
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
return log((N + 1.0)) - log(N);
}
real(8) function code(n)
real(8), intent (in) :: n
code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
return Math.log((N + 1.0)) - Math.log(N);
}
def code(N): return math.log((N + 1.0)) - math.log(N)
function code(N) return Float64(log(Float64(N + 1.0)) - log(N)) end
function tmp = code(N) tmp = log((N + 1.0)) - log(N); end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\log \left(N + 1\right) - \log N
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (N) :precision binary64 (- (log (+ N 1.0)) (log N)))
double code(double N) {
return log((N + 1.0)) - log(N);
}
real(8) function code(n)
real(8), intent (in) :: n
code = log((n + 1.0d0)) - log(n)
end function
public static double code(double N) {
return Math.log((N + 1.0)) - Math.log(N);
}
def code(N): return math.log((N + 1.0)) - math.log(N)
function code(N) return Float64(log(Float64(N + 1.0)) - log(N)) end
function tmp = code(N) tmp = log((N + 1.0)) - log(N); end
code[N_] := N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\log \left(N + 1\right) - \log N
\end{array}
(FPCore (N) :precision binary64 (if (<= (- (log (+ N 1.0)) (log N)) 0.001) (/ (- (/ (- -0.5 (/ (fma -0.3333333333333333 N 0.25) (* N N))) N) -1.0) N) (- (log (/ N (+ 1.0 N))))))
double code(double N) {
double tmp;
if ((log((N + 1.0)) - log(N)) <= 0.001) {
tmp = (((-0.5 - (fma(-0.3333333333333333, N, 0.25) / (N * N))) / N) - -1.0) / N;
} else {
tmp = -log((N / (1.0 + N)));
}
return tmp;
}
function code(N) tmp = 0.0 if (Float64(log(Float64(N + 1.0)) - log(N)) <= 0.001) tmp = Float64(Float64(Float64(Float64(-0.5 - Float64(fma(-0.3333333333333333, N, 0.25) / Float64(N * N))) / N) - -1.0) / N); else tmp = Float64(-log(Float64(N / Float64(1.0 + N)))); end return tmp end
code[N_] := If[LessEqual[N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision], 0.001], N[(N[(N[(N[(-0.5 - N[(N[(-0.3333333333333333 * N + 0.25), $MachinePrecision] / N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - -1.0), $MachinePrecision] / N), $MachinePrecision], (-N[Log[N[(N / N[(1.0 + N), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.001:\\
\;\;\;\;\frac{\frac{-0.5 - \frac{\mathsf{fma}\left(-0.3333333333333333, N, 0.25\right)}{N \cdot N}}{N} - -1}{N}\\
\mathbf{else}:\\
\;\;\;\;-\log \left(\frac{N}{1 + N}\right)\\
\end{array}
\end{array}
if (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) < 1e-3Initial program 18.2%
Taylor expanded in N around inf
Applied rewrites99.7%
Taylor expanded in N around 0
Applied rewrites99.7%
if 1e-3 < (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) Initial program 91.6%
lift--.f64N/A
lift-log.f64N/A
lift-log.f64N/A
diff-logN/A
clear-numN/A
clear-numN/A
log-recN/A
lower-neg.f64N/A
lower-log.f64N/A
lower-/.f64N/A
lower-/.f6495.0
lift-+.f64N/A
+-commutativeN/A
lower-+.f6495.0
Applied rewrites95.0%
Final simplification99.5%
(FPCore (N) :precision binary64 (if (<= (- (log (+ N 1.0)) (log N)) 0.001) (/ (- (/ (- -0.5 (/ (fma -0.3333333333333333 N 0.25) (* N N))) N) -1.0) N) (log (+ (pow N -1.0) 1.0))))
