
(FPCore (x) :precision binary64 (/ 10.0 (- 1.0 (* x x))))
double code(double x) {
return 10.0 / (1.0 - (x * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 10.0d0 / (1.0d0 - (x * x))
end function
public static double code(double x) {
return 10.0 / (1.0 - (x * x));
}
def code(x): return 10.0 / (1.0 - (x * x))
function code(x) return Float64(10.0 / Float64(1.0 - Float64(x * x))) end
function tmp = code(x) tmp = 10.0 / (1.0 - (x * x)); end
code[x_] := N[(10.0 / N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{10}{1 - x \cdot x}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (/ 10.0 (- 1.0 (* x x))))
double code(double x) {
return 10.0 / (1.0 - (x * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 10.0d0 / (1.0d0 - (x * x))
end function
public static double code(double x) {
return 10.0 / (1.0 - (x * x));
}
def code(x): return 10.0 / (1.0 - (x * x))
function code(x) return Float64(10.0 / Float64(1.0 - Float64(x * x))) end
function tmp = code(x) tmp = 10.0 / (1.0 - (x * x)); end
code[x_] := N[(10.0 / N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{10}{1 - x \cdot x}
\end{array}
(FPCore (x) :precision binary64 (/ -10.0 (fma x x -1.0)))
double code(double x) {
return -10.0 / fma(x, x, -1.0);
}
function code(x) return Float64(-10.0 / fma(x, x, -1.0)) end
code[x_] := N[(-10.0 / N[(x * x + -1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-10}{\mathsf{fma}\left(x, x, -1\right)}
\end{array}
Initial program 87.9%
sqr-neg87.9%
cancel-sign-sub87.9%
+-commutative87.9%
+-lft-identity87.9%
cancel-sign-sub87.9%
associate-+l-87.9%
sub0-neg87.9%
neg-mul-187.9%
associate-/r*87.9%
metadata-eval87.9%
sqr-neg87.9%
fma-neg99.6%
metadata-eval99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (x) :precision binary64 (/ 10.0 (- 1.0 (* x x))))
double code(double x) {
return 10.0 / (1.0 - (x * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 10.0d0 / (1.0d0 - (x * x))
end function
public static double code(double x) {
return 10.0 / (1.0 - (x * x));
}
def code(x): return 10.0 / (1.0 - (x * x))
function code(x) return Float64(10.0 / Float64(1.0 - Float64(x * x))) end
function tmp = code(x) tmp = 10.0 / (1.0 - (x * x)); end
code[x_] := N[(10.0 / N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{10}{1 - x \cdot x}
\end{array}
Initial program 87.9%
Final simplification87.9%
(FPCore (x) :precision binary64 (if (<= x 1.0) 10.0 -10.0))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 10.0;
} else {
tmp = -10.0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 1.0d0) then
tmp = 10.0d0
else
tmp = -10.0d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 10.0;
} else {
tmp = -10.0;
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.0: tmp = 10.0 else: tmp = -10.0 return tmp
function code(x) tmp = 0.0 if (x <= 1.0) tmp = 10.0; else tmp = -10.0; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 1.0) tmp = 10.0; else tmp = -10.0; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.0], 10.0, -10.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;10\\
\mathbf{else}:\\
\;\;\;\;-10\\
\end{array}
\end{array}
if x < 1Initial program 88.3%
sqr-neg88.3%
cancel-sign-sub88.3%
+-commutative88.3%
+-lft-identity88.3%
cancel-sign-sub88.3%
associate-+l-88.3%
sub0-neg88.3%
neg-mul-188.3%
associate-/r*88.3%
metadata-eval88.3%
sqr-neg88.3%
fma-neg99.6%
metadata-eval99.6%
Simplified99.6%
Taylor expanded in x around 0 13.5%
if 1 < x Initial program 87.1%
sqr-neg87.1%
cancel-sign-sub87.1%
+-commutative87.1%
+-lft-identity87.1%
cancel-sign-sub87.1%
associate-+l-87.1%
sub0-neg87.1%
neg-mul-187.1%
associate-/r*87.1%
metadata-eval87.1%
sqr-neg87.1%
fma-neg99.6%
metadata-eval99.6%
Simplified99.6%
frac-2neg99.6%
metadata-eval99.6%
div-inv99.4%
fma-udef87.1%
distribute-neg-in87.1%
metadata-eval87.1%
+-commutative87.1%
sub-neg87.1%
*-commutative87.1%
Applied egg-rr99.4%
add-sqr-sqrt0.0%
sqrt-unprod1.5%
frac-times1.5%
metadata-eval1.5%
pow21.5%
Applied egg-rr1.5%
Taylor expanded in x around 0 13.5%
Final simplification13.5%
(FPCore (x) :precision binary64 -10.0)
double code(double x) {
return -10.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = -10.0d0
end function
public static double code(double x) {
return -10.0;
}
def code(x): return -10.0
function code(x) return -10.0 end
function tmp = code(x) tmp = -10.0; end
code[x_] := -10.0
\begin{array}{l}
\\
-10
\end{array}
Initial program 87.9%
sqr-neg87.9%
cancel-sign-sub87.9%
+-commutative87.9%
+-lft-identity87.9%
cancel-sign-sub87.9%
associate-+l-87.9%
sub0-neg87.9%
neg-mul-187.9%
associate-/r*87.9%
metadata-eval87.9%
sqr-neg87.9%
fma-neg99.6%
metadata-eval99.6%
Simplified99.6%
frac-2neg99.6%
metadata-eval99.6%
div-inv99.4%
fma-udef87.9%
distribute-neg-in87.9%
metadata-eval87.9%
+-commutative87.9%
sub-neg87.9%
*-commutative87.9%
Applied egg-rr99.4%
add-sqr-sqrt67.2%
sqrt-unprod68.1%
frac-times68.0%
metadata-eval68.0%
pow268.0%
Applied egg-rr68.0%
Taylor expanded in x around 0 5.4%
Final simplification5.4%
herbie shell --seed 2024011
(FPCore (x)
:name "ENA, Section 1.4, Mentioned, B"
:precision binary64
:pre (and (<= 0.999 x) (<= x 1.001))
(/ 10.0 (- 1.0 (* x x))))