
(FPCore (x y) :precision binary64 (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))
double code(double x, double y) {
return 1.0 - log((1.0 - ((x - y) / (1.0 - y))));
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 - log((1.0d0 - ((x - y) / (1.0d0 - y))))
end function
public static double code(double x, double y) {
return 1.0 - Math.log((1.0 - ((x - y) / (1.0 - y))));
}
def code(x, y): return 1.0 - math.log((1.0 - ((x - y) / (1.0 - y))))
function code(x, y) return Float64(1.0 - log(Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))) end
function tmp = code(x, y) tmp = 1.0 - log((1.0 - ((x - y) / (1.0 - y)))); end
code[x_, y_] := N[(1.0 - N[Log[N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1 - \log \left(1 - \frac{x - y}{1 - y}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))
double code(double x, double y) {
return 1.0 - log((1.0 - ((x - y) / (1.0 - y))));
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 - log((1.0d0 - ((x - y) / (1.0d0 - y))))
end function
public static double code(double x, double y) {
return 1.0 - Math.log((1.0 - ((x - y) / (1.0 - y))));
}
def code(x, y): return 1.0 - math.log((1.0 - ((x - y) / (1.0 - y))))
function code(x, y) return Float64(1.0 - log(Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))) end
function tmp = code(x, y) tmp = 1.0 - log((1.0 - ((x - y) / (1.0 - y)))); end
code[x_, y_] := N[(1.0 - N[Log[N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1 - \log \left(1 - \frac{x - y}{1 - y}\right)
\end{array}
(FPCore (x y)
:precision binary64
(let* ((t_0 (- 1.0 (/ (- x y) (- 1.0 y)))))
(if (<= (- 1.0 (log t_0)) 2.0)
(log (/ (E) t_0))
(- 1.0 (log (/ (+ (+ -1.0 (/ (- x 1.0) y)) x) y))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 - \frac{x - y}{1 - y}\\
\mathbf{if}\;1 - \log t\_0 \leq 2:\\
\;\;\;\;\log \left(\frac{\mathsf{E}\left(\right)}{t\_0}\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{\left(-1 + \frac{x - 1}{y}\right) + x}{y}\right)\\
\end{array}
\end{array}
if (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < 2Initial program 100.0%
add-log-expN/A
lower-log.f64N/A
lift--.f64N/A
exp-diffN/A
lift-log.f64N/A
add-exp-logN/A
lower-/.f64N/A
exp-1-eN/A
lower-E.f64100.0
Applied rewrites100.0%
if 2 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) Initial program 6.9%
Taylor expanded in y around -inf
Applied rewrites100.0%
Final simplification100.0%
(FPCore (x y)
:precision binary64
(let* ((t_0 (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y)))))))
(if (<= t_0 -20.0)
(- 1.0 (log (/ x (+ -1.0 y))))
(if (<= t_0 2.0)
(- 1.0 (log (* (- y -1.0) (- 1.0 x))))
(- 1.0 (log (/ (+ -1.0 x) y)))))))
double code(double x, double y) {
double t_0 = 1.0 - log((1.0 - ((x - y) / (1.0 - y))));
double tmp;
if (t_0 <= -20.0) {
tmp = 1.0 - log((x / (-1.0 + y)));
} else if (t_0 <= 2.0) {
tmp = 1.0 - log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - log(((-1.0 + x) / y));
}
return tmp;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = 1.0d0 - log((1.0d0 - ((x - y) / (1.0d0 - y))))
if (t_0 <= (-20.0d0)) then
tmp = 1.0d0 - log((x / ((-1.0d0) + y)))
else if (t_0 <= 2.0d0) then
tmp = 1.0d0 - log(((y - (-1.0d0)) * (1.0d0 - x)))
else
tmp = 1.0d0 - log((((-1.0d0) + x) / y))
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = 1.0 - Math.log((1.0 - ((x - y) / (1.0 - y))));
double tmp;
if (t_0 <= -20.0) {
tmp = 1.0 - Math.log((x / (-1.0 + y)));
