
(FPCore (c_p c_n t s)
:precision binary64
(let* ((t_1 (/ 1.0 (+ 1.0 (exp (- t))))) (t_2 (/ 1.0 (+ 1.0 (exp (- s))))))
(/
(* (pow t_2 c_p) (pow (- 1.0 t_2) c_n))
(* (pow t_1 c_p) (pow (- 1.0 t_1) c_n)))))
double code(double c_p, double c_n, double t, double s) {
double t_1 = 1.0 / (1.0 + exp(-t));
double t_2 = 1.0 / (1.0 + exp(-s));
return (pow(t_2, c_p) * pow((1.0 - t_2), c_n)) / (pow(t_1, c_p) * pow((1.0 - t_1), c_n));
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
real(8) :: t_1
real(8) :: t_2
t_1 = 1.0d0 / (1.0d0 + exp(-t))
t_2 = 1.0d0 / (1.0d0 + exp(-s))
code = ((t_2 ** c_p) * ((1.0d0 - t_2) ** c_n)) / ((t_1 ** c_p) * ((1.0d0 - t_1) ** c_n))
end function
public static double code(double c_p, double c_n, double t, double s) {
double t_1 = 1.0 / (1.0 + Math.exp(-t));
double t_2 = 1.0 / (1.0 + Math.exp(-s));
return (Math.pow(t_2, c_p) * Math.pow((1.0 - t_2), c_n)) / (Math.pow(t_1, c_p) * Math.pow((1.0 - t_1), c_n));
}
def code(c_p, c_n, t, s): t_1 = 1.0 / (1.0 + math.exp(-t)) t_2 = 1.0 / (1.0 + math.exp(-s)) return (math.pow(t_2, c_p) * math.pow((1.0 - t_2), c_n)) / (math.pow(t_1, c_p) * math.pow((1.0 - t_1), c_n))
function code(c_p, c_n, t, s) t_1 = Float64(1.0 / Float64(1.0 + exp(Float64(-t)))) t_2 = Float64(1.0 / Float64(1.0 + exp(Float64(-s)))) return Float64(Float64((t_2 ^ c_p) * (Float64(1.0 - t_2) ^ c_n)) / Float64((t_1 ^ c_p) * (Float64(1.0 - t_1) ^ c_n))) end
function tmp = code(c_p, c_n, t, s) t_1 = 1.0 / (1.0 + exp(-t)); t_2 = 1.0 / (1.0 + exp(-s)); tmp = ((t_2 ^ c_p) * ((1.0 - t_2) ^ c_n)) / ((t_1 ^ c_p) * ((1.0 - t_1) ^ c_n)); end
code[c$95$p_, c$95$n_, t_, s_] := Block[{t$95$1 = N[(1.0 / N[(1.0 + N[Exp[(-t)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / N[(1.0 + N[Exp[(-s)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Power[t$95$2, c$95$p], $MachinePrecision] * N[Power[N[(1.0 - t$95$2), $MachinePrecision], c$95$n], $MachinePrecision]), $MachinePrecision] / N[(N[Power[t$95$1, c$95$p], $MachinePrecision] * N[Power[N[(1.0 - t$95$1), $MachinePrecision], c$95$n], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \frac{1}{1 + e^{-t}}\\
t_2 := \frac{1}{1 + e^{-s}}\\
\frac{{t\_2}^{c\_p} \cdot {\left(1 - t\_2\right)}^{c\_n}}{{t\_1}^{c\_p} \cdot {\left(1 - t\_1\right)}^{c\_n}}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (c_p c_n t s)
:precision binary64
(let* ((t_1 (/ 1.0 (+ 1.0 (exp (- t))))) (t_2 (/ 1.0 (+ 1.0 (exp (- s))))))
(/
(* (pow t_2 c_p) (pow (- 1.0 t_2) c_n))
(* (pow t_1 c_p) (pow (- 1.0 t_1) c_n)))))
double code(double c_p, double c_n, double t, double s) {
double t_1 = 1.0 / (1.0 + exp(-t));
double t_2 = 1.0 / (1.0 + exp(-s));
return (pow(t_2, c_p) * pow((1.0 - t_2), c_n)) / (pow(t_1, c_p) * pow((1.0 - t_1), c_n));
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
real(8) :: t_1
real(8) :: t_2
t_1 = 1.0d0 / (1.0d0 + exp(-t))
t_2 = 1.0d0 / (1.0d0 + exp(-s))
code = ((t_2 ** c_p) * ((1.0d0 - t_2) ** c_n)) / ((t_1 ** c_p) * ((1.0d0 - t_1) ** c_n))
