
(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 4 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%
Final simplification100.0%
(FPCore (f n)
:precision binary64
(if (<= f -1.6e+26)
-1.0
(if (or (<= f 6500.0) (and (not (<= f 6e+51)) (<= f 1.95e+90)))
(+ 1.0 (* 2.0 (/ f n)))
-1.0)))
double code(double f, double n) {
double tmp;
if (f <= -1.6e+26) {
tmp = -1.0;
} else if ((f <= 6500.0) || (!(f <= 6e+51) && (f <= 1.95e+90))) {
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 <= (-1.6d+26)) then
tmp = -1.0d0
else if ((f <= 6500.0d0) .or. (.not. (f <= 6d+51)) .and. (f <= 1.95d+90)) 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 <= -1.6e+26) {
tmp = -1.0;
} else if ((f <= 6500.0) || (!(f <= 6e+51) && (f <= 1.95e+90))) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -1.6e+26: tmp = -1.0 elif (f <= 6500.0) or (not (f <= 6e+51) and (f <= 1.95e+90)): tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -1.6e+26) tmp = -1.0; elseif ((f <= 6500.0) || (!(f <= 6e+51) && (f <= 1.95e+90))) 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 <= -1.6e+26) tmp = -1.0; elseif ((f <= 6500.0) || (~((f <= 6e+51)) && (f <= 1.95e+90))) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -1.6e+26], -1.0, If[Or[LessEqual[f, 6500.0], And[N[Not[LessEqual[f, 6e+51]], $MachinePrecision], LessEqual[f, 1.95e+90]]], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -1.6 \cdot 10^{+26}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 6500 \lor \neg \left(f \leq 6 \cdot 10^{+51}\right) \land f \leq 1.95 \cdot 10^{+90}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -1.60000000000000014e26 or 6500 < f < 6e51 or 1.9500000000000001e90 < 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 82.3%
if -1.60000000000000014e26 < f < 6500 or 6e51 < f < 1.9500000000000001e90Initial program 99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 76.5%
Final simplification79.1%
(FPCore (f n)
:precision binary64
(if (<= f -3.55e+25)
-1.0
(if (<= f 2.7e-22)
1.0
(if (<= f 1.4e+52) -1.0 (if (<= f 5e+92) 1.0 -1.0)))))
double code(double f, double n) {
double tmp;
if (f <= -3.55e+25) {
tmp = -1.0;
} else if (f <= 2.7e-22) {
tmp = 1.0;
} else if (f <= 1.4e+52) {
tmp = -1.0;
} else if (f <= 5e+92) {
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 <= (-3.55d+25)) then
tmp = -1.0d0
else if (f <= 2.7d-22) then
tmp = 1.0d0
else if (f <= 1.4d+52) then
tmp = -1.0d0
else if (f <= 5d+92) 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 <= -3.55e+25) {
tmp = -1.0;
} else if (f <= 2.7e-22) {
tmp = 1.0;
} else if (f <= 1.4e+52) {
tmp = -1.0;
} else if (f <= 5e+92) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -3.55e+25: tmp = -1.0 elif f <= 2.7e-22: tmp = 1.0 elif f <= 1.4e+52: tmp = -1.0 elif f <= 5e+92: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -3.55e+25) tmp = -1.0; elseif (f <= 2.7e-22) tmp = 1.0; elseif (f <= 1.4e+52) tmp = -1.0; elseif (f <= 5e+92) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -3.55e+25) tmp = -1.0; elseif (f <= 2.7e-22) tmp = 1.0; elseif (f <= 1.4e+52) tmp = -1.0; elseif (f <= 5e+92) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -3.55e+25], -1.0, If[LessEqual[f, 2.7e-22], 1.0, If[LessEqual[f, 1.4e+52], -1.0, If[LessEqual[f, 5e+92], 1.0, -1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -3.55 \cdot 10^{+25}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 2.7 \cdot 10^{-22}:\\
\;\;\;\;1\\
\mathbf{elif}\;f \leq 1.4 \cdot 10^{+52}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 5 \cdot 10^{+92}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -3.5500000000000001e25 or 2.7000000000000002e-22 < f < 1.4e52 or 5.00000000000000022e92 < 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 81.7%
if -3.5500000000000001e25 < f < 2.7000000000000002e-22 or 1.4e52 < f < 5.00000000000000022e92Initial program 99.9%
distribute-frac-neg99.9%
distribute-neg-frac299.9%
sub-neg99.9%
+-commutative99.9%
distribute-neg-in99.9%
remove-double-neg99.9%
sub-neg99.9%
Simplified99.9%
Taylor expanded in f around 0 75.1%
Final simplification78.2%
(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 50.0%
Final simplification50.0%
herbie shell --seed 2024080
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))