} else if (t_0 <= 2.0) {
tmp = 1.0 - Math.log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - Math.log(((-1.0 + x) / y));
}
return tmp;
}
def code(x, y): t_0 = 1.0 - math.log((1.0 - ((x - y) / (1.0 - y)))) tmp = 0 if t_0 <= -20.0: tmp = 1.0 - math.log((x / (-1.0 + y))) elif t_0 <= 2.0: tmp = 1.0 - math.log(((y - -1.0) * (1.0 - x))) else: tmp = 1.0 - math.log(((-1.0 + x) / y)) return tmp
function code(x, y) t_0 = Float64(1.0 - log(Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))) tmp = 0.0 if (t_0 <= -20.0) tmp = Float64(1.0 - log(Float64(x / Float64(-1.0 + y)))); elseif (t_0 <= 2.0) tmp = Float64(1.0 - log(Float64(Float64(y - -1.0) * Float64(1.0 - x)))); else tmp = Float64(1.0 - log(Float64(Float64(-1.0 + x) / y))); end return tmp end
function tmp_2 = code(x, y) t_0 = 1.0 - log((1.0 - ((x - y) / (1.0 - y)))); tmp = 0.0; if (t_0 <= -20.0) tmp = 1.0 - log((x / (-1.0 + y))); elseif (t_0 <= 2.0) tmp = 1.0 - log(((y - -1.0) * (1.0 - x))); else tmp = 1.0 - log(((-1.0 + x) / y)); end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[Log[N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -20.0], N[(1.0 - N[Log[N[(x / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 2.0], N[(1.0 - N[Log[N[(N[(y - -1.0), $MachinePrecision] * N[(1.0 - x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(-1.0 + x), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 - \log \left(1 - \frac{x - y}{1 - y}\right)\\
\mathbf{if}\;t\_0 \leq -20:\\
\;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\
\mathbf{elif}\;t\_0 \leq 2:\\
\;\;\;\;1 - \log \left(\left(y - -1\right) \cdot \left(1 - x\right)\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{-1 + x}{y}\right)\\
\end{array}
\end{array}
if (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < -20Initial program 100.0%
Taylor expanded in x around inf
Applied rewrites100.0%
if -20 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < 2Initial program 99.9%
Taylor expanded in y around 0
Applied rewrites99.1%
if 2 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) Initial program 6.9%
Taylor expanded in y around inf
Applied rewrites100.0%
Final simplification99.6%
(FPCore (x y)
:precision binary64
(let* ((t_0 (- 1.0 (/ (- x y) (- 1.0 y)))))
(if (<= (- 1.0 (log t_0)) 2.0)
(log (/ (E) t_0))
(- 1.0 (log (/ (+ -1.0 x) y))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 - \frac{x - y}{1 - y}\\
\mathbf{if}\;1 - \log t\_0 \leq 2:\\
\;\;\;\;\log \left(\frac{\mathsf{E}\left(\right)}{t\_0}\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{-1 + x}{y}\right)\\
\end{array}
\end{array}
if (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < 2Initial program 100.0%
add-log-expN/A
lower-log.f64N/A
lift--.f64N/A
exp-diffN/A
lift-log.f64N/A
add-exp-logN/A
lower-/.f64N/A
exp-1-eN/A
lower-E.f64100.0
Applied rewrites100.0%
if 2 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) Initial program 6.9%
Taylor expanded in y around inf
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (let* ((t_0 (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))) (if (<= t_0 2.0) t_0 (- 1.0 (log (/ (+ -1.0 x) y))))))
double code(double x, double y) {
double t_0 = 1.0 - log((1.0 - ((x - y) / (1.0 - y))));
double tmp;
if (t_0 <= 2.0) {
tmp = t_0;
} else {
tmp = 1.0 - log(((-1.0 + x) / y));
}
return tmp;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = 1.0d0 - log((1.0d0 - ((x - y) / (1.0d0 - y))))