end function
public static double code(double c_p, double c_n, double t, double s) {
double t_1 = 1.0 / (1.0 + Math.exp(-t));
double t_2 = 1.0 / (1.0 + Math.exp(-s));
return (Math.pow(t_2, c_p) * Math.pow((1.0 - t_2), c_n)) / (Math.pow(t_1, c_p) * Math.pow((1.0 - t_1), c_n));
}
def code(c_p, c_n, t, s): t_1 = 1.0 / (1.0 + math.exp(-t)) t_2 = 1.0 / (1.0 + math.exp(-s)) return (math.pow(t_2, c_p) * math.pow((1.0 - t_2), c_n)) / (math.pow(t_1, c_p) * math.pow((1.0 - t_1), c_n))
function code(c_p, c_n, t, s) t_1 = Float64(1.0 / Float64(1.0 + exp(Float64(-t)))) t_2 = Float64(1.0 / Float64(1.0 + exp(Float64(-s)))) return Float64(Float64((t_2 ^ c_p) * (Float64(1.0 - t_2) ^ c_n)) / Float64((t_1 ^ c_p) * (Float64(1.0 - t_1) ^ c_n))) end
function tmp = code(c_p, c_n, t, s) t_1 = 1.0 / (1.0 + exp(-t)); t_2 = 1.0 / (1.0 + exp(-s)); tmp = ((t_2 ^ c_p) * ((1.0 - t_2) ^ c_n)) / ((t_1 ^ c_p) * ((1.0 - t_1) ^ c_n)); end
code[c$95$p_, c$95$n_, t_, s_] := Block[{t$95$1 = N[(1.0 / N[(1.0 + N[Exp[(-t)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / N[(1.0 + N[Exp[(-s)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Power[t$95$2, c$95$p], $MachinePrecision] * N[Power[N[(1.0 - t$95$2), $MachinePrecision], c$95$n], $MachinePrecision]), $MachinePrecision] / N[(N[Power[t$95$1, c$95$p], $MachinePrecision] * N[Power[N[(1.0 - t$95$1), $MachinePrecision], c$95$n], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \frac{1}{1 + e^{-t}}\\
t_2 := \frac{1}{1 + e^{-s}}\\
\frac{{t\_2}^{c\_p} \cdot {\left(1 - t\_2\right)}^{c\_n}}{{t\_1}^{c\_p} \cdot {\left(1 - t\_1\right)}^{c\_n}}
\end{array}
\end{array}
(FPCore (c_p c_n t s)
:precision binary64
(if (<= (- s) 100000000.0)
(exp
(+
(-
(*
c_n
(- (log1p (/ 1.0 (+ (exp s) 1.0))) (log1p (/ 1.0 (+ 1.0 (exp t))))))
(* c_p (log1p (exp s))))
(* c_p (log1p (exp t)))))
(/
(pow (/ 1.0 (+ 1.0 (exp (- s)))) c_p)
(- 1.0 (* c_p (log (+ 1.0 (exp (- t)))))))))
double code(double c_p, double c_n, double t, double s) {
double tmp;
if (-s <= 100000000.0) {
tmp = exp((((c_n * (log1p((1.0 / (exp(s) + 1.0))) - log1p((1.0 / (1.0 + exp(t)))))) - (c_p * log1p(exp(s)))) + (c_p * log1p(exp(t)))));
} else {
tmp = pow((1.0 / (1.0 + exp(-s))), c_p) / (1.0 - (c_p * log((1.0 + exp(-t)))));
}
return tmp;
}
public static double code(double c_p, double c_n, double t, double s) {
double tmp;
if (-s <= 100000000.0) {
tmp = Math.exp((((c_n * (Math.log1p((1.0 / (Math.exp(s) + 1.0))) - Math.log1p((1.0 / (1.0 + Math.exp(t)))))) - (c_p * Math.log1p(Math.exp(s)))) + (c_p * Math.log1p(Math.exp(t)))));
} else {
tmp = Math.pow((1.0 / (1.0 + Math.exp(-s))), c_p) / (1.0 - (c_p * Math.log((1.0 + Math.exp(-t)))));
}
return tmp;
}
def code(c_p, c_n, t, s): tmp = 0 if -s <= 100000000.0: tmp = math.exp((((c_n * (math.log1p((1.0 / (math.exp(s) + 1.0))) - math.log1p((1.0 / (1.0 + math.exp(t)))))) - (c_p * math.log1p(math.exp(s)))) + (c_p * math.log1p(math.exp(t))))) else: tmp = math.pow((1.0 / (1.0 + math.exp(-s))), c_p) / (1.0 - (c_p * math.log((1.0 + math.exp(-t))))) return tmp
