Average Error: 0.0 → 0.0
Time: 28.1s
Precision: 64
Internal Precision: 128
\[\frac{2}{e^{x} + e^{-x}}\]
\[\frac{\sqrt[3]{\frac{8}{e^{x} + e^{-x}}}}{\sqrt[3]{\left(e^{x} + e^{-x}\right) \cdot \left(e^{x} + e^{-x}\right)}}\]

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 0.0

    \[\frac{2}{e^{x} + e^{-x}}\]
  2. Using strategy rm
  3. Applied add-cbrt-cube0.1

    \[\leadsto \color{blue}{\sqrt[3]{\left(\frac{2}{e^{x} + e^{-x}} \cdot \frac{2}{e^{x} + e^{-x}}\right) \cdot \frac{2}{e^{x} + e^{-x}}}}\]
  4. Using strategy rm
  5. Applied associate-*l/0.1

    \[\leadsto \sqrt[3]{\color{blue}{\frac{2 \cdot \frac{2}{e^{x} + e^{-x}}}{e^{x} + e^{-x}}} \cdot \frac{2}{e^{x} + e^{-x}}}\]
  6. Applied frac-times0.1

    \[\leadsto \sqrt[3]{\color{blue}{\frac{\left(2 \cdot \frac{2}{e^{x} + e^{-x}}\right) \cdot 2}{\left(e^{x} + e^{-x}\right) \cdot \left(e^{x} + e^{-x}\right)}}}\]
  7. Applied cbrt-div0.0

    \[\leadsto \color{blue}{\frac{\sqrt[3]{\left(2 \cdot \frac{2}{e^{x} + e^{-x}}\right) \cdot 2}}{\sqrt[3]{\left(e^{x} + e^{-x}\right) \cdot \left(e^{x} + e^{-x}\right)}}}\]
  8. Simplified0.0

    \[\leadsto \frac{\color{blue}{\sqrt[3]{\frac{8}{e^{x} + e^{-x}}}}}{\sqrt[3]{\left(e^{x} + e^{-x}\right) \cdot \left(e^{x} + e^{-x}\right)}}\]
  9. Final simplification0.0

    \[\leadsto \frac{\sqrt[3]{\frac{8}{e^{x} + e^{-x}}}}{\sqrt[3]{\left(e^{x} + e^{-x}\right) \cdot \left(e^{x} + e^{-x}\right)}}\]

Reproduce

herbie shell --seed 2019007 
(FPCore (x)
  :name "Hyperbolic secant"
  (/ 2 (+ (exp x) (exp (- x)))))

Details

Time bar (total: 27.7s)Debug log

sample35.0ms

Algorithm
intervals

simplify9.0ms

Counts
1 → 1
Calls

1 calls. Slowest were:

8.0ms
(/ 2 (+ (exp x) (exp (- x))))

prune17.0ms

Pruning

1 alts after pruning (1 fresh and 0 done)

Merged error: 0.0b

localize27.0ms

Local error

Found 2 expressions with local error:

0.0b
(+ (exp x) (exp (- x)))
0.0b
(/ 2 (+ (exp x) (exp (- x))))

rewrite13.0ms

Algorithm
rewrite-expression-head
Counts
2 → 28
Calls

2 calls. Slowest were:

7.0ms
(+ (exp x) (exp (- x)))
5.0ms
(/ 2 (+ (exp x) (exp (- x))))

series70.0ms

Counts
2 → 6
Calls

2 calls. Slowest were:

41.0ms
(/ 2 (+ (exp x) (exp (- x))))
28.0ms
(+ (exp x) (exp (- x)))

simplify328.0ms

Counts
14 → 34
Calls

14 calls. Slowest were:

153.0ms
(+ (* (exp x) (exp x)) (- (* (exp (- x)) (exp (- x))) (* (exp x) (exp (- x)))))
68.0ms
(- (+ (* 5/24 (pow x 4)) 1) (* 1/2 (pow x 2)))
19.0ms
(+ (pow x 2) (+ (* 1/12 (pow x 4)) 2))

prune343.0ms

Pruning

2 alts after pruning (2 fresh and 0 done)

Merged error: 0b

localize9.0ms

Local error

Found 4 expressions with local error:

0.0b
(cbrt (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))))
0.0b
(* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x)))))
0.0b
(* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x)))))
0.0b
(+ (exp x) (exp (- x)))

rewrite26.0ms

Algorithm
rewrite-expression-head
Counts
4 → 93
Calls

4 calls. Slowest were:

10.0ms
(* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x)))))
7.0ms
(cbrt (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))))
4.0ms
(* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x)))))

series212.0ms

Counts
4 → 12
Calls

4 calls. Slowest were:

80.0ms
(* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x)))))
49.0ms
(cbrt (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))))
44.0ms
(* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x)))))
38.0ms
(+ (exp x) (exp (- x)))

simplify5.0s

Counts
75 → 105
Calls

75 calls. Slowest were:

784.0ms
(* (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))) (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))))
360.0ms
(/ 8 (pow (+ (exp (* -1 x)) (exp x)) 3))
309.0ms
(* (* (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))) (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x)))))) (* (* (/ 2 (+ (exp x) (exp (- x)))) (/ 2 (+ (exp x) (exp (- x))))) (/ 2 (+ (exp x) (exp (- x))))))

prune1.1s

Pruning

2 alts after pruning (1 fresh and 1 done)

Merged error: 0b

localize14.0ms

Local error

Found 4 expressions with local error:

0.0b
(cbrt (/ 8 (+ (exp x) (exp (- x)))))
0.0b
(* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))
0.0b
(/ (cbrt (/ 8 (+ (exp x) (exp (- x))))) (cbrt (* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))))
0.0b
(+ (exp x) (exp (- x)))

rewrite26.0ms

Algorithm
rewrite-expression-head
Counts
4 → 129
Calls

4 calls. Slowest were:

14.0ms
(* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))
6.0ms
(/ (cbrt (/ 8 (+ (exp x) (exp (- x))))) (cbrt (* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))))
4.0ms
(+ (exp x) (exp (- x)))

series346.0ms

Counts
4 → 12
Calls

4 calls. Slowest were:

216.0ms
(cbrt (/ 8 (+ (exp x) (exp (- x)))))
48.0ms
(* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))
41.0ms
(/ (cbrt (/ 8 (+ (exp x) (exp (- x))))) (cbrt (* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))))
41.0ms
(+ (exp x) (exp (- x)))

simplify17.6s

Counts
142 → 141
Calls

142 calls. Slowest were:

550.0ms
(cbrt (cbrt (* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x))))))
428.0ms
(/ (cbrt (/ 8 (+ (pow (exp x) 3) (pow (exp (- x)) 3)))) (sqrt (cbrt (* (+ (exp x) (exp (- x))) (+ (exp x) (exp (- x)))))))
399.0ms
(* (+ (pow (exp x) 3) (pow (exp (- x)) 3)) (+ (pow (exp x) 3) (pow (exp (- x)) 3)))

prune1.7s

Pruning

2 alts after pruning (0 fresh and 2 done)

Merged error: 0b

regimes65.0ms

Accuracy

0% (0.0b remaining)

Error of 0.0b against oracle of 0.0b and baseline of 0.0b

bsearch1.0ms

end0.0ms

sample761.0ms

Algorithm
intervals