
(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 (+ (+ 1.0 (/ (+ n f) (- n f))) -1.0))
double code(double f, double n) {
return (1.0 + ((n + f) / (n - f))) + -1.0;
}
real(8) function code(f, n)
real(8), intent (in) :: f
real(8), intent (in) :: n
code = (1.0d0 + ((n + f) / (n - f))) + (-1.0d0)
end function
public static double code(double f, double n) {
return (1.0 + ((n + f) / (n - f))) + -1.0;
}
def code(f, n): return (1.0 + ((n + f) / (n - f))) + -1.0
function code(f, n) return Float64(Float64(1.0 + Float64(Float64(n + f) / Float64(n - f))) + -1.0) end
function tmp = code(f, n) tmp = (1.0 + ((n + f) / (n - f))) + -1.0; end
code[f_, n_] := N[(N[(1.0 + N[(N[(n + f), $MachinePrecision] / N[(n - f), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]
\begin{array}{l}
\\
\left(1 + \frac{n + f}{n - f}\right) + -1
\end{array}
Initial 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%
clear-num99.9%
associate-/r/99.7%
Applied egg-rr99.7%
associate-*l/99.9%
*-un-lft-identity99.9%
expm1-log1p-u99.2%
expm1-undefine99.2%
log1p-undefine99.2%
rem-exp-log99.9%
+-commutative99.9%
Applied egg-rr99.9%
Final simplification99.9%
(FPCore (f n) :precision binary64 (if (<= f -5.9e-9) -1.0 (if (<= f 1.85e+133) (+ 1.0 (* 2.0 (/ f n))) -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -5.9e-9) {
tmp = -1.0;
} else if (f <= 1.85e+133) {
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 <= (-5.9d-9)) then
tmp = -1.0d0
else if (f <= 1.85d+133) 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 <= -5.9e-9) {
tmp = -1.0;
} else if (f <= 1.85e+133) {
tmp = 1.0 + (2.0 * (f / n));
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -5.9e-9: tmp = -1.0 elif f <= 1.85e+133: tmp = 1.0 + (2.0 * (f / n)) else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -5.9e-9) tmp = -1.0; elseif (f <= 1.85e+133) 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 <= -5.9e-9) tmp = -1.0; elseif (f <= 1.85e+133) tmp = 1.0 + (2.0 * (f / n)); else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -5.9e-9], -1.0, If[LessEqual[f, 1.85e+133], N[(1.0 + N[(2.0 * N[(f / n), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -5.9 \cdot 10^{-9}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 1.85 \cdot 10^{+133}:\\
\;\;\;\;1 + 2 \cdot \frac{f}{n}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -5.8999999999999999e-9 or 1.85000000000000012e133 < f Initial 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 inf 77.0%
if -5.8999999999999999e-9 < f < 1.85000000000000012e133Initial 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 75.5%
Final simplification76.1%
(FPCore (f n) :precision binary64 (if (<= f -1.45e-9) -1.0 (if (<= f 1.8e+133) 1.0 -1.0)))
double code(double f, double n) {
double tmp;
if (f <= -1.45e-9) {
tmp = -1.0;
} else if (f <= 1.8e+133) {
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 <= (-1.45d-9)) then
tmp = -1.0d0
else if (f <= 1.8d+133) 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 <= -1.45e-9) {
tmp = -1.0;
} else if (f <= 1.8e+133) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(f, n): tmp = 0 if f <= -1.45e-9: tmp = -1.0 elif f <= 1.8e+133: tmp = 1.0 else: tmp = -1.0 return tmp
function code(f, n) tmp = 0.0 if (f <= -1.45e-9) tmp = -1.0; elseif (f <= 1.8e+133) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(f, n) tmp = 0.0; if (f <= -1.45e-9) tmp = -1.0; elseif (f <= 1.8e+133) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[f_, n_] := If[LessEqual[f, -1.45e-9], -1.0, If[LessEqual[f, 1.8e+133], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;f \leq -1.45 \cdot 10^{-9}:\\
\;\;\;\;-1\\
\mathbf{elif}\;f \leq 1.8 \cdot 10^{+133}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if f < -1.44999999999999996e-9 or 1.79999999999999989e133 < f Initial 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 inf 77.0%
if -1.44999999999999996e-9 < f < 1.79999999999999989e133Initial 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 73.9%
Final simplification75.2%
(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%
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%
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%
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 inf 46.2%
Final simplification46.2%
herbie shell --seed 2024067
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))