double code(double N) {
double tmp;
if ((log((N + 1.0)) - log(N)) <= 0.001) {
tmp = (((-0.5 - (fma(-0.3333333333333333, N, 0.25) / (N * N))) / N) - -1.0) / N;
} else {
tmp = log((pow(N, -1.0) + 1.0));
}
return tmp;
}
function code(N) tmp = 0.0 if (Float64(log(Float64(N + 1.0)) - log(N)) <= 0.001) tmp = Float64(Float64(Float64(Float64(-0.5 - Float64(fma(-0.3333333333333333, N, 0.25) / Float64(N * N))) / N) - -1.0) / N); else tmp = log(Float64((N ^ -1.0) + 1.0)); end return tmp end
code[N_] := If[LessEqual[N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision], 0.001], N[(N[(N[(N[(-0.5 - N[(N[(-0.3333333333333333 * N + 0.25), $MachinePrecision] / N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - -1.0), $MachinePrecision] / N), $MachinePrecision], N[Log[N[(N[Power[N, -1.0], $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.001:\\
\;\;\;\;\frac{\frac{-0.5 - \frac{\mathsf{fma}\left(-0.3333333333333333, N, 0.25\right)}{N \cdot N}}{N} - -1}{N}\\
\mathbf{else}:\\
\;\;\;\;\log \left({N}^{-1} + 1\right)\\
\end{array}
\end{array}
if (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) < 1e-3Initial program 18.2%
Taylor expanded in N around inf
Applied rewrites99.7%
Taylor expanded in N around 0
Applied rewrites99.7%
if 1e-3 < (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) Initial program 91.6%
lift--.f64N/A
lift-log.f64N/A
lift-log.f64N/A
diff-logN/A
lower-log.f64N/A
lower-/.f6493.3
lift-+.f64N/A
+-commutativeN/A
lower-+.f6493.3
Applied rewrites93.3%
Taylor expanded in N around inf
+-commutativeN/A
lower-+.f64N/A
lower-/.f6493.3
Applied rewrites93.3%
Final simplification99.4%
(FPCore (N) :precision binary64 (if (<= (- (log (+ N 1.0)) (log N)) 0.001) (/ (- (/ (- -0.5 (/ (fma -0.3333333333333333 N 0.25) (* N N))) N) -1.0) N) (- (log (/ (* (- N 1.0) N) (fma N N -1.0))))))
double code(double N) {
double tmp;
if ((log((N + 1.0)) - log(N)) <= 0.001) {
tmp = (((-0.5 - (fma(-0.3333333333333333, N, 0.25) / (N * N))) / N) - -1.0) / N;
} else {
tmp = -log((((N - 1.0) * N) / fma(N, N, -1.0)));
}
return tmp;
}
function code(N) tmp = 0.0 if (Float64(log(Float64(N + 1.0)) - log(N)) <= 0.001) tmp = Float64(Float64(Float64(Float64(-0.5 - Float64(fma(-0.3333333333333333, N, 0.25) / Float64(N * N))) / N) - -1.0) / N); else tmp = Float64(-log(Float64(Float64(Float64(N - 1.0) * N) / fma(N, N, -1.0)))); end return tmp end
code[N_] := If[LessEqual[N[(N[Log[N[(N + 1.0), $MachinePrecision]], $MachinePrecision] - N[Log[N], $MachinePrecision]), $MachinePrecision], 0.001], N[(N[(N[(N[(-0.5 - N[(N[(-0.3333333333333333 * N + 0.25), $MachinePrecision] / N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - -1.0), $MachinePrecision] / N), $MachinePrecision], (-N[Log[N[(N[(N[(N - 1.0), $MachinePrecision] * N), $MachinePrecision] / N[(N * N + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\log \left(N + 1\right) - \log N \leq 0.001:\\
\;\;\;\;\frac{\frac{-0.5 - \frac{\mathsf{fma}\left(-0.3333333333333333, N, 0.25\right)}{N \cdot N}}{N} - -1}{N}\\
\mathbf{else}:\\
\;\;\;\;-\log \left(\frac{\left(N - 1\right) \cdot N}{\mathsf{fma}\left(N, N, -1\right)}\right)\\