if (t_0 <= 2.0d0) then
tmp = t_0
else
tmp = 1.0d0 - log((((-1.0d0) + x) / y))
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = 1.0 - Math.log((1.0 - ((x - y) / (1.0 - y))));
double tmp;
if (t_0 <= 2.0) {
tmp = t_0;
} else {
tmp = 1.0 - Math.log(((-1.0 + x) / y));
}
return tmp;
}
def code(x, y): t_0 = 1.0 - math.log((1.0 - ((x - y) / (1.0 - y)))) tmp = 0 if t_0 <= 2.0: tmp = t_0 else: tmp = 1.0 - math.log(((-1.0 + x) / y)) return tmp
function code(x, y) t_0 = Float64(1.0 - log(Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))) tmp = 0.0 if (t_0 <= 2.0) tmp = t_0; else tmp = Float64(1.0 - log(Float64(Float64(-1.0 + x) / y))); end return tmp end
function tmp_2 = code(x, y) t_0 = 1.0 - log((1.0 - ((x - y) / (1.0 - y)))); tmp = 0.0; if (t_0 <= 2.0) tmp = t_0; else tmp = 1.0 - log(((-1.0 + x) / y)); end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[Log[N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 2.0], t$95$0, N[(1.0 - N[Log[N[(N[(-1.0 + x), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 - \log \left(1 - \frac{x - y}{1 - y}\right)\\
\mathbf{if}\;t\_0 \leq 2:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{-1 + x}{y}\right)\\
\end{array}
\end{array}
if (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < 2Initial program 100.0%
if 2 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) Initial program 6.9%
Taylor expanded in y around inf
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (if (<= (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))) 2.0) (- 1.0 (log1p (- x))) (- 1.0 (log (/ -1.0 y)))))
double code(double x, double y) {
double tmp;
if ((1.0 - log((1.0 - ((x - y) / (1.0 - y))))) <= 2.0) {
tmp = 1.0 - log1p(-x);
} else {
tmp = 1.0 - log((-1.0 / y));
}
return tmp;
}
public static double code(double x, double y) {
double tmp;
if ((1.0 - Math.log((1.0 - ((x - y) / (1.0 - y))))) <= 2.0) {
tmp = 1.0 - Math.log1p(-x);
} else {
tmp = 1.0 - Math.log((-1.0 / y));
}
return tmp;
}
def code(x, y): tmp = 0 if (1.0 - math.log((1.0 - ((x - y) / (1.0 - y))))) <= 2.0: tmp = 1.0 - math.log1p(-x) else: tmp = 1.0 - math.log((-1.0 / y)) return tmp
function code(x, y) tmp = 0.0 if (Float64(1.0 - log(Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))) <= 2.0) tmp = Float64(1.0 - log1p(Float64(-x))); else tmp = Float64(1.0 - log(Float64(-1.0 / y))); end return tmp end
code[x_, y_] := If[LessEqual[N[(1.0 - N[Log[N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 2.0], N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - \log \left(1 - \frac{x - y}{1 - y}\right) \leq 2:\\
\;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\
\end{array}
\end{array}
if (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) < 2Initial program 100.0%
Taylor expanded in y around 0
Applied rewrites87.3%
if 2 < (-.f64 #s(literal 1 binary64) (log.f64 (-.f64 #s(literal 1 binary64) (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))))) Initial program 6.9%
Taylor expanded in y around inf
Applied rewrites100.0%
Taylor expanded in x around 0
Applied rewrites73.5%
(FPCore (x y)
:precision binary64
(if (<= y -0.82)
(- 1.0 (log (/ (+ -1.0 x) y)))
(if (<= y 1.0)
(- 1.0 (log (* (- y -1.0) (- 1.0 x))))
(- 1.0 (log (/ x y))))))
double code(double x, double y) {
double tmp;
if (y <= -0.82) {
tmp = 1.0 - log(((-1.0 + x) / y));
} else if (y <= 1.0) {
tmp = 1.0 - log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - log((x / y));
