
(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 7 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 / Float64(x + 1.0)) / x) end
function tmp = code(x) tmp = (-1.0 / (x + 1.0)) / x; end
code[x_] := N[(N[(-1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-1}{x + 1}}{x}
\end{array}
Initial program 81.4%
frac-subN/A
div-subN/A
sub-negN/A
*-lft-identityN/A
div-invN/A
metadata-evalN/A
frac-timesN/A
accelerator-lowering-fma.f64N/A
frac-timesN/A
metadata-evalN/A
/-lowering-/.f64N/A
distribute-lft1-inN/A
accelerator-lowering-fma.f64N/A
neg-lowering-neg.f64N/A
metadata-evalN/A
div-invN/A
/-lowering-/.f64N/A
Applied egg-rr81.4%
Applied egg-rr83.0%
distribute-lft1-inN/A
metadata-evalN/A
sub-negN/A
associate-/r*N/A
/-lowering-/.f64N/A
associate--r+N/A
+-inversesN/A
metadata-evalN/A
metadata-evalN/A
/-lowering-/.f64N/A
sub-negN/A
metadata-evalN/A
+-lowering-+.f6499.9
Applied egg-rr99.9%
(FPCore (x)
:precision binary64
(let* ((t_0 (+ (/ 1.0 (+ x 1.0)) (/ -1.0 x))))
(if (<= t_0 -2000000000.0)
(+ 1.0 (/ -1.0 x))
(if (<= t_0 0.0) (/ -1.0 (* x x)) (+ (- 1.0 x) (/ -1.0 x))))))
double code(double x) {
double t_0 = (1.0 / (x + 1.0)) + (-1.0 / x);
double tmp;
if (t_0 <= -2000000000.0) {
tmp = 1.0 + (-1.0 / x);
} else if (t_0 <= 0.0) {
tmp = -1.0 / (x * x);
} else {
tmp = (1.0 - x) + (-1.0 / x);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
real(8) :: tmp
t_0 = (1.0d0 / (x + 1.0d0)) + ((-1.0d0) / x)
if (t_0 <= (-2000000000.0d0)) then
tmp = 1.0d0 + ((-1.0d0) / x)
else if (t_0 <= 0.0d0) then
tmp = (-1.0d0) / (x * x)
else
tmp = (1.0d0 - x) + ((-1.0d0) / x)
end if
code = tmp
end function
public static double code(double x) {
double t_0 = (1.0 / (x + 1.0)) + (-1.0 / x);
double tmp;
if (t_0 <= -2000000000.0) {
tmp = 1.0 + (-1.0 / x);
} else if (t_0 <= 0.0) {
tmp = -1.0 / (x * x);
} else {
tmp = (1.0 - x) + (-1.0 / x);
}
return tmp;
}
def code(x): t_0 = (1.0 / (x + 1.0)) + (-1.0 / x) tmp = 0 if t_0 <= -2000000000.0: tmp = 1.0 + (-1.0 / x) elif t_0 <= 0.0: tmp = -1.0 / (x * x) else: tmp = (1.0 - x) + (-1.0 / x) return tmp
function code(x) t_0 = Float64(Float64(1.0 / Float64(x + 1.0)) + Float64(-1.0 / x)) tmp = 0.0 if (t_0 <= -2000000000.0) tmp = Float64(1.0 + Float64(-1.0 / x)); elseif (t_0 <= 0.0) tmp = Float64(-1.0 / Float64(x * x)); else tmp = Float64(Float64(1.0 - x) + Float64(-1.0 / x)); end return tmp end
function tmp_2 = code(x) t_0 = (1.0 / (x + 1.0)) + (-1.0 / x); tmp = 0.0; if (t_0 <= -2000000000.0) tmp = 1.0 + (-1.0 / x); elseif (t_0 <= 0.0) tmp = -1.0 / (x * x); else tmp = (1.0 - x) + (-1.0 / x); end tmp_2 = tmp; end
code[x_] := Block[{t$95$0 = N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -2000000000.0], N[(1.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.0], N[(-1.0 / N[(x * x), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - x), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{x + 1} + \frac{-1}{x}\\
\mathbf{if}\;t\_0 \leq -2000000000:\\
\;\;\;\;1 + \frac{-1}{x}\\
\mathbf{elif}\;t\_0 \leq 0:\\
\;\;\;\;\frac{-1}{x \cdot x}\\
\mathbf{else}:\\
\;\;\;\;\left(1 - x\right) + \frac{-1}{x}\\
\end{array}
\end{array}
if (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) < -2e9Initial program 100.0%
Taylor expanded in x around 0
Simplified100.0%
if -2e9 < (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) < 0.0Initial program 60.4%
Taylor expanded in x around inf
/-lowering-/.f64N/A
+-rgt-identityN/A
unpow2N/A
accelerator-lowering-fma.f6495.9
Simplified95.9%
+-rgt-identityN/A
*-lowering-*.f6495.9