\end{array}
\end{array}
if (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) < 1e-3Initial program 18.2%
Taylor expanded in N around inf
Applied rewrites99.7%
Taylor expanded in N around 0
Applied rewrites99.7%
if 1e-3 < (-.f64 (log.f64 (+.f64 N #s(literal 1 binary64))) (log.f64 N)) Initial program 91.6%
lift--.f64N/A
lift-log.f64N/A
lift-log.f64N/A
diff-logN/A
lift-+.f64N/A
flip-+N/A
associate-/l/N/A
clear-numN/A
log-recN/A
lower-neg.f64N/A
lower-log.f64N/A
distribute-rgt-out--N/A
lower-/.f64N/A
distribute-rgt-out--N/A
*-commutativeN/A
lower-*.f64N/A
lower--.f64N/A
metadata-evalN/A
sub-negN/A
lower-fma.f64N/A
metadata-eval94.5
Applied rewrites94.5%
(FPCore (N)
:precision binary64
(pow
(*
(fma
(/ (- 0.5 (/ (- 0.08333333333333333 (/ 0.041666666666666664 N)) N)) N)
-1.0
-1.0)
(- N))
-1.0))
double code(double N) {
return pow((fma(((0.5 - ((0.08333333333333333 - (0.041666666666666664 / N)) / N)) / N), -1.0, -1.0) * -N), -1.0);
}
function code(N) return Float64(fma(Float64(Float64(0.5 - Float64(Float64(0.08333333333333333 - Float64(0.041666666666666664 / N)) / N)) / N), -1.0, -1.0) * Float64(-N)) ^ -1.0 end
code[N_] := N[Power[N[(N[(N[(N[(0.5 - N[(N[(0.08333333333333333 - N[(0.041666666666666664 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] * -1.0 + -1.0), $MachinePrecision] * (-N)), $MachinePrecision], -1.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\mathsf{fma}\left(\frac{0.5 - \frac{0.08333333333333333 - \frac{0.041666666666666664}{N}}{N}}{N}, -1, -1\right) \cdot \left(-N\right)\right)}^{-1}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in N around -inf
Applied rewrites97.7%
Final simplification97.7%
(FPCore (N) :precision binary64 (pow (* (+ (/ (- 0.5 (/ 0.08333333333333333 N)) N) 1.0) N) -1.0))
double code(double N) {
return pow(((((0.5 - (0.08333333333333333 / N)) / N) + 1.0) * N), -1.0);
}
real(8) function code(n)
real(8), intent (in) :: n
code = ((((0.5d0 - (0.08333333333333333d0 / n)) / n) + 1.0d0) * n) ** (-1.0d0)
end function
public static double code(double N) {
return Math.pow(((((0.5 - (0.08333333333333333 / N)) / N) + 1.0) * N), -1.0);
}
def code(N): return math.pow(((((0.5 - (0.08333333333333333 / N)) / N) + 1.0) * N), -1.0)
function code(N) return Float64(Float64(Float64(Float64(0.5 - Float64(0.08333333333333333 / N)) / N) + 1.0) * N) ^ -1.0 end
function tmp = code(N) tmp = ((((0.5 - (0.08333333333333333 / N)) / N) + 1.0) * N) ^ -1.0; end
code[N_] := N[Power[N[(N[(N[(N[(0.5 - N[(0.08333333333333333 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] + 1.0), $MachinePrecision] * N), $MachinePrecision], -1.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\left(\frac{0.5 - \frac{0.08333333333333333}{N}}{N} + 1\right) \cdot N\right)}^{-1}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in N around inf
Applied rewrites96.5%
Final simplification96.5%
(FPCore (N) :precision binary64 (pow (fma (/ 0.5 N) N N) -1.0))
double code(double N) {
return pow(fma((0.5 / N), N, N), -1.0);
}
function code(N) return fma(Float64(0.5 / N), N, N) ^ -1.0 end