}
return tmp;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-0.82d0)) then
tmp = 1.0d0 - log((((-1.0d0) + x) / y))
else if (y <= 1.0d0) then
tmp = 1.0d0 - log(((y - (-1.0d0)) * (1.0d0 - x)))
else
tmp = 1.0d0 - log((x / y))
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -0.82) {
tmp = 1.0 - Math.log(((-1.0 + x) / y));
} else if (y <= 1.0) {
tmp = 1.0 - Math.log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - Math.log((x / y));
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -0.82: tmp = 1.0 - math.log(((-1.0 + x) / y)) elif y <= 1.0: tmp = 1.0 - math.log(((y - -1.0) * (1.0 - x))) else: tmp = 1.0 - math.log((x / y)) return tmp
function code(x, y) tmp = 0.0 if (y <= -0.82) tmp = Float64(1.0 - log(Float64(Float64(-1.0 + x) / y))); elseif (y <= 1.0) tmp = Float64(1.0 - log(Float64(Float64(y - -1.0) * Float64(1.0 - x)))); else tmp = Float64(1.0 - log(Float64(x / y))); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -0.82) tmp = 1.0 - log(((-1.0 + x) / y)); elseif (y <= 1.0) tmp = 1.0 - log(((y - -1.0) * (1.0 - x))); else tmp = 1.0 - log((x / y)); end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -0.82], N[(1.0 - N[Log[N[(N[(-1.0 + x), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(1.0 - N[Log[N[(N[(y - -1.0), $MachinePrecision] * N[(1.0 - x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -0.82:\\
\;\;\;\;1 - \log \left(\frac{-1 + x}{y}\right)\\
\mathbf{elif}\;y \leq 1:\\
\;\;\;\;1 - \log \left(\left(y - -1\right) \cdot \left(1 - x\right)\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{x}{y}\right)\\
\end{array}
\end{array}
if y < -0.819999999999999951Initial program 18.6%
Taylor expanded in y around inf
Applied rewrites99.8%
if -0.819999999999999951 < y < 1Initial program 99.9%
Taylor expanded in y around 0
Applied rewrites99.4%
if 1 < y Initial program 49.4%
Taylor expanded in y around inf
Applied rewrites97.9%
Taylor expanded in x around inf
Applied rewrites97.9%
Final simplification99.4%
(FPCore (x y)
:precision binary64
(if (<= y -1.0)
(- 1.0 (log (/ -1.0 y)))
(if (<= y 1.0)
(- 1.0 (log (* (- y -1.0) (- 1.0 x))))
(- 1.0 (log (/ x y))))))
double code(double x, double y) {
double tmp;
if (y <= -1.0) {
tmp = 1.0 - log((-1.0 / y));
} else if (y <= 1.0) {
tmp = 1.0 - log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - log((x / y));
}
return tmp;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-1.0d0)) then
tmp = 1.0d0 - log(((-1.0d0) / y))
else if (y <= 1.0d0) then
tmp = 1.0d0 - log(((y - (-1.0d0)) * (1.0d0 - x)))
else
tmp = 1.0d0 - log((x / y))
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -1.0) {
tmp = 1.0 - Math.log((-1.0 / y));
} else if (y <= 1.0) {
tmp = 1.0 - Math.log(((y - -1.0) * (1.0 - x)));
} else {
tmp = 1.0 - Math.log((x / y));
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -1.0: tmp = 1.0 - math.log((-1.0 / y)) elif y <= 1.0: tmp = 1.0 - math.log(((y - -1.0) * (1.0 - x))) else: tmp = 1.0 - math.log((x / y)) return tmp
function code(x, y) tmp = 0.0 if (y <= -1.0) tmp = Float64(1.0 - log(Float64(-1.0 / y))); elseif (y <= 1.0) tmp = Float64(1.0 - log(Float64(Float64(y - -1.0) * Float64(1.0 - x)))); else tmp = Float64(1.0 - log(Float64(x / y))); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -1.0) tmp = 1.0 - log((-1.0 / y)); elseif (y <= 1.0) tmp = 1.0 - log(((y - -1.0) * (1.0 - x))); else tmp = 1.0 - log((x / y)); end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -1.0], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(1.0 - N[Log[N[(N[(y - -1.0), $MachinePrecision] * N[(1.0 - x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1:\\
