
(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 (/ 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 100.0%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
clear-num100.0%
associate-/r/99.7%
Applied egg-rr99.7%
associate-/r/100.0%
+-commutative100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (or (<= f -5.2e+22) (not (<= f 6500000000.0))) (+ (* -2.0 (/ n f)) -1.0) (+ 1.0 (* 2.0 (/ f n)))))
double code(double f, double n) {
double tmp;
if ((f <= -5.2e+22) || !(f <= 6500000000.0)) {
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 <= (-5.2d+22)) .or. (.not. (f <= 6500000000.0d0))) 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 <= -5.2e+22) || !(f <= 6500000000.0)) {
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 <= -5.2e+22) or not (f <= 6500000000.0): 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 <= -5.2e+22) || !(f <= 6500000000.0)) 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 <= -5.2e+22) || ~((f <= 6500000000.0))) 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, -5.2e+22], N[Not[LessEqual[f, 6500000000.0]], $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 -5.2 \cdot 10^{+22} \lor \neg \left(f \leq 6500000000\right):\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\end{array}
\end{array}
if f < -5.2e22 or 6.5e9 < f Initial program 100.0%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
Taylor expanded in n around 0 78.1%
if -5.2e22 < f < 6.5e9Initial program 99.9%
neg-mul-199.9%
remove-double-neg99.9%
unsub-neg99.9%
distribute-neg-in99.9%
neg-mul-199.9%
times-frac99.9%
metadata-eval99.9%
+-commutative99.9%
+-commutative99.9%
sub-neg99.9%
*-lft-identity99.9%
+-commutative99.9%
Simplified99.9%
Taylor expanded in f around 0 76.6%
Final simplification77.3%
(FPCore (f n) :precision binary64 (if (<= f -4.2e+15) -1.0 (if (<= f 43000000000.0) (+ 1.0 (* 2.0 (/ f n))) -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -4.2e+15) {
tmp = -1.0;
} else if (f <= 43000000000.0) {
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+15)) then
tmp = -1.0d0
else if (f <= 43000000000.0d0) 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+15) {
tmp = -1.0;
} else if (f <= 43000000000.0) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -4.2e+15: tmp = -1.0 elif f <= 43000000000.0: tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -4.2e+15) tmp = -1.0; elseif (f <= 43000000000.0) 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+15) tmp = -1.0; elseif (f <= 43000000000.0) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -4.2e+15], -1.0, If[LessEqual[f, 43000000000.0], 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^{+15}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 43000000000:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -4.2e15 or 4.3e10 < f Initial program 100.0%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
Taylor expanded in f around inf 77.7%
if -4.2e15 < f < 4.3e10Initial program 99.9%
neg-mul-199.9%
remove-double-neg99.9%
unsub-neg99.9%
distribute-neg-in99.9%
neg-mul-199.9%
times-frac99.9%
metadata-eval99.9%
+-commutative99.9%
+-commutative99.9%
sub-neg99.9%
*-lft-identity99.9%
+-commutative99.9%
Simplified99.9%
Taylor expanded in f around 0 76.6%
Final simplification77.1%
(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%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (f n) :precision binary64 (if (<= f -5e+23) -1.0 (if (<= f 9e-34) 1.0 -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -5e+23) {
tmp = -1.0;
} else if (f <= 9e-34) {
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 <= (-5d+23)) then
tmp = -1.0d0
else if (f <= 9d-34) 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 <= -5e+23) {
tmp = -1.0;
} else if (f <= 9e-34) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -5e+23: tmp = -1.0 elif f <= 9e-34: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -5e+23) tmp = -1.0; elseif (f <= 9e-34) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -5e+23) tmp = -1.0; elseif (f <= 9e-34) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -5e+23], -1.0, If[LessEqual[f, 9e-34], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -5 \cdot 10^{+23}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 9 \cdot 10^{-34}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -4.9999999999999999e23 or 9.00000000000000085e-34 < f Initial program 100.0%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
Taylor expanded in f around inf 76.8%
if -4.9999999999999999e23 < f < 9.00000000000000085e-34Initial program 99.9%
neg-mul-199.9%
remove-double-neg99.9%
unsub-neg99.9%
distribute-neg-in99.9%
neg-mul-199.9%
times-frac99.9%
metadata-eval99.9%
+-commutative99.9%
+-commutative99.9%
sub-neg99.9%
*-lft-identity99.9%
+-commutative99.9%
Simplified99.9%
Taylor expanded in f around 0 76.0%
Final simplification76.4%
(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%
neg-mul-1100.0%
remove-double-neg100.0%
unsub-neg100.0%
distribute-neg-in100.0%
neg-mul-1100.0%
times-frac100.0%
metadata-eval100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
*-lft-identity100.0%
+-commutative100.0%
Simplified100.0%
Taylor expanded in f around inf 48.9%
Final simplification48.9%
herbie shell --seed 2023333
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))