Applied egg-rr95.9%
if 0.0 < (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) Initial program 100.0%
Taylor expanded in x around 0
mul-1-negN/A
unsub-negN/A
--lowering--.f6499.5
Simplified99.5%
Final simplification97.9%
(FPCore (x)
:precision binary64
(let* ((t_0 (+ (/ 1.0 (+ x 1.0)) (/ -1.0 x))))
(if (<= t_0 -2000000000.0)
(+ 1.0 (/ -1.0 x))
(if (<= t_0 0.0) (/ -1.0 (* x x)) (/ (+ -1.0 x) x)))))
double code(double x) {
double t_0 = (1.0 / (x + 1.0)) + (-1.0 / x);
double tmp;
if (t_0 <= -2000000000.0) {
tmp = 1.0 + (-1.0 / x);
} else if (t_0 <= 0.0) {
tmp = -1.0 / (x * x);
} else {
tmp = (-1.0 + x) / x;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
real(8) :: tmp
t_0 = (1.0d0 / (x + 1.0d0)) + ((-1.0d0) / x)
if (t_0 <= (-2000000000.0d0)) then
tmp = 1.0d0 + ((-1.0d0) / x)
else if (t_0 <= 0.0d0) then
tmp = (-1.0d0) / (x * x)
else
tmp = ((-1.0d0) + x) / x
end if
code = tmp
end function
public static double code(double x) {
double t_0 = (1.0 / (x + 1.0)) + (-1.0 / x);
double tmp;
if (t_0 <= -2000000000.0) {
tmp = 1.0 + (-1.0 / x);
} else if (t_0 <= 0.0) {
tmp = -1.0 / (x * x);
} else {
tmp = (-1.0 + x) / x;
}
return tmp;
}
def code(x): t_0 = (1.0 / (x + 1.0)) + (-1.0 / x) tmp = 0 if t_0 <= -2000000000.0: tmp = 1.0 + (-1.0 / x) elif t_0 <= 0.0: tmp = -1.0 / (x * x) else: tmp = (-1.0 + x) / x return tmp
function code(x) t_0 = Float64(Float64(1.0 / Float64(x + 1.0)) + Float64(-1.0 / x)) tmp = 0.0 if (t_0 <= -2000000000.0) tmp = Float64(1.0 + Float64(-1.0 / x)); elseif (t_0 <= 0.0) tmp = Float64(-1.0 / Float64(x * x)); else tmp = Float64(Float64(-1.0 + x) / x); end return tmp end
function tmp_2 = code(x) t_0 = (1.0 / (x + 1.0)) + (-1.0 / x); tmp = 0.0; if (t_0 <= -2000000000.0) tmp = 1.0 + (-1.0 / x); elseif (t_0 <= 0.0) tmp = -1.0 / (x * x); else tmp = (-1.0 + x) / x; end tmp_2 = tmp; end
code[x_] := Block[{t$95$0 = N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -2000000000.0], N[(1.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.0], N[(-1.0 / N[(x * x), $MachinePrecision]), $MachinePrecision], N[(N[(-1.0 + x), $MachinePrecision] / x), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{x + 1} + \frac{-1}{x}\\
\mathbf{if}\;t\_0 \leq -2000000000:\\
\;\;\;\;1 + \frac{-1}{x}\\
\mathbf{elif}\;t\_0 \leq 0:\\
\;\;\;\;\frac{-1}{x \cdot x}\\
\mathbf{else}:\\
\;\;\;\;\frac{-1 + x}{x}\\
\end{array}
\end{array}
if (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) < -2e9Initial program 100.0%
Taylor expanded in x around 0
Simplified100.0%
if -2e9 < (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) < 0.0Initial program 60.4%
Taylor expanded in x around inf
/-lowering-/.f64N/A
+-rgt-identityN/A
unpow2N/A
accelerator-lowering-fma.f6495.9
Simplified95.9%
+-rgt-identityN/A
*-lowering-*.f6495.9
Applied egg-rr95.9%
if 0.0 < (-.f64 (/.f64 #s(literal 1 binary64) (+.f64 x #s(literal 1 binary64))) (/.f64 #s(literal 1 binary64) x)) Initial program 100.0%
frac-subN/A
div-subN/A
sub-negN/A
*-lft-identityN/A
div-invN/A
metadata-evalN/A
frac-timesN/A
accelerator-lowering-fma.f64N/A
frac-timesN/A
metadata-evalN/A
/-lowering-/.f64N/A
distribute-lft1-inN/A
accelerator-lowering-fma.f64N/A
neg-lowering-neg.f64N/A
metadata-evalN/A
div-invN/A
/-lowering-/.f64N/A
Applied egg-rr100.0%
Applied egg-rr100.0%
distribute-lft1-inN/A
metadata-evalN/A
sub-negN/A
associate-/r*N/A
/-lowering-/.f64N/A
associate--r+N/A
+-inversesN/A
metadata-evalN/A
metadata-evalN/A
/-lowering-/.f64N/A
sub-negN/A
metadata-evalN/A
+-lowering-+.f64100.0
