
(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 5 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 (or (<= f -2.2e-41) (not (<= f 5.2e-25))) (/ f (- n f)) (/ n (- n f))))
double code(double f, double n) {
double tmp;
if ((f <= -2.2e-41) || !(f <= 5.2e-25)) {
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 <= (-2.2d-41)) .or. (.not. (f <= 5.2d-25))) 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 <= -2.2e-41) || !(f <= 5.2e-25)) {
tmp = f / (n - f);
} else {
tmp = n / (n - f);
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -2.2e-41) or not (f <= 5.2e-25): tmp = f / (n - f) else: tmp = n / (n - f) return tmp
function code(f, n) tmp = 0.0 if ((f <= -2.2e-41) || !(f <= 5.2e-25)) 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 <= -2.2e-41) || ~((f <= 5.2e-25))) tmp = f / (n - f); else tmp = n / (n - f); end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -2.2e-41], N[Not[LessEqual[f, 5.2e-25]], $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 -2.2 \cdot 10^{-41} \lor \neg \left(f \leq 5.2 \cdot 10^{-25}\right):\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{else}:\\
\;\;\;\;\frac{n}{n - f}\\
\end{array}
\end{array}
if f < -2.2e-41 or 5.2e-25 < 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 76.7%
if -2.2e-41 < f < 5.2e-25Initial 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 75.2%
Final simplification76.0%
(FPCore (f n) :precision binary64 (if (or (<= f -1.9e-94) (not (<= f 3e-84))) (/ f (- n f)) 1.0))
double code(double f, double n) {
double tmp;
if ((f <= -1.9e-94) || !(f <= 3e-84)) {
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 <= (-1.9d-94)) .or. (.not. (f <= 3d-84))) 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 <= -1.9e-94) || !(f <= 3e-84)) {
tmp = f / (n - f);
} else {
tmp = 1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if (f <= -1.9e-94) or not (f <= 3e-84): tmp = f / (n - f) else: tmp = 1.0 return tmp
function code(f, n) tmp = 0.0 if ((f <= -1.9e-94) || !(f <= 3e-84)) 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 <= -1.9e-94) || ~((f <= 3e-84))) tmp = f / (n - f); else tmp = 1.0; end tmp_2 = tmp; end
code[f_, n_] := If[Or[LessEqual[f, -1.9e-94], N[Not[LessEqual[f, 3e-84]], $MachinePrecision]], N[(f / N[(n - f), $MachinePrecision]), $MachinePrecision], 1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -1.9 \cdot 10^{-94} \lor \neg \left(f \leq 3 \cdot 10^{-84}\right):\\
\;\;\;\;\frac{f}{n - f}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if f < -1.9e-94 or 3.0000000000000001e-84 < 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 73.3%
if -1.9e-94 < f < 3.0000000000000001e-84Initial 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 80.0%
Final simplification75.7%
(FPCore (f n) :precision binary64 (if (<= f -2.2e-41) -1.0 (if (<= f 3.8e-84) 1.0 -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -2.2e-41) {
tmp = -1.0;
} else if (f <= 3.8e-84) {
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 <= (-2.2d-41)) then
tmp = -1.0d0
else if (f <= 3.8d-84) 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 <= -2.2e-41) {
tmp = -1.0;
} else if (f <= 3.8e-84) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -2.2e-41: tmp = -1.0 elif f <= 3.8e-84: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -2.2e-41) tmp = -1.0; elseif (f <= 3.8e-84) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -2.2e-41) tmp = -1.0; elseif (f <= 3.8e-84) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -2.2e-41], -1.0, If[LessEqual[f, 3.8e-84], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2.2 \cdot 10^{-41}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 3.8 \cdot 10^{-84}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -2.2e-41 or 3.79999999999999986e-84 < 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 74.5%
if -2.2e-41 < f < 3.79999999999999986e-84Initial 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 76.0%
(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 53.8%
herbie shell --seed 2024128
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))