code[N_] := N[Power[N[(N[(0.5 / N), $MachinePrecision] * N + N), $MachinePrecision], -1.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\mathsf{fma}\left(\frac{0.5}{N}, N, N\right)\right)}^{-1}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in N around inf
Applied rewrites94.0%
Final simplification94.0%
(FPCore (N) :precision binary64 (pow N -1.0))
double code(double N) {
return pow(N, -1.0);
}
real(8) function code(n)
real(8), intent (in) :: n
code = n ** (-1.0d0)
end function
public static double code(double N) {
return Math.pow(N, -1.0);
}
def code(N): return math.pow(N, -1.0)
function code(N) return N ^ -1.0 end
function tmp = code(N) tmp = N ^ -1.0; end
code[N_] := N[Power[N, -1.0], $MachinePrecision]
\begin{array}{l}
\\
{N}^{-1}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
lower-/.f6486.0
Applied rewrites86.0%
Final simplification86.0%
(FPCore (N) :precision binary64 (/ (- (/ (- -0.5 (/ (fma -0.3333333333333333 N 0.25) (* N N))) N) -1.0) N))
double code(double N) {
return (((-0.5 - (fma(-0.3333333333333333, N, 0.25) / (N * N))) / N) - -1.0) / N;
}
function code(N) return Float64(Float64(Float64(Float64(-0.5 - Float64(fma(-0.3333333333333333, N, 0.25) / Float64(N * N))) / N) - -1.0) / N) end
code[N_] := N[(N[(N[(N[(-0.5 - N[(N[(-0.3333333333333333 * N + 0.25), $MachinePrecision] / N[(N * N), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision] - -1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-0.5 - \frac{\mathsf{fma}\left(-0.3333333333333333, N, 0.25\right)}{N \cdot N}}{N} - -1}{N}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
Applied rewrites97.5%
Taylor expanded in N around 0
Applied rewrites97.5%
(FPCore (N) :precision binary64 (/ (- (/ (- (/ 0.3333333333333333 N) 0.5) N) -1.0) N))
double code(double N) {
return ((((0.3333333333333333 / N) - 0.5) / N) - -1.0) / N;
}
real(8) function code(n)
real(8), intent (in) :: n
code = ((((0.3333333333333333d0 / n) - 0.5d0) / n) - (-1.0d0)) / n
end function
public static double code(double N) {
return ((((0.3333333333333333 / N) - 0.5) / N) - -1.0) / N;
}
def code(N): return ((((0.3333333333333333 / N) - 0.5) / N) - -1.0) / N
function code(N) return Float64(Float64(Float64(Float64(Float64(0.3333333333333333 / N) - 0.5) / N) - -1.0) / N) end
function tmp = code(N) tmp = ((((0.3333333333333333 / N) - 0.5) / N) - -1.0) / N; end
code[N_] := N[(N[(N[(N[(N[(0.3333333333333333 / N), $MachinePrecision] - 0.5), $MachinePrecision] / N), $MachinePrecision] - -1.0), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{\frac{0.3333333333333333}{N} - 0.5}{N} - -1}{N}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
lower-/.f64N/A
Applied rewrites96.2%
(FPCore (N) :precision binary64 (/ (- 1.0 (/ 0.5 N)) N))
double code(double N) {
return (1.0 - (0.5 / N)) / N;
}
real(8) function code(n)
real(8), intent (in) :: n
code = (1.0d0 - (0.5d0 / n)) / n
end function
public static double code(double N) {
return (1.0 - (0.5 / N)) / N;
}
def code(N): return (1.0 - (0.5 / N)) / N
function code(N) return Float64(Float64(1.0 - Float64(0.5 / N)) / N) end
function tmp = code(N) tmp = (1.0 - (0.5 / N)) / N; end
