
(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 (+ (/ 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%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
unpow-1100.0%
associate-/r/99.8%
+-commutative99.8%
distribute-rgt-in99.8%
un-div-inv99.9%
un-div-inv100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (or (<= f -2.6e+110) (not (<= f 4.4e+15))) (+ (* -2.0 (/ n f)) -1.0) (+ 1.0 (* 2.0 (/ f n)))))
double code(double f, double n) {
double tmp;
if ((f <= -2.6e+110) || !(f <= 4.4e+15)) {
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 <= (-2.6d+110)) .or. (.not. (f <= 4.4d+15))) 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 <= -2.6e+110) || !(f <= 4.4e+15)) {
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 <= -2.6e+110) or not (f <= 4.4e+15): 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 <= -2.6e+110) || !(f <= 4.4e+15)) 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 <= -2.6e+110) || ~((f <= 4.4e+15))) 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, -2.6e+110], N[Not[LessEqual[f, 4.4e+15]], $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 -2.6 \cdot 10^{+110} \lor \neg \left(f \leq 4.4 \cdot 10^{+15}\right):\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\end{array}
\end{array}
if f < -2.6e110 or 4.4e15 < f Initial 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 82.0%
if -2.6e110 < f < 4.4e15Initial 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 75.6%
Final simplification78.0%
(FPCore (f n) :precision binary64 (if (<= f -4.2e+121) -1.0 (if (<= f 1.9e+16) (+ 1.0 (* 2.0 (/ f n))) -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -4.2e+121) {
tmp = -1.0;
} else if (f <= 1.9e+16) {
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 <= (-4.2d+121)) then
tmp = -1.0d0
else if (f <= 1.9d+16) 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 <= -4.2e+121) {
tmp = -1.0;
} else if (f <= 1.9e+16) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -4.2e+121: tmp = -1.0 elif f <= 1.9e+16: tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -4.2e+121) tmp = -1.0; elseif (f <= 1.9e+16) 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 <= -4.2e+121) tmp = -1.0; elseif (f <= 1.9e+16) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -4.2e+121], -1.0, If[LessEqual[f, 1.9e+16], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -4.2 \cdot 10^{+121}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 1.9 \cdot 10^{+16}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -4.2000000000000003e121 or 1.9e16 < f Initial 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 81.9%
if -4.2000000000000003e121 < f < 1.9e16Initial 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 75.3%
Final simplification77.7%
(FPCore (f n) :precision binary64 (if (<= f -2e+109) -1.0 (if (<= f 11500.0) 1.0 -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -2e+109) {
tmp = -1.0;
} else if (f <= 11500.0) {
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 <= (-2d+109)) then
tmp = -1.0d0
else if (f <= 11500.0d0) 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 <= -2e+109) {
tmp = -1.0;
} else if (f <= 11500.0) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -2e+109: tmp = -1.0 elif f <= 11500.0: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -2e+109) tmp = -1.0; elseif (f <= 11500.0) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -2e+109) tmp = -1.0; elseif (f <= 11500.0) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -2e+109], -1.0, If[LessEqual[f, 11500.0], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2 \cdot 10^{+109}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 11500:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -1.99999999999999996e109 or 11500 < f Initial 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 80.0%
if -1.99999999999999996e109 < f < 11500Initial 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 74.8%
Final simplification76.9%
(FPCore (f n) :precision binary64 (/ 1.0 (/ (- n f) (+ n f))))
double code(double f, double n) {
return 1.0 / ((n - f) / (n + f));
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = 1.0d0 / ((n - f) / (n + f))
end function
public static double code(double f, double n) {
return 1.0 / ((n - f) / (n + f));
}
def code(f, n): return 1.0 / ((n - f) / (n + f))
function code(f, n) return Float64(1.0 / Float64(Float64(n - f) / Float64(n + f))) end
function tmp = code(f, n) tmp = 1.0 / ((n - f) / (n + f)); end
code[f_, n_] := N[(1.0 / N[(N[(n - f), $MachinePrecision] / N[(n + f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\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%
clear-num100.0%
inv-pow100.0%
Applied egg-rr100.0%
unpow-1100.0%
+-commutative100.0%
Applied egg-rr100.0%
Final simplification100.0%
(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 46.4%
Final simplification46.4%
herbie shell --seed 2024014
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))