
(FPCore (t) :precision binary64 (let* ((t_1 (/ (* 2.0 t) (+ 1.0 t))) (t_2 (* t_1 t_1))) (/ (+ 1.0 t_2) (+ 2.0 t_2))))
double code(double t) {
double t_1 = (2.0 * t) / (1.0 + t);
double t_2 = t_1 * t_1;
return (1.0 + t_2) / (2.0 + t_2);
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: t_1
real(8) :: t_2
t_1 = (2.0d0 * t) / (1.0d0 + t)
t_2 = t_1 * t_1
code = (1.0d0 + t_2) / (2.0d0 + t_2)
end function
public static double code(double t) {
double t_1 = (2.0 * t) / (1.0 + t);
double t_2 = t_1 * t_1;
return (1.0 + t_2) / (2.0 + t_2);
}
def code(t): t_1 = (2.0 * t) / (1.0 + t) t_2 = t_1 * t_1 return (1.0 + t_2) / (2.0 + t_2)
function code(t) t_1 = Float64(Float64(2.0 * t) / Float64(1.0 + t)) t_2 = Float64(t_1 * t_1) return Float64(Float64(1.0 + t_2) / Float64(2.0 + t_2)) end
function tmp = code(t) t_1 = (2.0 * t) / (1.0 + t); t_2 = t_1 * t_1; tmp = (1.0 + t_2) / (2.0 + t_2); end
code[t_] := Block[{t$95$1 = N[(N[(2.0 * t), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * t$95$1), $MachinePrecision]}, N[(N[(1.0 + t$95$2), $MachinePrecision] / N[(2.0 + t$95$2), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \frac{2 \cdot t}{1 + t}\\
t_2 := t\_1 \cdot t\_1\\
\frac{1 + t\_2}{2 + t\_2}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (t) :precision binary64 (let* ((t_1 (/ (* 2.0 t) (+ 1.0 t))) (t_2 (* t_1 t_1))) (/ (+ 1.0 t_2) (+ 2.0 t_2))))
double code(double t) {
double t_1 = (2.0 * t) / (1.0 + t);
double t_2 = t_1 * t_1;
return (1.0 + t_2) / (2.0 + t_2);
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: t_1
real(8) :: t_2
t_1 = (2.0d0 * t) / (1.0d0 + t)
t_2 = t_1 * t_1
code = (1.0d0 + t_2) / (2.0d0 + t_2)
end function
public static double code(double t) {
double t_1 = (2.0 * t) / (1.0 + t);
double t_2 = t_1 * t_1;
return (1.0 + t_2) / (2.0 + t_2);
}
def code(t): t_1 = (2.0 * t) / (1.0 + t) t_2 = t_1 * t_1 return (1.0 + t_2) / (2.0 + t_2)
function code(t) t_1 = Float64(Float64(2.0 * t) / Float64(1.0 + t)) t_2 = Float64(t_1 * t_1) return Float64(Float64(1.0 + t_2) / Float64(2.0 + t_2)) end
function tmp = code(t) t_1 = (2.0 * t) / (1.0 + t); t_2 = t_1 * t_1; tmp = (1.0 + t_2) / (2.0 + t_2); end
code[t_] := Block[{t$95$1 = N[(N[(2.0 * t), $MachinePrecision] / N[(1.0 + t), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * t$95$1), $MachinePrecision]}, N[(N[(1.0 + t$95$2), $MachinePrecision] / N[(2.0 + t$95$2), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \frac{2 \cdot t}{1 + t}\\
t_2 := t\_1 \cdot t\_1\\
\frac{1 + t\_2}{2 + t\_2}
\end{array}
\end{array}
(FPCore (t) :precision binary64 (let* ((t_1 (/ t (- -1.0 t))) (t_2 (* 4.0 (* t_1 t_1)))) (/ (+ t_2 1.0) (+ t_2 2.0))))
double code(double t) {
double t_1 = t / (-1.0 - t);
double t_2 = 4.0 * (t_1 * t_1);
return (t_2 + 1.0) / (t_2 + 2.0);
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: t_1
real(8) :: t_2
t_1 = t / ((-1.0d0) - t)
t_2 = 4.0d0 * (t_1 * t_1)
code = (t_2 + 1.0d0) / (t_2 + 2.0d0)
end function
public static double code(double t) {
double t_1 = t / (-1.0 - t);
double t_2 = 4.0 * (t_1 * t_1);
return (t_2 + 1.0) / (t_2 + 2.0);
}
def code(t): t_1 = t / (-1.0 - t) t_2 = 4.0 * (t_1 * t_1) return (t_2 + 1.0) / (t_2 + 2.0)
function code(t) t_1 = Float64(t / Float64(-1.0 - t)) t_2 = Float64(4.0 * Float64(t_1 * t_1)) return Float64(Float64(t_2 + 1.0) / Float64(t_2 + 2.0)) end
