
(FPCore (c x y) :precision binary64 (* c (log (+ 1.0 (* (- (pow (E) x) 1.0) y)))))
\begin{array}{l}
\\
c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (c x y) :precision binary64 (* c (log (+ 1.0 (* (- (pow (E) x) 1.0) y)))))
\begin{array}{l}
\\
c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)
\end{array}
(FPCore (c x y) :precision binary64 (if (or (<= y -116000.0) (not (<= y 1.52e-148))) (* (log1p (* y (expm1 x))) c) (* (* (expm1 x) c) y)))
double code(double c, double x, double y) {
double tmp;
if ((y <= -116000.0) || !(y <= 1.52e-148)) {
tmp = log1p((y * expm1(x))) * c;
} else {
tmp = (expm1(x) * c) * y;
}
return tmp;
}
public static double code(double c, double x, double y) {
double tmp;
if ((y <= -116000.0) || !(y <= 1.52e-148)) {
tmp = Math.log1p((y * Math.expm1(x))) * c;
} else {
tmp = (Math.expm1(x) * c) * y;
}
return tmp;
}
def code(c, x, y): tmp = 0 if (y <= -116000.0) or not (y <= 1.52e-148): tmp = math.log1p((y * math.expm1(x))) * c else: tmp = (math.expm1(x) * c) * y return tmp
function code(c, x, y) tmp = 0.0 if ((y <= -116000.0) || !(y <= 1.52e-148)) tmp = Float64(log1p(Float64(y * expm1(x))) * c); else tmp = Float64(Float64(expm1(x) * c) * y); end return tmp end
code[c_, x_, y_] := If[Or[LessEqual[y, -116000.0], N[Not[LessEqual[y, 1.52e-148]], $MachinePrecision]], N[(N[Log[1 + N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -116000 \lor \neg \left(y \leq 1.52 \cdot 10^{-148}\right):\\
\;\;\;\;\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c\\
\mathbf{else}:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot c\right) \cdot y\\
\end{array}
\end{array}
if y < -116000 or 1.52000000000000002e-148 < y Initial program 36.3%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6436.3
Applied rewrites99.7%
if -116000 < y < 1.52000000000000002e-148Initial program 51.3%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6451.3
Applied rewrites90.5%
Taylor expanded in y around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-expm1.f6499.9
Applied rewrites99.9%
Final simplification99.8%
(FPCore (c x y) :precision binary64 (if (or (<= y -3.6e+20) (not (<= y 7400000.0))) (* (log1p (* y (* (fma 0.5 x 1.0) x))) c) (* (* (expm1 x) c) y)))
double code(double c, double x, double y) {
double tmp;
if ((y <= -3.6e+20) || !(y <= 7400000.0)) {
tmp = log1p((y * (fma(0.5, x, 1.0) * x))) * c;
} else {
tmp = (expm1(x) * c) * y;
}
return tmp;
}
function code(c, x, y) tmp = 0.0 if ((y <= -3.6e+20) || !(y <= 7400000.0)) tmp = Float64(log1p(Float64(y * Float64(fma(0.5, x, 1.0) * x))) * c); else tmp = Float64(Float64(expm1(x) * c) * y); end return tmp end
code[c_, x_, y_] := If[Or[LessEqual[y, -3.6e+20], N[Not[LessEqual[y, 7400000.0]], $MachinePrecision]], N[(N[Log[1 + N[(y * N[(N[(0.5 * x + 1.0), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -3.6 \cdot 10^{+20} \lor \neg \left(y \leq 7400000\right):\\
\;\;\;\;\mathsf{log1p}\left(y \cdot \left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right)\right) \cdot c\\
\mathbf{else}:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot c\right) \cdot y\\
\end{array}
\end{array}
if y < -3.6e20 or 7.4e6 < y Initial program 36.4%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6436.4
Applied rewrites99.7%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
lower-fma.f6474.1
Applied rewrites74.1%
if -3.6e20 < y < 7.4e6Initial program 48.1%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6448.1
Applied rewrites92.5%
Taylor expanded in y around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-expm1.f6497.9
Applied rewrites97.9%
Final simplification88.5%
(FPCore (c x y) :precision binary64 (if (or (<= y -1.2e+144) (not (<= y 1e+186))) (* c (log (fma y x 1.0))) (* (* (expm1 x) c) y)))
double code(double c, double x, double y) {
double tmp;
if ((y <= -1.2e+144) || !(y <= 1e+186)) {
tmp = c * log(fma(y, x, 1.0));
} else {