\;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\
\mathbf{elif}\;y \leq 1:\\
\;\;\;\;1 - \log \left(\left(y - -1\right) \cdot \left(1 - x\right)\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{x}{y}\right)\\
\end{array}
\end{array}
if y < -1Initial program 18.6%
Taylor expanded in y around inf
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites77.5%
if -1 < y < 1Initial program 99.9%
Taylor expanded in y around 0
Applied rewrites99.4%
if 1 < y Initial program 49.4%
Taylor expanded in y around inf
Applied rewrites97.9%
Taylor expanded in x around inf
Applied rewrites97.9%
Final simplification92.7%
(FPCore (x y) :precision binary64 (if (<= y -130000000000.0) (- 1.0 (log (/ -1.0 y))) (if (<= y 1.0) (- 1.0 (log1p (- x))) (- 1.0 (log (/ x y))))))
double code(double x, double y) {
double tmp;
if (y <= -130000000000.0) {
tmp = 1.0 - log((-1.0 / y));
} else if (y <= 1.0) {
tmp = 1.0 - log1p(-x);
} else {
tmp = 1.0 - log((x / y));
}
return tmp;
}
public static double code(double x, double y) {
double tmp;
if (y <= -130000000000.0) {
tmp = 1.0 - Math.log((-1.0 / y));
} else if (y <= 1.0) {
tmp = 1.0 - Math.log1p(-x);
} else {
tmp = 1.0 - Math.log((x / y));
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -130000000000.0: tmp = 1.0 - math.log((-1.0 / y)) elif y <= 1.0: tmp = 1.0 - math.log1p(-x) else: tmp = 1.0 - math.log((x / y)) return tmp
function code(x, y) tmp = 0.0 if (y <= -130000000000.0) tmp = Float64(1.0 - log(Float64(-1.0 / y))); elseif (y <= 1.0) tmp = Float64(1.0 - log1p(Float64(-x))); else tmp = Float64(1.0 - log(Float64(x / y))); end return tmp end
code[x_, y_] := If[LessEqual[y, -130000000000.0], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -130000000000:\\
\;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\
\mathbf{elif}\;y \leq 1:\\
\;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\
\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{x}{y}\right)\\
\end{array}
\end{array}
if y < -1.3e11Initial program 17.5%
Taylor expanded in y around inf
Applied rewrites100.0%
Taylor expanded in x around 0
Applied rewrites78.5%
if -1.3e11 < y < 1Initial program 99.9%
Taylor expanded in y around 0
Applied rewrites97.3%
if 1 < y Initial program 49.4%
Taylor expanded in y around inf
Applied rewrites97.9%
Taylor expanded in x around inf
Applied rewrites97.9%
(FPCore (x y) :precision binary64 (- 1.0 (log1p (- x))))
double code(double x, double y) {
return 1.0 - log1p(-x);
}
public static double code(double x, double y) {
return 1.0 - Math.log1p(-x);
}
def code(x, y): return 1.0 - math.log1p(-x)
function code(x, y) return Float64(1.0 - log1p(Float64(-x))) end
code[x_, y_] := N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1 - \mathsf{log1p}\left(-x\right)
\end{array}
Initial program 70.9%
Taylor expanded in y around 0
Applied rewrites63.2%
(FPCore (x y) :precision binary64 (- 1.0 (- x)))
double code(double x, double y) {
return 1.0 - -x;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 - -x
end function
public static double code(double x, double y) {
return 1.0 - -x;
}
def code(x, y): return 1.0 - -x
function code(x, y) return Float64(1.0 - Float64(-x)) end
