
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))
double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / x)
end function
public static double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / x);
}
def code(x): return (1.0 / (x + 1.0)) - (1.0 / x)
function code(x) return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / x)) end
function tmp = code(x) tmp = (1.0 / (x + 1.0)) - (1.0 / x); end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + 1} - \frac{1}{x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))
double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / x)
end function
public static double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / x);
}
def code(x): return (1.0 / (x + 1.0)) - (1.0 / x)
function code(x) return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / x)) end
function tmp = code(x) tmp = (1.0 / (x + 1.0)) - (1.0 / x); end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + 1} - \frac{1}{x}
\end{array}
(FPCore (x) :precision binary64 (/ (/ 1.0 x) (- -1.0 x)))
double code(double x) {
return (1.0 / x) / (-1.0 - x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / x) / ((-1.0d0) - x)
end function
public static double code(double x) {
return (1.0 / x) / (-1.0 - x);
}
def code(x): return (1.0 / x) / (-1.0 - x)
function code(x) return Float64(Float64(1.0 / x) / Float64(-1.0 - x)) end
function tmp = code(x) tmp = (1.0 / x) / (-1.0 - x); end
code[x_] := N[(N[(1.0 / x), $MachinePrecision] / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{1}{x}}{-1 - x}
\end{array}
Initial program 75.7%
frac-sub77.3%
div-inv77.3%
*-un-lft-identity77.3%
*-rgt-identity77.3%
+-commutative77.3%
metadata-eval77.3%
frac-times77.3%
clear-num77.3%
associate-*l/77.4%
*-un-lft-identity77.4%
div-inv77.4%
metadata-eval77.4%
*-rgt-identity77.4%
+-commutative77.4%
Applied egg-rr77.4%
Taylor expanded in x around 0 99.9%
Final simplification99.9%
(FPCore (x) :precision binary64 (/ -1.0 (* x (+ 1.0 x))))
double code(double x) {
return -1.0 / (x * (1.0 + x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-1.0d0) / (x * (1.0d0 + x))
end function
public static double code(double x) {
return -1.0 / (x * (1.0 + x));
}
def code(x): return -1.0 / (x * (1.0 + x))
function code(x) return Float64(-1.0 / Float64(x * Float64(1.0 + x))) end
function tmp = code(x) tmp = -1.0 / (x * (1.0 + x)); end
code[x_] := N[(-1.0 / N[(x * N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{x \cdot \left(1 + x\right)}
\end{array}
Initial program 75.7%
sub-neg75.7%
+-commutative75.7%
distribute-neg-frac75.7%
metadata-eval75.7%
Applied egg-rr75.7%
*-rgt-identity75.7%
fma-undefine75.7%
*-inverses75.7%
metadata-eval75.7%
distribute-neg-frac75.7%
fma-neg75.7%
*-inverses75.7%
*-rgt-identity75.7%
*-inverses75.7%
associate-/r*49.1%
*-commutative49.1%
associate-/r*75.7%
div-sub75.8%
*-inverses75.8%
div-sub77.4%
associate-/l/77.3%
+-commutative77.3%
associate--r+99.3%
div-sub99.3%
+-inverses99.3%
div099.3%
associate-/r*99.9%
Simplified99.3%
Final simplification99.3%
(FPCore (x) :precision binary64 (/ (/ -1.0 (+ 1.0 x)) x))
double code(double x) {
return (-1.0 / (1.0 + x)) / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-1.0d0) / (1.0d0 + x)) / x
end function
public static double code(double x) {
return (-1.0 / (1.0 + x)) / x;
}
def code(x): return (-1.0 / (1.0 + x)) / x
function code(x) return Float64(Float64(-1.0 / Float64(1.0 + x)) / x) end
function tmp = code(x) tmp = (-1.0 / (1.0 + x)) / x; end
code[x_] := N[(N[(-1.0 / N[(1.0 + x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-1}{1 + x}}{x}
\end{array}
Initial program 75.7%
frac-sub77.3%
*-rgt-identity77.3%
metadata-eval77.3%
div-inv77.3%
associate-/r*77.4%
*-un-lft-identity77.4%
*-rgt-identity77.4%
+-commutative77.4%
div-inv77.4%
metadata-eval77.4%
*-rgt-identity77.4%
+-commutative77.4%
Applied egg-rr77.4%
frac-2neg77.4%
div-inv77.4%
+-commutative77.4%
+-commutative77.4%
distribute-neg-in77.4%
neg-mul-177.4%
metadata-eval77.4%
fma-define77.4%
Applied egg-rr77.4%
associate-*r/77.4%
*-rgt-identity77.4%
sub-neg77.4%
distribute-neg-in77.4%
neg-mul-177.4%
distribute-neg-in77.4%
neg-mul-177.4%
metadata-eval77.4%
fma-undefine77.4%
neg-mul-177.4%
distribute-lft-in77.4%
fma-undefine77.4%
neg-mul-177.4%
associate-+r+99.9%
sub-neg99.9%
+-inverses99.9%
metadata-eval99.9%
metadata-eval99.9%
fma-undefine99.9%
neg-mul-199.9%
+-commutative99.9%
unsub-neg99.9%
Simplified99.9%
Final simplification99.9%
(FPCore (x) :precision binary64 (/ -1.0 x))
double code(double x) {
return -1.0 / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-1.0d0) / x
end function
public static double code(double x) {
return -1.0 / x;
}
def code(x): return -1.0 / x
function code(x) return Float64(-1.0 / x) end
function tmp = code(x) tmp = -1.0 / x; end
code[x_] := N[(-1.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{x}
\end{array}
Initial program 75.7%
Taylor expanded in x around 0 47.1%
Final simplification47.1%
(FPCore (x) :precision binary64 1.0)
double code(double x) {
return 1.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0
end function
public static double code(double x) {
return 1.0;
}
def code(x): return 1.0
function code(x) return 1.0 end
function tmp = code(x) tmp = 1.0; end
code[x_] := 1.0
\begin{array}{l}
\\
1
\end{array}
Initial program 75.7%
frac-sub77.3%
*-rgt-identity77.3%
metadata-eval77.3%
div-inv77.3%
associate-/r*77.4%
*-un-lft-identity77.4%
*-rgt-identity77.4%
+-commutative77.4%
div-inv77.4%
metadata-eval77.4%
*-rgt-identity77.4%
+-commutative77.4%
Applied egg-rr77.4%
Taylor expanded in x around 0 45.4%
Taylor expanded in x around inf 2.8%
Final simplification2.8%
herbie shell --seed 2024048
(FPCore (x)
:name "2frac (problem 3.3.1)"
:precision binary64
(- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))