
(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%
/-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%
Final simplification100.0%
(FPCore (f n)
:precision binary64
(if (or (<= f -5.6e+75)
(not
(or (<= f -4.6e-95) (and (not (<= f -5.4e-111)) (<= f 1.2e-28)))))
(+ (* -2.0 (/ n f)) -1.0)
(+ 1.0 (* 2.0 (/ f n)))))
double code(double f, double n) {
double tmp;
if ((f <= -5.6e+75) || !((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 1.2e-28)))) {
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 <= (-5.6d+75)) .or. (.not. (f <= (-4.6d-95)) .or. (.not. (f <= (-5.4d-111))) .and. (f <= 1.2d-28))) 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 <= -5.6e+75) || !((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 1.2e-28)))) {
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 <= -5.6e+75) or not ((f <= -4.6e-95) or (not (f <= -5.4e-111) and (f <= 1.2e-28))): 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 <= -5.6e+75) || !((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 1.2e-28)))) 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 <= -5.6e+75) || ~(((f <= -4.6e-95) || (~((f <= -5.4e-111)) && (f <= 1.2e-28))))) 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, -5.6e+75], N[Not[Or[LessEqual[f, -4.6e-95], And[N[Not[LessEqual[f, -5.4e-111]], $MachinePrecision], LessEqual[f, 1.2e-28]]]], $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 -5.6 \cdot 10^{+75} \lor \neg \left(f \leq -4.6 \cdot 10^{-95} \lor \neg \left(f \leq -5.4 \cdot 10^{-111}\right) \land f \leq 1.2 \cdot 10^{-28}\right):\\
\;\;\;\;-2 \cdot \frac{n}{f} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\end{array}
\end{array}
if f < -5.60000000000000023e75 or -4.59999999999999998e-95 < f < -5.39999999999999977e-111 or 1.2000000000000001e-28 < 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 79.1%
if -5.60000000000000023e75 < f < -4.59999999999999998e-95 or -5.39999999999999977e-111 < f < 1.2000000000000001e-28Initial 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 0 85.1%
Final simplification82.1%
(FPCore (f n)
:precision binary64
(if (<= f -2.15e+76)
-1.0
(if (or (<= f -4.6e-95) (and (not (<= f -5.4e-111)) (<= f 9.8e-26)))
(+ 1.0 (* 2.0 (/ f n)))
-1.0)))
double code(double f, double n) {
double tmp;
if (f <= -2.15e+76) {
tmp = -1.0;
} else if ((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 9.8e-26))) {
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 <= (-2.15d+76)) then
tmp = -1.0d0
else if ((f <= (-4.6d-95)) .or. (.not. (f <= (-5.4d-111))) .and. (f <= 9.8d-26)) 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 <= -2.15e+76) {
tmp = -1.0;
} else if ((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 9.8e-26))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -2.15e+76: tmp = -1.0 elif (f <= -4.6e-95) or (not (f <= -5.4e-111) and (f <= 9.8e-26)): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -2.15e+76) tmp = -1.0; elseif ((f <= -4.6e-95) || (!(f <= -5.4e-111) && (f <= 9.8e-26))) 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 <= -2.15e+76) tmp = -1.0; elseif ((f <= -4.6e-95) || (~((f <= -5.4e-111)) && (f <= 9.8e-26))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -2.15e+76], -1.0, If[Or[LessEqual[f, -4.6e-95], And[N[Not[LessEqual[f, -5.4e-111]], $MachinePrecision], LessEqual[f, 9.8e-26]]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -2.15 \cdot 10^{+76}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq -4.6 \cdot 10^{-95} \lor \neg \left(f \leq -5.4 \cdot 10^{-111}\right) \land f \leq 9.8 \cdot 10^{-26}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -2.14999999999999989e76 or -4.59999999999999998e-95 < f < -5.39999999999999977e-111 or 9.7999999999999998e-26 < 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 77.4%
if -2.14999999999999989e76 < f < -4.59999999999999998e-95 or -5.39999999999999977e-111 < f < 9.7999999999999998e-26Initial 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 0 85.1%
Final simplification81.3%
(FPCore (f n)
:precision binary64
(if (<= f -1e+92)
-1.0
(if (<= f -1e-31)
1.0
(if (<= f -5.4e-111) -1.0 (if (<= f 8.2e-32) 1.0 -1.0)))))
double code(double f, double n) {
double tmp;
if (f <= -1e+92) {
tmp = -1.0;
} else if (f <= -1e-31) {
tmp = 1.0;
} else if (f <= -5.4e-111) {
tmp = -1.0;
} else if (f <= 8.2e-32) {
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+92)) then
tmp = -1.0d0
else if (f <= (-1d-31)) then
tmp = 1.0d0
else if (f <= (-5.4d-111)) then
tmp = -1.0d0
else if (f <= 8.2d-32) 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+92) {
tmp = -1.0;
} else if (f <= -1e-31) {
tmp = 1.0;
} else if (f <= -5.4e-111) {
tmp = -1.0;
} else if (f <= 8.2e-32) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -1e+92: tmp = -1.0 elif f <= -1e-31: tmp = 1.0 elif f <= -5.4e-111: tmp = -1.0 elif f <= 8.2e-32: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -1e+92) tmp = -1.0; elseif (f <= -1e-31) tmp = 1.0; elseif (f <= -5.4e-111) tmp = -1.0; elseif (f <= 8.2e-32) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -1e+92) tmp = -1.0; elseif (f <= -1e-31) tmp = 1.0; elseif (f <= -5.4e-111) tmp = -1.0; elseif (f <= 8.2e-32) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -1e+92], -1.0, If[LessEqual[f, -1e-31], 1.0, If[LessEqual[f, -5.4e-111], -1.0, If[LessEqual[f, 8.2e-32], 1.0, -1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -1 \cdot 10^{+92}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq -1 \cdot 10^{-31}:\\
\;\;\;\;1\\
\mathbf{elif}\;f \leq -5.4 \cdot 10^{-111}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 8.2 \cdot 10^{-32}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -1e92 or -1e-31 < f < -5.39999999999999977e-111 or 8.1999999999999995e-32 < 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 75.1%
if -1e92 < f < -1e-31 or -5.39999999999999977e-111 < f < 8.1999999999999995e-32Initial 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 0 88.2%
Final simplification81.0%
(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%
/-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 46.5%
Final simplification46.5%
herbie shell --seed 2024020
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))