
(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 7 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 (/ (+ f n) (- n f)))
double code(double f, double n) {
return (f + n) / (n - f);
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = (f + n) / (n - f)
end function
public static double code(double f, double n) {
return (f + n) / (n - f);
}
def code(f, n): return (f + n) / (n - f)
function code(f, n) return Float64(Float64(f + n) / Float64(n - f)) end
function tmp = code(f, n) tmp = (f + n) / (n - f); end
code[f_, n_] := N[(N[(f + n), $MachinePrecision] / N[(n - f), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{f + n}{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%
(FPCore (f n) :precision binary64 (if (<= f -9.5e+17) (/ f (- n f)) (if (<= f 1.06e-72) (/ (+ f n) n) (/ (+ f n) (- f)))))
double code(double f, double n) {
double tmp;
if (f <= -9.5e+17) {
tmp = f / (n - f);
} else if (f <= 1.06e-72) {
tmp = (f + n) / n;
} else {
tmp = (f + n) / -f;
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if (f <= (-9.5d+17)) then
tmp = f / (n - f)
else if (f <= 1.06d-72) then
tmp = (f + n) / n
else
tmp = (f + n) / -f
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if (f <= -9.5e+17) {
tmp = f / (n - f);
} else if (f <= 1.06e-72) {
tmp = (f + n) / n;
} else {
tmp = (f + n) / -f;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -9.5e+17: tmp = f / (n - f) elif f <= 1.06e-72: tmp = (f + n) / n else: tmp = (f + n) / -f return tmp
function code(f, n) tmp = 0.0 if (f <= -9.5e+17) tmp = Float64(f / Float64(n - f)); elseif (f <= 1.06e-72) tmp = Float64(Float64(f + n) / n); else tmp = Float64(Float64(f + n) / Float64(-f)); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -9.5e+17) tmp = f / (n - f); elseif (f <= 1.06e-72) tmp = (f + n) / n; else tmp = (f + n) / -f; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -9.5e+17], N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision], If[LessEqual[f, 1.06e-72], N[(N[(f + n), $MachinePrecision] / n), $MachinePrecision], N[(N[(f + n), $MachinePrecision] / (-f)), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -9.5 \cdot 10^{+17}:\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{elif}\;f \leq 1.06 \cdot 10^{-72}:\\
\;\;\;\;\frac{f + n}{n}\\
\mathbf{else}:\\
\;\;\;\;\frac{f + n}{-f}\\
\end{array}
\end{array}
if f < -9.5e17Initial 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 87.4%
if -9.5e17 < f < 1.05999999999999994e-72Initial 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 inf 100.0%
mul-1-neg100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in n around inf 81.1%
if 1.05999999999999994e-72 < 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 74.7%
neg-mul-174.7%
Simplified74.7%
(FPCore (f n) :precision binary64 (if (or (<= f -4.6e+19) (not (<= f 1.06e-72))) (/ f (- n f)) (/ (+ f n) n)))
double code(double f, double n) {
double tmp;
if ((f <= -4.6e+19) || !(f <= 1.06e-72)) {
tmp = f / (n - f);
} else {
tmp = (f + n) / n;
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((f <= (-4.6d+19)) .or. (.not. (f <= 1.06d-72))) then
tmp = f / (n - f)
else
tmp = (f + n) / n
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((f <= -4.6e+19) || !(f <= 1.06e-72)) {
tmp = f / (n - f);
} else {
tmp = (f + n) / n;
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -4.6e+19) or not (f <= 1.06e-72): tmp = f / (n - f) else: tmp = (f + n) / n return tmp
function code(f, n) tmp = 0.0 if ((f <= -4.6e+19) || !(f <= 1.06e-72)) tmp = Float64(f / Float64(n - f)); else tmp = Float64(Float64(f + n) / n); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((f <= -4.6e+19) || ~((f <= 1.06e-72))) tmp = f / (n - f); else tmp = (f + n) / n; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -4.6e+19], N[Not[LessEqual[f, 1.06e-72]], $MachinePrecision]], N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision], N[(N[(f + n), $MachinePrecision] / n), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -4.6 \cdot 10^{+19} \lor \neg \left(f \leq 1.06 \cdot 10^{-72}\right):\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{else}:\\
\;\;\;\;\frac{f + n}{n}\\
\end{array}
\end{array}
if f < -4.6e19 or 1.05999999999999994e-72 < 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 80.2%
if -4.6e19 < f < 1.05999999999999994e-72Initial 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 inf 100.0%
mul-1-neg100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in n around inf 81.1%