tmp = (expm1(x) * c) * y;
}
return tmp;
}
function code(c, x, y) tmp = 0.0 if ((y <= -1.2e+144) || !(y <= 1e+186)) tmp = Float64(c * log(fma(y, x, 1.0))); else tmp = Float64(Float64(expm1(x) * c) * y); end return tmp end
code[c_, x_, y_] := If[Or[LessEqual[y, -1.2e+144], N[Not[LessEqual[y, 1e+186]], $MachinePrecision]], N[(c * N[Log[N[(y * x + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.2 \cdot 10^{+144} \lor \neg \left(y \leq 10^{+186}\right):\\
\;\;\;\;c \cdot \log \left(\mathsf{fma}\left(y, x, 1\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot c\right) \cdot y\\
\end{array}
\end{array}
if y < -1.2e144 or 9.9999999999999998e185 < y Initial program 39.6%
Taylor expanded in x around 0
+-commutativeN/A
log-EN/A
metadata-evalN/A
log-EN/A
associate-*r*N/A
log-EN/A
metadata-evalN/A
*-rgt-identityN/A
*-commutativeN/A
lower-fma.f6456.0
Applied rewrites56.0%
if -1.2e144 < y < 9.9999999999999998e185Initial program 44.3%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6444.3
Applied rewrites94.3%
Taylor expanded in y around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-expm1.f6488.2
Applied rewrites88.2%
Final simplification82.2%
(FPCore (c x y) :precision binary64 (if (<= y 7400000.0) (* (* (expm1 x) c) y) (* c (* y x))))
double code(double c, double x, double y) {
double tmp;
if (y <= 7400000.0) {
tmp = (expm1(x) * c) * y;
} else {
tmp = c * (y * x);
}
return tmp;
}
public static double code(double c, double x, double y) {
double tmp;
if (y <= 7400000.0) {
tmp = (Math.expm1(x) * c) * y;
} else {
tmp = c * (y * x);
}
return tmp;
}
def code(c, x, y): tmp = 0 if y <= 7400000.0: tmp = (math.expm1(x) * c) * y else: tmp = c * (y * x) return tmp
function code(c, x, y) tmp = 0.0 if (y <= 7400000.0) tmp = Float64(Float64(expm1(x) * c) * y); else tmp = Float64(c * Float64(y * x)); end return tmp end
code[c_, x_, y_] := If[LessEqual[y, 7400000.0], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision], N[(c * N[(y * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 7400000:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot c\right) \cdot y\\
\mathbf{else}:\\
\;\;\;\;c \cdot \left(y \cdot x\right)\\
\end{array}
\end{array}
if y < 7.4e6Initial program 48.9%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6448.9
Applied rewrites94.6%
Taylor expanded in y around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-expm1.f6478.6
Applied rewrites78.6%
if 7.4e6 < y Initial program 10.2%
Taylor expanded in x around 0
log-EN/A
metadata-evalN/A
log-EN/A
associate-*r*N/A
log-EN/A
metadata-evalN/A
*-rgt-identityN/A
*-commutativeN/A
lower-*.f6457.9
Applied rewrites57.9%
(FPCore (c x y) :precision binary64 (if (<= c 0.027) (* (* c y) x) (* (* (* (fma (fma 0.16666666666666666 x 0.5) x 1.0) x) c) y)))
double code(double c, double x, double y) {
double tmp;
if (c <= 0.027) {
tmp = (c * y) * x;
} else {
tmp = ((fma(fma(0.16666666666666666, x, 0.5), x, 1.0) * x) * c) * y;
}
return tmp;
}
function code(c, x, y) tmp = 0.0 if (c <= 0.027) tmp = Float64(Float64(c * y) * x); else tmp = Float64(Float64(Float64(fma(fma(0.16666666666666666, x, 0.5), x, 1.0) * x) * c) * y); end return tmp end
code[c_, x_, y_] := If[LessEqual[c, 0.027], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(N[(N[(N[(0.16666666666666666 * x + 0.5), $MachinePrecision] * x + 1.0), $MachinePrecision] * x), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;c \leq 0.027:\\
\;\;\;\;\left(c \cdot y\right) \cdot x\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot c\right) \cdot y\\
\end{array}
\end{array}
if c < 0.0269999999999999997Initial program 47.5%
Taylor expanded in x around 0
associate-*r*N/A
log-EN/A
*-rgt-identityN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-rgt-identityN/A
metadata-evalN/A
log-EN/A
log-EN/A
metadata-evalN/A
log-EN/A
lower-*.f64N/A
log-EN/A
*-rgt-identityN/A
lower-*.f6461.6
Applied rewrites61.6%
