\mathbf{elif}\;n \leq 3 \cdot 10^{-74}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if n < -1.2000000000000001e-52 or 3.00000000000000007e-74 < n Initial program 99.9%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 71.4%
if -1.2000000000000001e-52 < n < 3.00000000000000007e-74Initial program 100.0%
/-rgt-identity100.0%
metadata-eval100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
metadata-eval100.0%
metadata-eval100.0%
associate-/r*100.0%
neg-mul-1100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around inf 82.9%
Final simplification76.0%
(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%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
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%
/-rgt-identity99.9%
metadata-eval99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
metadata-eval99.9%
metadata-eval99.9%
associate-/r*99.9%
neg-mul-199.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around inf 48.7%
Final simplification48.7%
herbie shell --seed 2024018
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))