
(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 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%
log1p-expm1-u99.9%
Applied egg-rr99.9%
log1p-expm1-u100.0%
div-inv99.8%
*-commutative99.8%
+-commutative99.8%
distribute-rgt-in99.8%
un-div-inv99.9%
un-div-inv100.0%
Applied egg-rr100.0%
(FPCore (f n)
:precision binary64
(if (or (<= f -2.85e+171)
(and (not (<= f -8.6e+122))
(or (<= f -7.6e-28) (not (<= f 8.5e+64)))))
(+ (* -2.0 (/ n f)) -1.0)
(+ 1.0 (* 2.0 (/ f n)))))
double code(double f, double n) {
double tmp;
if ((f <= -2.85e+171) || (!(f <= -8.6e+122) && ((f <= -7.6e-28) || !(f <= 8.5e+64)))) {
tmp = (-2.0 * (n / f)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (f / n));
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((f <= (-2.85d+171)) .or. (.not. (f <= (-8.6d+122))) .and. (f <= (-7.6d-28)) .or. (.not. (f <= 8.5d+64))) then
tmp = ((-2.0d0) * (n / f)) + (-1.0d0)
else
tmp = 1.0d0 + (2.0d0 * (f / n))
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((f <= -2.85e+171) || (!(f <= -8.6e+122) && ((f <= -7.6e-28) || !(f <= 8.5e+64)))) {
tmp = (-2.0 * (n / f)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (f / n));
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -2.85e+171) or (not (f <= -8.6e+122) and ((f <= -7.6e-28) or not (f <= 8.5e+64))): tmp = (-2.0 * (n / f)) + -1.0 else: tmp = 1.0 + (2.0 * (f / n)) return tmp
function code(f, n) tmp = 0.0 if ((f <= -2.85e+171) || (!(f <= -8.6e+122) && ((f <= -7.6e-28) || !(f <= 8.5e+64)))) tmp = Float64(Float64(-2.0 * Float64(n / f)) + -1.0); else tmp = Float64(1.0 + Float64(2.0 * Float64(f / n))); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((f <= -2.85e+171) || (~((f <= -8.6e+122)) && ((f <= -7.6e-28) || ~((f <= 8.5e+64))))) tmp = (-2.0 * (n / f)) + -1.0; else tmp = 1.0 + (2.0 * (f / n)); end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -2.85e+171], And[N[Not[LessEqual[f, -8.6e+122]], $MachinePrecision], Or[LessEqual[f, -7.6e-28], N[Not[LessEqual[f, 8.5e+64]], $MachinePrecision]]]], N[(N[(-2.0 * N[(n / f), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2.85 \cdot 10^{+171} \lor \neg \left(f \leq -8.6 \cdot 10^{+122}\right) \land \left(f \leq -7.6 \cdot 10^{-28} \lor \neg \left(f \leq 8.5 \cdot 10^{+64}\right)\right):\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\end{array}
\end{array}
if f < -2.85e171 or -8.59999999999999943e122 < f < -7.60000000000000018e-28 or 8.4999999999999998e64 < f 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 n around 0 85.9%
if -2.85e171 < f < -8.59999999999999943e122 or -7.60000000000000018e-28 < f < 8.4999999999999998e64Initial program 99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 74.8%
Final simplification79.4%
(FPCore (f n)
:precision binary64
(if (<= f -3.1e+171)
-1.0
(if (or (<= f -8.6e+122) (and (not (<= f -3e-28)) (<= f 2.3e+64)))
(+ 1.0 (* 2.0 (/ f n)))
-1.0)))
double code(double f, double n) {
double tmp;
if (f <= -3.1e+171) {
tmp = -1.0;
} else if ((f <= -8.6e+122) || (!(f <= -3e-28) && (f <= 2.3e+64))) {
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 (f <= (-3.1d+171)) then
tmp = -1.0d0
else if ((f <= (-8.6d+122)) .or. (.not. (f <= (-3d-28))) .and. (f <= 2.3d+64)) 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 (f <= -3.1e+171) {
tmp = -1.0;