if 0.0269999999999999997 < c Initial program 28.2%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6428.2
Applied rewrites94.9%
Taylor expanded in y around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-expm1.f6474.6
Applied rewrites74.6%
Taylor expanded in x around 0
Applied rewrites59.4%
(FPCore (c x y) :precision binary64 (if (<= c 1e-13) (* (* c y) x) (* (* x c) y)))
double code(double c, double x, double y) {
double tmp;
if (c <= 1e-13) {
tmp = (c * y) * x;
} else {
tmp = (x * c) * 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(c, x, y)
use fmin_fmax_functions
real(8), intent (in) :: c
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (c <= 1d-13) then
tmp = (c * y) * x
else
tmp = (x * c) * y
end if
code = tmp
end function
public static double code(double c, double x, double y) {
double tmp;
if (c <= 1e-13) {
tmp = (c * y) * x;
} else {
tmp = (x * c) * y;
}
return tmp;
}
def code(c, x, y): tmp = 0 if c <= 1e-13: tmp = (c * y) * x else: tmp = (x * c) * y return tmp
function code(c, x, y) tmp = 0.0 if (c <= 1e-13) tmp = Float64(Float64(c * y) * x); else tmp = Float64(Float64(x * c) * y); end return tmp end
function tmp_2 = code(c, x, y) tmp = 0.0; if (c <= 1e-13) tmp = (c * y) * x; else tmp = (x * c) * y; end tmp_2 = tmp; end
code[c_, x_, y_] := If[LessEqual[c, 1e-13], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(x * c), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;c \leq 10^{-13}:\\
\;\;\;\;\left(c \cdot y\right) \cdot x\\
\mathbf{else}:\\
\;\;\;\;\left(x \cdot c\right) \cdot y\\
\end{array}
\end{array}
if c < 1e-13Initial program 47.3%
Taylor expanded in x around 0
associate-*r*N/A
log-EN/A
*-rgt-identityN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-rgt-identityN/A
metadata-evalN/A
log-EN/A
log-EN/A
metadata-evalN/A
log-EN/A
lower-*.f64N/A
log-EN/A
*-rgt-identityN/A
lower-*.f6461.9
Applied rewrites61.9%
if 1e-13 < c Initial program 29.5%
Taylor expanded in x around 0
associate-*r*N/A
log-EN/A
*-rgt-identityN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-rgt-identityN/A
metadata-evalN/A
log-EN/A
log-EN/A
metadata-evalN/A
log-EN/A
lower-*.f64N/A
log-EN/A
*-rgt-identityN/A
lower-*.f6451.5
Applied rewrites51.5%
Applied rewrites58.4%
(FPCore (c x y) :precision binary64 (* (* c y) x))
double code(double c, double x, double y) {
return (c * y) * 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(c, x, y)
use fmin_fmax_functions
real(8), intent (in) :: c
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (c * y) * x
end function
public static double code(double c, double x, double y) {
return (c * y) * x;
}
def code(c, x, y): return (c * y) * x
function code(c, x, y) return Float64(Float64(c * y) * x) end
function tmp = code(c, x, y) tmp = (c * y) * x; end
code[c_, x_, y_] := N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}
\\
\left(c \cdot y\right) \cdot x
\end{array}
Initial program 43.4%
Taylor expanded in x around 0
associate-*r*N/A
log-EN/A
*-rgt-identityN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-rgt-identityN/A
metadata-evalN/A
log-EN/A
log-EN/A
metadata-evalN/A
log-EN/A
lower-*.f64N/A
log-EN/A
*-rgt-identityN/A
lower-*.f6459.7
Applied rewrites59.7%
(FPCore (c x y) :precision binary64 (* c (log1p (* (expm1 x) y))))
double code(double c, double x, double y) {
return c * log1p((expm1(x) * y));
}
public static double code(double c, double x, double y) {
return c * Math.log1p((Math.expm1(x) * y));
}
def code(c, x, y): return c * math.log1p((math.expm1(x) * y))
function code(c, x, y) return Float64(c * log1p(Float64(expm1(x) * y))) end
code[c_, x_, y_] := N[(c * N[Log[1 + N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right)
\end{array}
herbie shell --seed 2024346
(FPCore (c x y)
:name "Logarithmic Transform"
:precision binary64
:alt
(* c (log1p (* (expm1 x) y)))
(* c (log (+ 1.0 (* (- (pow (E) x) 1.0) y)))))