
(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 (pow (/ (- n f) (+ n f)) -1.0))
double code(double f, double n) {
return pow(((n - f) / (n + f)), -1.0);
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = ((n - f) / (n + f)) ** (-1.0d0)
end function
public static double code(double f, double n) {
return Math.pow(((n - f) / (n + f)), -1.0);
}
def code(f, n): return math.pow(((n - f) / (n + f)), -1.0)
function code(f, n) return Float64(Float64(n - f) / Float64(n + f)) ^ -1.0 end
function tmp = code(f, n) tmp = ((n - f) / (n + f)) ^ -1.0; end
code[f_, n_] := N[Power[N[(N[(n - f), $MachinePrecision] / N[(n + f), $MachinePrecision]), $MachinePrecision], -1.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{n - f}{n + f}\right)}^{-1}
\end{array}
Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (or (<= n -1.95e-22) (not (<= n 1.55e-59))) (+ 1.0 (* 2.0 (/ f n))) -1.0))
double code(double f, double n) {
double tmp;
if ((n <= -1.95e-22) || !(n <= 1.55e-59)) {
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 <= (-1.95d-22)) .or. (.not. (n <= 1.55d-59))) 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 <= -1.95e-22) || !(n <= 1.55e-59)) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -1.95e-22) or not (n <= 1.55e-59): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if ((n <= -1.95e-22) || !(n <= 1.55e-59)) 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 <= -1.95e-22) || ~((n <= 1.55e-59))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -1.95e-22], N[Not[LessEqual[n, 1.55e-59]], $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 -1.95 \cdot 10^{-22} \lor \neg \left(n \leq 1.55 \cdot 10^{-59}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if n < -1.94999999999999999e-22 or 1.55e-59 < n Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around 0 77.5%
if -1.94999999999999999e-22 < n < 1.55e-59Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around inf 82.8%
Final simplification80.0%
(FPCore (f n) :precision binary64 (if (or (<= n -4.75e+24) (not (<= n 1.1e-56))) (+ 1.0 (* 2.0 (/ f n))) (+ -1.0 (* -2.0 (/ n f)))))
double code(double f, double n) {
double tmp;
if ((n <= -4.75e+24) || !(n <= 1.1e-56)) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0 + (-2.0 * (n / f));
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((n <= (-4.75d+24)) .or. (.not. (n <= 1.1d-56))) then
tmp = 1.0d0 + (2.0d0 * (f / n))
else
tmp = (-1.0d0) + ((-2.0d0) * (n / f))
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((n <= -4.75e+24) || !(n <= 1.1e-56)) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0 + (-2.0 * (n / f));
}
return tmp;
}
def code(f, n): tmp = 0 if (n <= -4.75e+24) or not (n <= 1.1e-56): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 + (-2.0 * (n / f)) return tmp
function code(f, n) tmp = 0.0 if ((n <= -4.75e+24) || !(n <= 1.1e-56)) tmp = Float64(1.0 + Float64(2.0 * Float64(f / n))); else tmp = Float64(-1.0 + Float64(-2.0 * Float64(n / f))); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((n <= -4.75e+24) || ~((n <= 1.1e-56))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0 + (-2.0 * (n / f)); end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[n, -4.75e+24], N[Not[LessEqual[n, 1.1e-56]], $MachinePrecision]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(-1.0 + N[(-2.0 * N[(n / f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -4.75 \cdot 10^{+24} \lor \neg \left(n \leq 1.1 \cdot 10^{-56}\right):\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1 + -2 \cdot \frac{n}{f}\\
\end{array}
\end{array}
if n < -4.7500000000000001e24 or 1.10000000000000002e-56 < n Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around 0 78.7%
if -4.7500000000000001e24 < n < 1.10000000000000002e-56Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in n around 0 81.9%
Final simplification80.2%
(FPCore (f n) :precision binary64 (if (<= n -5e-20) 1.0 (if (<= n 1.4e-58) -1.0 1.0)))
double code(double f, double n) {
double tmp;
if (n <= -5e-20) {
tmp = 1.0;
} else if (n <= 1.4e-58) {
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 <= (-5d-20)) then
tmp = 1.0d0
else if (n <= 1.4d-58) 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 <= -5e-20) {
tmp = 1.0;
} else if (n <= 1.4e-58) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if n <= -5e-20: tmp = 1.0 elif n <= 1.4e-58: tmp = -1.0 else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if (n <= -5e-20) tmp = 1.0; elseif (n <= 1.4e-58) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (n <= -5e-20) tmp = 1.0; elseif (n <= 1.4e-58) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[n, -5e-20], 1.0, If[LessEqual[n, 1.4e-58], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;n \leq -5 \cdot 10^{-20}:\\
\;\;\;\;1\\
\mathbf{elif}\;n \leq 1.4 \cdot 10^{-58}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if n < -4.9999999999999999e-20 or 1.4e-58 < n Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around 0 76.6%
if -4.9999999999999999e-20 < n < 1.4e-58Initial program 100.0%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around inf 82.8%
Final simplification79.5%
(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%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Final simplification100.0%
(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%
distribute-frac-neg100.0%
distribute-neg-frac2100.0%
sub-neg100.0%
+-commutative100.0%
distribute-neg-in100.0%
remove-double-neg100.0%
sub-neg100.0%
Simplified100.0%
Taylor expanded in f around inf 51.6%
Final simplification51.6%
herbie shell --seed 2024085
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))