function code(c_p, c_n, t, s) tmp = 0.0 if (Float64(-s) <= 100000000.0) tmp = exp(Float64(Float64(Float64(c_n * Float64(log1p(Float64(1.0 / Float64(exp(s) + 1.0))) - log1p(Float64(1.0 / Float64(1.0 + exp(t)))))) - Float64(c_p * log1p(exp(s)))) + Float64(c_p * log1p(exp(t))))); else tmp = Float64((Float64(1.0 / Float64(1.0 + exp(Float64(-s)))) ^ c_p) / Float64(1.0 - Float64(c_p * log(Float64(1.0 + exp(Float64(-t))))))); end return tmp end
code[c$95$p_, c$95$n_, t_, s_] := If[LessEqual[(-s), 100000000.0], N[Exp[N[(N[(N[(c$95$n * N[(N[Log[1 + N[(1.0 / N[(N[Exp[s], $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - N[Log[1 + N[(1.0 / N[(1.0 + N[Exp[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(c$95$p * N[Log[1 + N[Exp[s], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(c$95$p * N[Log[1 + N[Exp[t], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[(N[Power[N[(1.0 / N[(1.0 + N[Exp[(-s)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], c$95$p], $MachinePrecision] / N[(1.0 - N[(c$95$p * N[Log[N[(1.0 + N[Exp[(-t)], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;-s \leq 100000000:\\
\;\;\;\;e^{\left(c\_n \cdot \left(\mathsf{log1p}\left(\frac{1}{e^{s} + 1}\right) - \mathsf{log1p}\left(\frac{1}{1 + e^{t}}\right)\right) - c\_p \cdot \mathsf{log1p}\left(e^{s}\right)\right) + c\_p \cdot \mathsf{log1p}\left(e^{t}\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{{\left(\frac{1}{1 + e^{-s}}\right)}^{c\_p}}{1 - c\_p \cdot \log \left(1 + e^{-t}\right)}\\
\end{array}
\end{array}
if (neg.f64 s) < 1e8Initial program 93.3%
associate-/l/93.3%
Simplified93.3%
Applied egg-rr99.9%
*-lft-identity99.9%
associate--l+99.9%
distribute-lft-out--99.9%
Simplified99.9%
if 1e8 < (neg.f64 s) Initial program 80.0%
associate-/l/80.0%
Simplified80.0%
Taylor expanded in c_n around 0 80.0%
Taylor expanded in c_p around 0 100.0%
log-rec100.0%
Simplified100.0%
Final simplification99.9%
(FPCore (c_p c_n t s) :precision binary64 (exp (* c_n (* s (- (* s -0.013888888888888888) 0.16666666666666666)))))
double code(double c_p, double c_n, double t, double s) {
return exp((c_n * (s * ((s * -0.013888888888888888) - 0.16666666666666666))));
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
code = exp((c_n * (s * ((s * (-0.013888888888888888d0)) - 0.16666666666666666d0))))
end function
public static double code(double c_p, double c_n, double t, double s) {
return Math.exp((c_n * (s * ((s * -0.013888888888888888) - 0.16666666666666666))));
}
def code(c_p, c_n, t, s): return math.exp((c_n * (s * ((s * -0.013888888888888888) - 0.16666666666666666))))
function code(c_p, c_n, t, s) return exp(Float64(c_n * Float64(s * Float64(Float64(s * -0.013888888888888888) - 0.16666666666666666)))) end
function tmp = code(c_p, c_n, t, s) tmp = exp((c_n * (s * ((s * -0.013888888888888888) - 0.16666666666666666)))); end