Applied egg-rr100.0%
Taylor expanded in x around 0
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f6498.2
Simplified98.2%
Final simplification97.6%
(FPCore (x) :precision binary64 (/ -1.0 (fma x x x)))
double code(double x) {
return -1.0 / fma(x, x, x);
}
function code(x) return Float64(-1.0 / fma(x, x, x)) end
code[x_] := N[(-1.0 / N[(x * x + x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{\mathsf{fma}\left(x, x, x\right)}
\end{array}
Initial program 81.4%
frac-subN/A
div-subN/A
sub-negN/A
*-lft-identityN/A
div-invN/A
metadata-evalN/A
frac-timesN/A
accelerator-lowering-fma.f64N/A
frac-timesN/A
metadata-evalN/A
/-lowering-/.f64N/A
distribute-lft1-inN/A
accelerator-lowering-fma.f64N/A
neg-lowering-neg.f64N/A
metadata-evalN/A
div-invN/A
/-lowering-/.f64N/A
Applied egg-rr81.4%
Applied egg-rr83.0%
associate--r+N/A
+-inversesN/A
metadata-evalN/A
metadata-eval99.2
Applied egg-rr99.2%
(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 81.4%
Taylor expanded in x around 0
/-lowering-/.f6454.5
Simplified54.5%
(FPCore (x) :precision binary64 (- 0.0 x))
double code(double x) {
return 0.0 - x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.0d0 - x
end function
public static double code(double x) {
return 0.0 - x;
}
def code(x): return 0.0 - x
function code(x) return Float64(0.0 - x) end
function tmp = code(x) tmp = 0.0 - x; end
code[x_] := N[(0.0 - x), $MachinePrecision]
\begin{array}{l}
\\
0 - x
\end{array}
Initial program 81.4%
Taylor expanded in x around 0
mul-1-negN/A
unsub-negN/A
--lowering--.f6454.1
Simplified54.1%
Taylor expanded in x around inf
mul-1-negN/A
neg-sub0N/A
--lowering--.f643.1
Simplified3.1%
sub0-negN/A
neg-lowering-neg.f643.1
Applied egg-rr3.1%
Final simplification3.1%
(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 81.4%
Taylor expanded in x around 0
div-subN/A
sub-negN/A
*-commutativeN/A
associate-/l*N/A
*-inversesN/A
*-rgt-identityN/A
+-commutativeN/A
associate-+l+N/A
+-commutativeN/A
neg-sub0N/A
associate-+l-N/A
neg-sub0N/A
mul-1-negN/A
accelerator-lowering-fma.f64N/A
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f64N/A
mul-1-negN/A
neg-sub0N/A
associate-+l-N/A
neg-sub0N/A
+-commutativeN/A
+-lowering-+.f64N/A
distribute-neg-fracN/A
metadata-evalN/A
/-lowering-/.f6453.8
Simplified53.8%
Taylor expanded in x around inf
sub-negN/A
distribute-rgt-inN/A
unpow2N/A
associate-*r*N/A
distribute-lft-neg-outN/A
lft-mult-inverseN/A
metadata-evalN/A
+-commutativeN/A
+-commutativeN/A
distribute-rgt1-inN/A
lft-mult-inverseN/A
associate-+r+N/A
Simplified2.5%
Taylor expanded in x around 0
Simplified3.1%
(FPCore (x) :precision binary64 (/ (/ -1.0 x) (+ x 1.0)))
double code(double x) {
return (-1.0 / x) / (x + 1.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-1.0d0) / x) / (x + 1.0d0)
end function
public static double code(double x) {
return (-1.0 / x) / (x + 1.0);
}
def code(x): return (-1.0 / x) / (x + 1.0)
function code(x) return Float64(Float64(-1.0 / x) / Float64(x + 1.0)) end
function tmp = code(x) tmp = (-1.0 / x) / (x + 1.0); end
code[x_] := N[(N[(-1.0 / x), $MachinePrecision] / N[(x + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-1}{x}}{x + 1}
\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(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}
herbie shell --seed 2024194
(FPCore (x)
:name "2frac (problem 3.3.1)"
:precision binary64
:alt
(! :herbie-platform default (/ (/ -1 x) (+ x 1)))
:alt
(! :herbie-platform default (/ 1 (* x (- -1 x))))
(- (/ 1.0 (+ x 1.0)) (/ 1.0 x)))