function tmp = code(t) t_1 = t / (-1.0 - t); t_2 = 4.0 * (t_1 * t_1); tmp = (t_2 + 1.0) / (t_2 + 2.0); end
code[t_] := Block[{t$95$1 = N[(t / N[(-1.0 - t), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(4.0 * N[(t$95$1 * t$95$1), $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$2 + 1.0), $MachinePrecision] / N[(t$95$2 + 2.0), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \frac{t}{-1 - t}\\
t_2 := 4 \cdot \left(t\_1 \cdot t\_1\right)\\
\frac{t\_2 + 1}{t\_2 + 2}
\end{array}
\end{array}
Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (t)
:precision binary64
(if (or (<= t -0.33) (not (<= t 0.68)))
(+
0.8333333333333334
(/
(-
(/ (+ 0.037037037037037035 (/ 0.04938271604938271 t)) t)
0.2222222222222222)
t))
0.5))
double code(double t) {
double tmp;
if ((t <= -0.33) || !(t <= 0.68)) {
tmp = 0.8333333333333334 + ((((0.037037037037037035 + (0.04938271604938271 / t)) / t) - 0.2222222222222222) / t);
} else {
tmp = 0.5;
}
return tmp;
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: tmp
if ((t <= (-0.33d0)) .or. (.not. (t <= 0.68d0))) then
tmp = 0.8333333333333334d0 + ((((0.037037037037037035d0 + (0.04938271604938271d0 / t)) / t) - 0.2222222222222222d0) / t)
else
tmp = 0.5d0
end if
code = tmp
end function
public static double code(double t) {
double tmp;
if ((t <= -0.33) || !(t <= 0.68)) {
tmp = 0.8333333333333334 + ((((0.037037037037037035 + (0.04938271604938271 / t)) / t) - 0.2222222222222222) / t);
} else {
tmp = 0.5;
}
return tmp;
}
def code(t): tmp = 0 if (t <= -0.33) or not (t <= 0.68): tmp = 0.8333333333333334 + ((((0.037037037037037035 + (0.04938271604938271 / t)) / t) - 0.2222222222222222) / t) else: tmp = 0.5 return tmp
function code(t) tmp = 0.0 if ((t <= -0.33) || !(t <= 0.68)) tmp = Float64(0.8333333333333334 + Float64(Float64(Float64(Float64(0.037037037037037035 + Float64(0.04938271604938271 / t)) / t) - 0.2222222222222222) / t)); else tmp = 0.5; end return tmp end
function tmp_2 = code(t) tmp = 0.0; if ((t <= -0.33) || ~((t <= 0.68))) tmp = 0.8333333333333334 + ((((0.037037037037037035 + (0.04938271604938271 / t)) / t) - 0.2222222222222222) / t); else tmp = 0.5; end tmp_2 = tmp; end
code[t_] := If[Or[LessEqual[t, -0.33], N[Not[LessEqual[t, 0.68]], $MachinePrecision]], N[(0.8333333333333334 + N[(N[(N[(N[(0.037037037037037035 + N[(0.04938271604938271 / t), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision] - 0.2222222222222222), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], 0.5]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.33 \lor \neg \left(t \leq 0.68\right):\\
\;\;\;\;0.8333333333333334 + \frac{\frac{0.037037037037037035 + \frac{0.04938271604938271}{t}}{t} - 0.2222222222222222}{t}\\
\mathbf{else}:\\
\;\;\;\;0.5\\
\end{array}
\end{array}
if t < -0.330000000000000016 or 0.680000000000000049 < t Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around -inf 99.8%
mul-1-neg99.8%
unsub-neg99.8%
mul-1-neg99.8%
unsub-neg99.8%
associate-*r/99.8%
metadata-eval99.8%
Simplified99.8%
if -0.330000000000000016 < t < 0.680000000000000049Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around 0 99.6%
Final simplification99.7%
(FPCore (t)
:precision binary64
(if (or (<= t -0.52) (not (<= t 0.23)))
(+
0.8333333333333334