code[c$95$p_, c$95$n_, t_, s_] := N[Exp[N[(c$95$n * N[(s * N[(N[(s * -0.013888888888888888), $MachinePrecision] - 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
e^{c\_n \cdot \left(s \cdot \left(s \cdot -0.013888888888888888 - 0.16666666666666666\right)\right)}
\end{array}
Initial program 93.0%
associate-/l/93.0%
Simplified93.0%
Applied egg-rr98.0%
*-lft-identity98.0%
associate--l+98.0%
distribute-lft-out--98.0%
Simplified98.0%
Taylor expanded in c_p around 0 97.7%
log1p-define97.7%
log1p-define97.7%
Simplified97.7%
Taylor expanded in t around 0 96.1%
log1p-define96.1%
Simplified96.1%
Taylor expanded in s around 0 98.0%
Final simplification98.0%
(FPCore (c_p c_n t s) :precision binary64 (exp (* s (* c_n -0.16666666666666666))))
double code(double c_p, double c_n, double t, double s) {
return exp((s * (c_n * -0.16666666666666666)));
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
code = exp((s * (c_n * (-0.16666666666666666d0))))
end function
public static double code(double c_p, double c_n, double t, double s) {
return Math.exp((s * (c_n * -0.16666666666666666)));
}
def code(c_p, c_n, t, s): return math.exp((s * (c_n * -0.16666666666666666)))
function code(c_p, c_n, t, s) return exp(Float64(s * Float64(c_n * -0.16666666666666666))) end
function tmp = code(c_p, c_n, t, s) tmp = exp((s * (c_n * -0.16666666666666666))); end
code[c$95$p_, c$95$n_, t_, s_] := N[Exp[N[(s * N[(c$95$n * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
e^{s \cdot \left(c\_n \cdot -0.16666666666666666\right)}
\end{array}
Initial program 93.0%
associate-/l/93.0%
Simplified93.0%
Applied egg-rr98.0%
*-lft-identity98.0%
associate--l+98.0%
distribute-lft-out--98.0%
Simplified98.0%
Taylor expanded in c_p around 0 97.7%
log1p-define97.7%
log1p-define97.7%
Simplified97.7%
Taylor expanded in t around 0 96.1%
log1p-define96.1%
Simplified96.1%
Taylor expanded in s around 0 96.9%
*-commutative96.9%
*-commutative96.9%
associate-*r*96.9%
Simplified96.9%
(FPCore (c_p c_n t s) :precision binary64 (+ 1.0 (* 0.5 (* s c_p))))
double code(double c_p, double c_n, double t, double s) {
return 1.0 + (0.5 * (s * c_p));
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
code = 1.0d0 + (0.5d0 * (s * c_p))
end function
public static double code(double c_p, double c_n, double t, double s) {
return 1.0 + (0.5 * (s * c_p));
}
def code(c_p, c_n, t, s): return 1.0 + (0.5 * (s * c_p))
function code(c_p, c_n, t, s) return Float64(1.0 + Float64(0.5 * Float64(s * c_p))) end
function tmp = code(c_p, c_n, t, s) tmp = 1.0 + (0.5 * (s * c_p)); end
code[c$95$p_, c$95$n_, t_, s_] := N[(1.0 + N[(0.5 * N[(s * c$95$p), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1 + 0.5 \cdot \left(s \cdot c\_p\right)
\end{array}
Initial program 93.0%
associate-/l/93.0%
Simplified93.0%
Taylor expanded in c_n around 0 93.9%
Taylor expanded in t around 0 94.3%
Taylor expanded in s around 0 93.9%