} else if ((f <= -8.6e+122) || (!(f <= -3e-28) && (f <= 2.3e+64))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -3.1e+171: tmp = -1.0 elif (f <= -8.6e+122) or (not (f <= -3e-28) and (f <= 2.3e+64)): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -3.1e+171) tmp = -1.0; elseif ((f <= -8.6e+122) || (!(f <= -3e-28) && (f <= 2.3e+64))) 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 (f <= -3.1e+171) tmp = -1.0; elseif ((f <= -8.6e+122) || (~((f <= -3e-28)) && (f <= 2.3e+64))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -3.1e+171], -1.0, If[Or[LessEqual[f, -8.6e+122], And[N[Not[LessEqual[f, -3e-28]], $MachinePrecision], LessEqual[f, 2.3e+64]]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -3.1 \cdot 10^{+171}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq -8.6 \cdot 10^{+122} \lor \neg \left(f \leq -3 \cdot 10^{-28}\right) \land f \leq 2.3 \cdot 10^{+64}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -3.0999999999999999e171 or -8.59999999999999943e122 < f < -3.00000000000000003e-28 or 2.3e64 < f 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 84.9%
if -3.0999999999999999e171 < f < -8.59999999999999943e122 or -3.00000000000000003e-28 < f < 2.3e64Initial program 99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 74.8%
Final simplification79.0%
(FPCore (f n)
:precision binary64
(if (<= f -2.85e+171)
-1.0
(if (<= f -8.6e+122)
1.0
(if (<= f -7e-28) -1.0 (if (<= f 2.4e+64) 1.0 -1.0)))))
double code(double f, double n) {
double tmp;
if (f <= -2.85e+171) {
tmp = -1.0;
} else if (f <= -8.6e+122) {
tmp = 1.0;
} else if (f <= -7e-28) {
tmp = -1.0;
} else if (f <= 2.4e+64) {
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 (f <= (-2.85d+171)) then
tmp = -1.0d0
else if (f <= (-8.6d+122)) then
tmp = 1.0d0
else if (f <= (-7d-28)) then
tmp = -1.0d0
else if (f <= 2.4d+64) 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 (f <= -2.85e+171) {
tmp = -1.0;
} else if (f <= -8.6e+122) {
tmp = 1.0;
} else if (f <= -7e-28) {
tmp = -1.0;
} else if (f <= 2.4e+64) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -2.85e+171: tmp = -1.0 elif f <= -8.6e+122: tmp = 1.0 elif f <= -7e-28: tmp = -1.0 elif f <= 2.4e+64: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -2.85e+171) tmp = -1.0; elseif (f <= -8.6e+122) tmp = 1.0; elseif (f <= -7e-28) tmp = -1.0; elseif (f <= 2.4e+64) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -2.85e+171) tmp = -1.0; elseif (f <= -8.6e+122) tmp = 1.0; elseif (f <= -7e-28) tmp = -1.0; elseif (f <= 2.4e+64) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -2.85e+171], -1.0, If[LessEqual[f, -8.6e+122], 1.0, If[LessEqual[f, -7e-28], -1.0, If[LessEqual[f, 2.4e+64], 1.0, -1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2.85 \cdot 10^{+171}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq -8.6 \cdot 10^{+122}:\\
\;\;\;\;1\\
\mathbf{elif}\;f \leq -7 \cdot 10^{-28}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 2.4 \cdot 10^{+64}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -2.85e171 or -8.59999999999999943e122 < f < -6.9999999999999999e-28 or 2.39999999999999999e64 < f 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 84.9%
if -2.85e171 < f < -8.59999999999999943e122 or -6.9999999999999999e-28 < f < 2.39999999999999999e64Initial program 99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 73.1%
(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%
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 50.1%
herbie shell --seed 2024103
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))