function tmp = code(x, y) tmp = 1.0 - -x; end
code[x_, y_] := N[(1.0 - (-x)), $MachinePrecision]
\begin{array}{l}
\\
1 - \left(-x\right)
\end{array}
Initial program 70.9%
Taylor expanded in y around 0
Applied rewrites63.2%
Taylor expanded in x around 0
Applied rewrites46.0%
(FPCore (x y)
:precision binary64
(let* ((t_0 (- 1.0 (log (- (/ x (* y y)) (- (/ 1.0 y) (/ x y)))))))
(if (< y -81284752.61947241)
t_0
(if (< y 3.0094271212461764e+25)
(log (/ (exp 1.0) (- 1.0 (/ (- x y) (- 1.0 y)))))
t_0))))
double code(double x, double y) {
double t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y))));
double tmp;
if (y < -81284752.61947241) {
tmp = t_0;
} else if (y < 3.0094271212461764e+25) {
tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
} else {
tmp = t_0;
}
return tmp;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(8) function code(x, y)
use fmin_fmax_functions
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = 1.0d0 - log(((x / (y * y)) - ((1.0d0 / y) - (x / y))))
if (y < (-81284752.61947241d0)) then
tmp = t_0
else if (y < 3.0094271212461764d+25) then
tmp = log((exp(1.0d0) / (1.0d0 - ((x - y) / (1.0d0 - y)))))
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = 1.0 - Math.log(((x / (y * y)) - ((1.0 / y) - (x / y))));
double tmp;
if (y < -81284752.61947241) {
tmp = t_0;
} else if (y < 3.0094271212461764e+25) {
tmp = Math.log((Math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = 1.0 - math.log(((x / (y * y)) - ((1.0 / y) - (x / y)))) tmp = 0 if y < -81284752.61947241: tmp = t_0 elif y < 3.0094271212461764e+25: tmp = math.log((math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y))))) else: tmp = t_0 return tmp
function code(x, y) t_0 = Float64(1.0 - log(Float64(Float64(x / Float64(y * y)) - Float64(Float64(1.0 / y) - Float64(x / y))))) tmp = 0.0 if (y < -81284752.61947241) tmp = t_0; elseif (y < 3.0094271212461764e+25) tmp = log(Float64(exp(1.0) / Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y))))); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y) t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y)))); tmp = 0.0; if (y < -81284752.61947241) tmp = t_0; elseif (y < 3.0094271212461764e+25) tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y))))); else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[Log[N[(N[(x / N[(y * y), $MachinePrecision]), $MachinePrecision] - N[(N[(1.0 / y), $MachinePrecision] - N[(x / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[Less[y, -81284752.61947241], t$95$0, If[Less[y, 3.0094271212461764e+25], N[Log[N[(N[Exp[1.0], $MachinePrecision] / N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 - \log \left(\frac{x}{y \cdot y} - \left(\frac{1}{y} - \frac{x}{y}\right)\right)\\
\mathbf{if}\;y < -81284752.61947241:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;y < 3.0094271212461764 \cdot 10^{+25}:\\
\;\;\;\;\log \left(\frac{e^{1}}{1 - \frac{x - y}{1 - y}}\right)\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
herbie shell --seed 2025021
(FPCore (x y)
:name "Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B"
:precision binary64
:alt
(! :herbie-platform default (if (< y -8128475261947241/100000000) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))) (if (< y 30094271212461764000000000) (log (/ (exp 1) (- 1 (/ (- x y) (- 1 y))))) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))))))
(- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))