(/ (+ (/ 0.037037037037037035 t) -0.2222222222222222) t))
0.5))
double code(double t) {
double tmp;
if ((t <= -0.52) || !(t <= 0.23)) {
tmp = 0.8333333333333334 + (((0.037037037037037035 / t) + -0.2222222222222222) / t);
} else {
tmp = 0.5;
}
return tmp;
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: tmp
if ((t <= (-0.52d0)) .or. (.not. (t <= 0.23d0))) then
tmp = 0.8333333333333334d0 + (((0.037037037037037035d0 / t) + (-0.2222222222222222d0)) / t)
else
tmp = 0.5d0
end if
code = tmp
end function
public static double code(double t) {
double tmp;
if ((t <= -0.52) || !(t <= 0.23)) {
tmp = 0.8333333333333334 + (((0.037037037037037035 / t) + -0.2222222222222222) / t);
} else {
tmp = 0.5;
}
return tmp;
}
def code(t): tmp = 0 if (t <= -0.52) or not (t <= 0.23): tmp = 0.8333333333333334 + (((0.037037037037037035 / t) + -0.2222222222222222) / t) else: tmp = 0.5 return tmp
function code(t) tmp = 0.0 if ((t <= -0.52) || !(t <= 0.23)) tmp = Float64(0.8333333333333334 + Float64(Float64(Float64(0.037037037037037035 / t) + -0.2222222222222222) / t)); else tmp = 0.5; end return tmp end
function tmp_2 = code(t) tmp = 0.0; if ((t <= -0.52) || ~((t <= 0.23))) tmp = 0.8333333333333334 + (((0.037037037037037035 / t) + -0.2222222222222222) / t); else tmp = 0.5; end tmp_2 = tmp; end
code[t_] := If[Or[LessEqual[t, -0.52], N[Not[LessEqual[t, 0.23]], $MachinePrecision]], N[(0.8333333333333334 + N[(N[(N[(0.037037037037037035 / t), $MachinePrecision] + -0.2222222222222222), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], 0.5]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.52 \lor \neg \left(t \leq 0.23\right):\\
\;\;\;\;0.8333333333333334 + \frac{\frac{0.037037037037037035}{t} + -0.2222222222222222}{t}\\
\mathbf{else}:\\
\;\;\;\;0.5\\
\end{array}
\end{array}
if t < -0.52000000000000002 or 0.23000000000000001 < t Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around inf 99.6%
sub-neg99.6%
+-commutative99.6%
associate-+r+99.6%
+-commutative99.6%
sub-neg99.6%
associate--r-99.6%
associate-*r/99.6%
metadata-eval99.6%
unpow299.6%
associate-/r*99.6%
metadata-eval99.6%
associate-*r/99.6%
div-sub99.6%
unsub-neg99.6%
mul-1-neg99.6%
associate-*r/99.6%
Simplified99.6%
if -0.52000000000000002 < t < 0.23000000000000001Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around 0 99.6%
Final simplification99.6%
(FPCore (t) :precision binary64 (if (or (<= t -0.5) (not (<= t 0.66))) (- 0.8333333333333334 (/ 0.2222222222222222 t)) 0.5))
double code(double t) {
double tmp;
if ((t <= -0.5) || !(t <= 0.66)) {
tmp = 0.8333333333333334 - (0.2222222222222222 / t);
} else {
tmp = 0.5;
}
return tmp;
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: tmp
if ((t <= (-0.5d0)) .or. (.not. (t <= 0.66d0))) then
tmp = 0.8333333333333334d0 - (0.2222222222222222d0 / t)
else
tmp = 0.5d0
end if
code = tmp
end function
public static double code(double t) {
double tmp;
if ((t <= -0.5) || !(t <= 0.66)) {
tmp = 0.8333333333333334 - (0.2222222222222222 / t);
} else {
tmp = 0.5;
}
return tmp;
}
def code(t): tmp = 0 if (t <= -0.5) or not (t <= 0.66): tmp = 0.8333333333333334 - (0.2222222222222222 / t) else: tmp = 0.5 return tmp
function code(t) tmp = 0.0 if ((t <= -0.5) || !(t <= 0.66)) tmp = Float64(0.8333333333333334 - Float64(0.2222222222222222 / t)); else tmp = 0.5; end return tmp end