Final simplification80.6%
(FPCore (f n) :precision binary64 (if (or (<= f -2.95e+19) (not (<= f 5.7e-70))) (/ f (- n f)) (/ n (- n f))))
double code(double f, double n) {
double tmp;
if ((f <= -2.95e+19) || !(f <= 5.7e-70)) {
tmp = f / (n - f);
} else {
tmp = n / (n - f);
}
return tmp;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
real(8) :: tmp
if ((f <= (-2.95d+19)) .or. (.not. (f <= 5.7d-70))) then
tmp = f / (n - f)
else
tmp = n / (n - f)
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((f <= -2.95e+19) || !(f <= 5.7e-70)) {
tmp = f / (n - f);
} else {
tmp = n / (n - f);
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -2.95e+19) or not (f <= 5.7e-70): tmp = f / (n - f) else: tmp = n / (n - f) return tmp
function code(f, n) tmp = 0.0 if ((f <= -2.95e+19) || !(f <= 5.7e-70)) tmp = Float64(f / Float64(n - f)); else tmp = Float64(n / Float64(n - f)); end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((f <= -2.95e+19) || ~((f <= 5.7e-70))) tmp = f / (n - f); else tmp = n / (n - f); end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -2.95e+19], N[Not[LessEqual[f, 5.7e-70]], $MachinePrecision]], N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision], N[(n / N[(n - f), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2.95 \cdot 10^{+19} \lor \neg \left(f \leq 5.7 \cdot 10^{-70}\right):\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{else}:\\
\;\;\;\;\frac{n}{n - f}\\
\end{array}
\end{array}
if f < -2.95e19 or 5.70000000000000028e-70 < 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 80.6%
if -2.95e19 < f < 5.70000000000000028e-70Initial 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 80.3%
Final simplification80.5%
(FPCore (f n) :precision binary64 (if (or (<= f -3.3e+17) (not (<= f 5.1e-73))) (/ f (- n f)) 1.0))
double code(double f, double n) {
double tmp;
if ((f <= -3.3e+17) || !(f <= 5.1e-73)) {
tmp = f / (n - f);
} 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 <= (-3.3d+17)) .or. (.not. (f <= 5.1d-73))) then
tmp = f / (n - f)
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double f, double n) {
double tmp;
if ((f <= -3.3e+17) || !(f <= 5.1e-73)) {
tmp = f / (n - f);
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -3.3e+17) or not (f <= 5.1e-73): tmp = f / (n - f) else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if ((f <= -3.3e+17) || !(f <= 5.1e-73)) tmp = Float64(f / Float64(n - f)); else tmp = 1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if ((f <= -3.3e+17) || ~((f <= 5.1e-73))) tmp = f / (n - f); else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -3.3e+17], N[Not[LessEqual[f, 5.1e-73]], $MachinePrecision]], N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision], 1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -3.3 \cdot 10^{+17} \lor \neg \left(f \leq 5.1 \cdot 10^{-73}\right):\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if f < -3.3e17 or 5.1e-73 < 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 80.2%
if -3.3e17 < f < 5.1e-73Initial 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 80.3%
Final simplification80.2%
(FPCore (f n) :precision binary64 (if (<= f -1e+28) -1.0 (if (<= f 1.05e-72) 1.0 -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -1e+28) {
tmp = -1.0;
} else if (f <= 1.05e-72) {
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 <= (-1d+28)) then
tmp = -1.0d0
else if (f <= 1.05d-72) 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 <= -1e+28) {
tmp = -1.0;
} else if (f <= 1.05e-72) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -1e+28: tmp = -1.0 elif f <= 1.05e-72: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -1e+28) tmp = -1.0; elseif (f <= 1.05e-72) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -1e+28) tmp = -1.0; elseif (f <= 1.05e-72) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -1e+28], -1.0, If[LessEqual[f, 1.05e-72], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -1 \cdot 10^{+28}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 1.05 \cdot 10^{-72}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -9.99999999999999958e27 or 1.05e-72 < 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 79.7%
if -9.99999999999999958e27 < f < 1.05e-72Initial 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 80.3%
(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 51.2%
herbie shell --seed 2024150
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))