Average Error: 0.3 → 0.3
Time: 5.8s
Precision: 64
Internal Precision: 128
\[\frac{a}{-\cos^{-1} a}\]
\[\frac{a}{-\cos^{-1} a}\]

Error

Bits error versus a

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 0.3

    \[\frac{a}{-\cos^{-1} a}\]
  2. Final simplification0.3

    \[\leadsto \frac{a}{-\cos^{-1} a}\]

Reproduce

herbie shell --seed 2019010 
(FPCore (a)
  :name "Fuzzer 001"
  (/ a (- (acos a))))

Details

Time bar (total: 5.3s)Debug log

sample33.0ms

Algorithm
intervals

simplify1.0ms

Counts
1 → 1
Calls
1 calls:
Slowest
1.0ms
(/ a (- (acos a)))

prune4.0ms

Pruning

1 alts after pruning (1 fresh and 0 done)

Merged error: 0.3b

localize8.0ms

Local error

Found 1 expressions with local error:

0.3b
(/ a (- (acos a)))

rewrite1.0ms

Algorithm
rewrite-expression-head
Rules
10×associate-/r*
add-cube-cbrt
*-un-lft-identity
add-sqr-sqrt
distribute-rgt-neg-in
distribute-lft-neg-in
add-log-exp
div-inv
add-exp-log
add-cbrt-cube
frac-2neg
neg-mul-1
clear-num
pow1
Counts
1 → 20
Calls
1 calls:
Slowest
1.0ms
(/ a (- (acos a)))

series24.0ms

Counts
1 → 3
Calls
1 calls:
Slowest
24.0ms
(/ a (- (acos a)))

simplify29.0ms

Counts
13 → 23
Calls
13 calls:
Slowest
7.0ms
(* -1 (/ a (acos a)))
7.0ms
(* -1 (/ a (acos a)))
7.0ms
(* -1 (/ a (acos a)))
1.0ms
(sqrt (- (acos a)))
1.0ms
(cbrt (- (acos a)))

prune120.0ms

Pruning

5 alts after pruning (4 fresh and 1 done)

Merged error: 0.1b

localize6.0ms

Local error

Found 2 expressions with local error:

0.3b
(/ 1 (/ (- (acos a)) a))
0.2b
(/ (- (acos a)) a)

rewrite5.0ms

Algorithm
rewrite-expression-head
Rules
10×associate-/l*
add-cube-cbrt
*-un-lft-identity
add-sqr-sqrt
associate-/r*
div-inv
add-exp-log
distribute-rgt-neg-in
pow1
distribute-lft-neg-in
add-log-exp
add-cbrt-cube
frac-2neg
clear-num
inv-pow
pow-flip
associate-/r/
distribute-frac-neg
div-sub
neg-mul-1
rec-exp
neg-sub0
Counts
2 → 40
Calls
2 calls:
Slowest
3.0ms
(/ (- (acos a)) a)
1.0ms
(/ 1 (/ (- (acos a)) a))

series34.0ms

Counts
2 → 6
Calls
2 calls:
Slowest
20.0ms
(/ (- (acos a)) a)
15.0ms
(/ 1 (/ (- (acos a)) a))

simplify132.0ms

Counts
20 → 46
Calls
20 calls:
Slowest
16.0ms
(* -1 (/ (acos a) a))
16.0ms
(* -1 (/ (acos a) a))
16.0ms
(* -1 (/ a (acos a)))
16.0ms
(* -1 (/ a (acos a)))
15.0ms
(* -1 (/ (acos a) a))

prune347.0ms

Pruning

10 alts after pruning (8 fresh and 2 done)

Merged error: 0.1b

localize15.0ms

Local error

Found 2 expressions with local error:

0.3b
(* (- (acos a)) (/ 1 a))
0.3b
(/ 1 (* (- (acos a)) (/ 1 a)))

rewrite15.0ms

Algorithm
rewrite-expression-head
Rules
10×associate-*l*
add-exp-log
pow1
add-cube-cbrt
*-un-lft-identity
add-sqr-sqrt
associate-*r*
add-cbrt-cube
distribute-rgt-neg-in
distribute-lft-neg-in
add-log-exp
pow-flip
div-inv
un-div-inv
associate-/r/
associate-*r/
prod-exp
pow-prod-down
rec-exp
inv-pow
cbrt-unprod
*-commutative
frac-2neg
neg-mul-1
associate-/r*
clear-num
distribute-lft-neg-out
Counts
2 → 46
Calls
2 calls:
Slowest
8.0ms
(* (- (acos a)) (/ 1 a))
6.0ms
(/ 1 (* (- (acos a)) (/ 1 a)))

series52.0ms

Counts
2 → 6
Calls
2 calls:
Slowest
27.0ms
(/ 1 (* (- (acos a)) (/ 1 a)))
25.0ms
(* (- (acos a)) (/ 1 a))

simplify517.0ms

Counts
24 → 52
Calls
24 calls:
Slowest
319.0ms
(* (* (* (- (acos a)) (- (acos a))) (- (acos a))) (* (* (/ 1 a) (/ 1 a)) (/ 1 a)))
50.0ms
(* (- (acos a)) (/ 1 a))
32.0ms
(+ (log (- (acos a))) (log (/ 1 a)))
18.0ms
(* -1 (/ a (acos a)))
15.0ms
(* -1 (/ a (acos a)))

prune375.0ms

Pruning

12 alts after pruning (10 fresh and 2 done)

Merged error: 0.0b

localize6.0ms

Local error

Found 2 expressions with local error:

0.4b
(/ (/ 1 (- (acos a))) (/ 1 a))
0.0b
(/ 1 (- (acos a)))

rewrite12.0ms

Algorithm
rewrite-expression-head
Rules
16×times-frac
15×add-cube-cbrt
15×*-un-lft-identity
15×add-sqr-sqrt
14×associate-/r*
12×div-inv
add-exp-log
associate-/l*
add-cbrt-cube
distribute-rgt-neg-in
pow1
distribute-lft-neg-in
add-log-exp
div-exp
frac-2neg
clear-num
rec-exp
associate-/l/
inv-pow
pow-flip
associate-/r/
neg-mul-1
cbrt-undiv
Counts
2 → 62
Calls
2 calls:
Slowest
8.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))
2.0ms
(/ 1 (- (acos a)))

series25.0ms

Counts
2 → 6
Calls
2 calls:
Slowest
19.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))
6.0ms
(/ 1 (- (acos a)))

simplify1.6s

Counts
58 → 68
Calls
58 calls:
Slowest
905.0ms
(/ (* (* (/ 1 (- (acos a))) (/ 1 (- (acos a)))) (/ 1 (- (acos a)))) (* (* (/ 1 a) (/ 1 a)) (/ 1 a)))
67.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))
62.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))
58.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))
52.0ms
(/ (/ 1 (- (acos a))) (/ 1 a))

prune365.0ms

Pruning

7 alts after pruning (4 fresh and 3 done)

Merged error: 0.0b

regimes73.0ms

Accuracy

0% (0.2b remaining)

Error of 0.3b against oracle of 0.0b and baseline of 0.3b

bsearch0.0ms

end0.0ms

sample1.5s

Algorithm
intervals