code[N_] := N[(N[(1.0 - N[(0.5 / N), $MachinePrecision]), $MachinePrecision] / N), $MachinePrecision]
\begin{array}{l}
\\
\frac{1 - \frac{0.5}{N}}{N}
\end{array}
Initial program 21.9%
Taylor expanded in N around inf
lower-/.f64N/A
lower--.f64N/A
associate-*r/N/A
metadata-evalN/A
lower-/.f6493.4
Applied rewrites93.4%
(FPCore (N) :precision binary64 0.0)
double code(double N) {
return 0.0;
}
real(8) function code(n)
real(8), intent (in) :: n
code = 0.0d0
end function
public static double code(double N) {
return 0.0;
}
def code(N): return 0.0
function code(N) return 0.0 end
function tmp = code(N) tmp = 0.0; end
code[N_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 21.9%
lift--.f64N/A
flip--N/A
lower-/.f64N/A
lower--.f64N/A
pow2N/A
lower-pow.f64N/A
lift-log.f64N/A
lift-+.f64N/A
+-commutativeN/A
lower-log1p.f64N/A
pow2N/A
lower-pow.f64N/A
+-commutativeN/A
lower-+.f6421.8
lift-log.f64N/A
lift-+.f64N/A
+-commutativeN/A
lower-log1p.f6421.8
Applied rewrites21.8%
lift--.f64N/A
sub-negN/A
lift-neg.f64N/A
+-commutativeN/A
lift-neg.f64N/A
lift-pow.f64N/A
unpow2N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
lower-neg.f6423.9
Applied rewrites23.9%
Taylor expanded in N around -inf
distribute-lft1-inN/A
metadata-evalN/A
associate-*r/N/A
mul0-lft3.3
Applied rewrites3.3%
Final simplification3.3%
(FPCore (N) :precision binary64 (+ (+ (+ (/ 1.0 N) (/ -1.0 (* 2.0 (pow N 2.0)))) (/ 1.0 (* 3.0 (pow N 3.0)))) (/ -1.0 (* 4.0 (pow N 4.0)))))
double code(double N) {
return (((1.0 / N) + (-1.0 / (2.0 * pow(N, 2.0)))) + (1.0 / (3.0 * pow(N, 3.0)))) + (-1.0 / (4.0 * pow(N, 4.0)));
}
real(8) function code(n)
real(8), intent (in) :: n
code = (((1.0d0 / n) + ((-1.0d0) / (2.0d0 * (n ** 2.0d0)))) + (1.0d0 / (3.0d0 * (n ** 3.0d0)))) + ((-1.0d0) / (4.0d0 * (n ** 4.0d0)))
end function
public static double code(double N) {
return (((1.0 / N) + (-1.0 / (2.0 * Math.pow(N, 2.0)))) + (1.0 / (3.0 * Math.pow(N, 3.0)))) + (-1.0 / (4.0 * Math.pow(N, 4.0)));
}
def code(N): return (((1.0 / N) + (-1.0 / (2.0 * math.pow(N, 2.0)))) + (1.0 / (3.0 * math.pow(N, 3.0)))) + (-1.0 / (4.0 * math.pow(N, 4.0)))
function code(N) return Float64(Float64(Float64(Float64(1.0 / N) + Float64(-1.0 / Float64(2.0 * (N ^ 2.0)))) + Float64(1.0 / Float64(3.0 * (N ^ 3.0)))) + Float64(-1.0 / Float64(4.0 * (N ^ 4.0)))) end
function tmp = code(N) tmp = (((1.0 / N) + (-1.0 / (2.0 * (N ^ 2.0)))) + (1.0 / (3.0 * (N ^ 3.0)))) + (-1.0 / (4.0 * (N ^ 4.0))); end
code[N_] := N[(N[(N[(N[(1.0 / N), $MachinePrecision] + N[(-1.0 / N[(2.0 * N[Power[N, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(3.0 * N[Power[N, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / N[(4.0 * N[Power[N, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(\frac{1}{N} + \frac{-1}{2 \cdot {N}^{2}}\right) + \frac{1}{3 \cdot {N}^{3}}\right) + \frac{-1}{4 \cdot {N}^{4}}
\end{array}
herbie shell --seed 2024324
(FPCore (N)
:name "2log (problem 3.3.6)"
:precision binary64
:pre (and (> N 1.0) (< N 1e+40))
:alt
(! :herbie-platform default (+ (/ 1 N) (/ -1 (* 2 (pow N 2))) (/ 1 (* 3 (pow N 3))) (/ -1 (* 4 (pow N 4)))))
(- (log (+ N 1.0)) (log N)))