function tmp_2 = code(t) tmp = 0.0; if ((t <= -0.5) || ~((t <= 0.66))) tmp = 0.8333333333333334 - (0.2222222222222222 / t); else tmp = 0.5; end tmp_2 = tmp; end
code[t_] := If[Or[LessEqual[t, -0.5], N[Not[LessEqual[t, 0.66]], $MachinePrecision]], N[(0.8333333333333334 - N[(0.2222222222222222 / t), $MachinePrecision]), $MachinePrecision], 0.5]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.5 \lor \neg \left(t \leq 0.66\right):\\
\;\;\;\;0.8333333333333334 - \frac{0.2222222222222222}{t}\\
\mathbf{else}:\\
\;\;\;\;0.5\\
\end{array}
\end{array}
if t < -0.5 or 0.660000000000000031 < t Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around inf 98.8%
associate-*r/98.8%
metadata-eval98.8%
Simplified98.8%
if -0.5 < t < 0.660000000000000031Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around 0 99.6%
Final simplification99.2%
(FPCore (t) :precision binary64 (if (<= t -0.33) 0.8333333333333334 (if (<= t 1.0) 0.5 0.8333333333333334)))
double code(double t) {
double tmp;
if (t <= -0.33) {
tmp = 0.8333333333333334;
} else if (t <= 1.0) {
tmp = 0.5;
} else {
tmp = 0.8333333333333334;
}
return tmp;
}
real(8) function code(t)
real(8), intent (in) :: t
real(8) :: tmp
if (t <= (-0.33d0)) then
tmp = 0.8333333333333334d0
else if (t <= 1.0d0) then
tmp = 0.5d0
else
tmp = 0.8333333333333334d0
end if
code = tmp
end function
public static double code(double t) {
double tmp;
if (t <= -0.33) {
tmp = 0.8333333333333334;
} else if (t <= 1.0) {
tmp = 0.5;
} else {
tmp = 0.8333333333333334;
}
return tmp;
}
def code(t): tmp = 0 if t <= -0.33: tmp = 0.8333333333333334 elif t <= 1.0: tmp = 0.5 else: tmp = 0.8333333333333334 return tmp
function code(t) tmp = 0.0 if (t <= -0.33) tmp = 0.8333333333333334; elseif (t <= 1.0) tmp = 0.5; else tmp = 0.8333333333333334; end return tmp end
function tmp_2 = code(t) tmp = 0.0; if (t <= -0.33) tmp = 0.8333333333333334; elseif (t <= 1.0) tmp = 0.5; else tmp = 0.8333333333333334; end tmp_2 = tmp; end
code[t_] := If[LessEqual[t, -0.33], 0.8333333333333334, If[LessEqual[t, 1.0], 0.5, 0.8333333333333334]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;t \leq -0.33:\\
\;\;\;\;0.8333333333333334\\
\mathbf{elif}\;t \leq 1:\\
\;\;\;\;0.5\\
\mathbf{else}:\\
\;\;\;\;0.8333333333333334\\
\end{array}
\end{array}
if t < -0.330000000000000016 or 1 < t Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around inf 97.0%
if -0.330000000000000016 < t < 1Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around 0 99.6%
Final simplification98.3%
(FPCore (t) :precision binary64 0.5)
double code(double t) {
return 0.5;
}
real(8) function code(t)
real(8), intent (in) :: t
code = 0.5d0
end function
public static double code(double t) {
return 0.5;
}
def code(t): return 0.5
function code(t) return 0.5 end
function tmp = code(t) tmp = 0.5; end
code[t_] := 0.5
\begin{array}{l}
\\
0.5
\end{array}
Initial program 100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
associate-/l*100.0%
associate-/l*100.0%
swap-sqr100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in t around 0 57.4%
Final simplification57.4%
herbie shell --seed 2024080
(FPCore (t)
:name "Kahan p13 Example 1"
:precision binary64
(/ (+ 1.0 (* (/ (* 2.0 t) (+ 1.0 t)) (/ (* 2.0 t) (+ 1.0 t)))) (+ 2.0 (* (/ (* 2.0 t) (+ 1.0 t)) (/ (* 2.0 t) (+ 1.0 t))))))