*-commutative93.9%
Simplified93.9%
(FPCore (c_p c_n t s) :precision binary64 1.0)
double code(double c_p, double c_n, double t, double s) {
return 1.0;
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
code = 1.0d0
end function
public static double code(double c_p, double c_n, double t, double s) {
return 1.0;
}
def code(c_p, c_n, t, s): return 1.0
function code(c_p, c_n, t, s) return 1.0 end
function tmp = code(c_p, c_n, t, s) tmp = 1.0; end
code[c$95$p_, c$95$n_, t_, s_] := 1.0
\begin{array}{l}
\\
1
\end{array}
Initial program 93.0%
associate-/l/93.0%
Simplified93.0%
Taylor expanded in c_n around 0 93.9%
Taylor expanded in c_p around 0 89.1%
Taylor expanded in c_p around 0 93.9%
(FPCore (c_p c_n t s) :precision binary64 (* (pow (/ (+ 1.0 (exp (- t))) (+ 1.0 (exp (- s)))) c_p) (pow (/ (+ 1.0 (exp t)) (+ 1.0 (exp s))) c_n)))
double code(double c_p, double c_n, double t, double s) {
return pow(((1.0 + exp(-t)) / (1.0 + exp(-s))), c_p) * pow(((1.0 + exp(t)) / (1.0 + exp(s))), c_n);
}
real(8) function code(c_p, c_n, t, s)
real(8), intent (in) :: c_p
real(8), intent (in) :: c_n
real(8), intent (in) :: t
real(8), intent (in) :: s
code = (((1.0d0 + exp(-t)) / (1.0d0 + exp(-s))) ** c_p) * (((1.0d0 + exp(t)) / (1.0d0 + exp(s))) ** c_n)
end function
public static double code(double c_p, double c_n, double t, double s) {
return Math.pow(((1.0 + Math.exp(-t)) / (1.0 + Math.exp(-s))), c_p) * Math.pow(((1.0 + Math.exp(t)) / (1.0 + Math.exp(s))), c_n);
}
def code(c_p, c_n, t, s): return math.pow(((1.0 + math.exp(-t)) / (1.0 + math.exp(-s))), c_p) * math.pow(((1.0 + math.exp(t)) / (1.0 + math.exp(s))), c_n)
function code(c_p, c_n, t, s) return Float64((Float64(Float64(1.0 + exp(Float64(-t))) / Float64(1.0 + exp(Float64(-s)))) ^ c_p) * (Float64(Float64(1.0 + exp(t)) / Float64(1.0 + exp(s))) ^ c_n)) end
function tmp = code(c_p, c_n, t, s) tmp = (((1.0 + exp(-t)) / (1.0 + exp(-s))) ^ c_p) * (((1.0 + exp(t)) / (1.0 + exp(s))) ^ c_n); end
code[c$95$p_, c$95$n_, t_, s_] := N[(N[Power[N[(N[(1.0 + N[Exp[(-t)], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Exp[(-s)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], c$95$p], $MachinePrecision] * N[Power[N[(N[(1.0 + N[Exp[t], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Exp[s], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], c$95$n], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{1 + e^{-t}}{1 + e^{-s}}\right)}^{c\_p} \cdot {\left(\frac{1 + e^{t}}{1 + e^{s}}\right)}^{c\_n}
\end{array}
herbie shell --seed 2024187
(FPCore (c_p c_n t s)
:name "Harley's example"
:precision binary64
:pre (and (< 0.0 c_p) (< 0.0 c_n))
:alt
(! :herbie-platform default (* (pow (/ (+ 1 (exp (- t))) (+ 1 (exp (- s)))) c_p) (pow (/ (+ 1 (exp t)) (+ 1 (exp s))) c_n)))
(/ (* (pow (/ 1.0 (+ 1.0 (exp (- s)))) c_p) (pow (- 1.0 (/ 1.0 (+ 1.0 (exp (- s))))) c_n)) (* (pow (/ 1.0 (+ 1.0 (exp (- t)))) c_p) (pow (- 1.0 (/ 1.0 (+ 1.0 (exp (- t))))) c_n))))