Average Error: 3.7 → 3.2
Time: 9.2s
Precision: 64
Internal Precision: 128
\[\left(a + \left(b + \left(c + d\right)\right)\right) \cdot 2\]
\[(e^{\log_* (1 + \left(a + \left(d + \left(c + b\right)\right)\right))} - 1)^* \cdot 2\]

Error

Bits error versus a

Bits error versus b

Bits error versus c

Bits error versus d

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original3.7
Target3.8
Herbie3.2
\[\left(a + b\right) \cdot 2 + \left(c + d\right) \cdot 2\]

Derivation

  1. Initial program 3.7

    \[\left(a + \left(b + \left(c + d\right)\right)\right) \cdot 2\]
  2. Using strategy rm
  3. Applied associate-+r+2.8

    \[\leadsto \left(a + \color{blue}{\left(\left(b + c\right) + d\right)}\right) \cdot 2\]
  4. Using strategy rm
  5. Applied expm1-log1p-u3.2

    \[\leadsto \color{blue}{(e^{\log_* (1 + \left(a + \left(\left(b + c\right) + d\right)\right))} - 1)^*} \cdot 2\]
  6. Using strategy rm
  7. Applied *-un-lft-identity3.2

    \[\leadsto (e^{\color{blue}{1 \cdot \log_* (1 + \left(a + \left(\left(b + c\right) + d\right)\right))}} - 1)^* \cdot 2\]
  8. Final simplification3.2

    \[\leadsto (e^{\log_* (1 + \left(a + \left(d + \left(c + b\right)\right)\right))} - 1)^* \cdot 2\]

Reproduce

herbie shell --seed 2019005 +o rules:numerics
(FPCore (a b c d)
  :name "Expression, p6"
  :pre (and (<= -14 a -13) (<= -3 b -2) (<= 3 c 3.5) (<= 12.5 d 13.5))

  :herbie-target
  (+ (* (+ a b) 2) (* (+ c d) 2))

  (* (+ a (+ b (+ c d))) 2))

Details

Time bar (total: 7.0s)Debug log

sample59.0ms

Algorithm
intervals

simplify262.0ms

Counts
1 → 1
Calls

1 calls. Slowest were:

262.0ms
(* (+ a (+ b (+ c d))) 2)

prune5.0ms

Pruning

1 alts after pruning (1 fresh and 0 done)

Merged error: 3.7b

localize13.0ms

Local error

Found 2 expressions with local error:

2.4b
(+ a (+ b (+ c d)))
0.5b
(+ b (+ c d))

rewrite2.0ms

Algorithm
rewrite-expression-head
Counts
2 → 26
Calls

2 calls. Slowest were:

1.0ms
(+ a (+ b (+ c d)))
1.0ms
(+ b (+ c d))

series38.0ms

Counts
2 → 6
Calls

2 calls. Slowest were:

22.0ms
(+ a (+ b (+ c d)))
17.0ms
(+ b (+ c d))

simplify55.0ms

Counts
7 → 32
Calls

7 calls. Slowest were:

15.0ms
(+ b (+ c d))
10.0ms
(+ b (+ c d))
7.0ms
(+ a (+ b c))

prune287.0ms

Pruning

8 alts after pruning (8 fresh and 0 done)

Merged error: 2.1b

localize9.0ms

Local error

Found 1 expressions with local error:

2.4b
(+ a (+ (+ b c) d))

rewrite3.0ms

Algorithm
rewrite-expression-head
Counts
1 → 13
Calls

1 calls. Slowest were:

3.0ms
(+ a (+ (+ b c) d))

series23.0ms

Counts
1 → 3
Calls

1 calls. Slowest were:

23.0ms
(+ a (+ (+ b c) d))

simplify20.0ms

Counts
3 → 16
Calls

3 calls. Slowest were:

7.0ms
(+ b (+ c d))
7.0ms
(+ a (+ b c))
6.0ms
(+ b (+ c d))

prune162.0ms

Pruning

9 alts after pruning (9 fresh and 0 done)

Merged error: 1.8b

localize9.0ms

Local error

Found 3 expressions with local error:

2.4b
(+ a (+ (+ b c) d))
0.1b
(expm1 (log1p (+ a (+ (+ b c) d))))
0.1b
(log1p (+ a (+ (+ b c) d)))

rewrite3.0ms

Algorithm
rewrite-expression-head
Counts
3 → 35
Calls

3 calls. Slowest were:

3.0ms
(+ a (+ (+ b c) d))
0.0ms
(log1p (+ a (+ (+ b c) d)))
0.0ms
(expm1 (log1p (+ a (+ (+ b c) d))))

series318.0ms

Counts
3 → 9
Calls

3 calls. Slowest were:

187.0ms
(expm1 (log1p (+ a (+ (+ b c) d))))
100.0ms
(log1p (+ a (+ (+ b c) d)))
31.0ms
(+ a (+ (+ b c) d))

simplify1.0s

Counts
10 → 44
Calls

10 calls. Slowest were:

447.0ms
(- (+ (/ 1 a) (log -1)) (+ (* 1/2 (/ 1 (pow a 2))) (log (/ -1 a))))
254.0ms
(- (/ 1 a) (+ (* 1/2 (/ 1 (pow a 2))) (log (/ 1 a))))
186.0ms
(- (+ (exp (- (log -1) (log (/ -1 a)))) (/ (exp (- (log -1) (log (/ -1 a)))) a)) 1)

prune529.0ms

Pruning

16 alts after pruning (16 fresh and 0 done)

Merged error: 1.8b

localize15.0ms

Local error

Found 3 expressions with local error:

2.4b
(+ a (+ (+ b c) d))
0.1b
(expm1 (* 1 (log1p (+ a (+ (+ b c) d)))))
0.1b
(log1p (+ a (+ (+ b c) d)))

rewrite6.0ms

Algorithm
rewrite-expression-head
Counts
3 → 35
Calls

3 calls. Slowest were:

5.0ms
(+ a (+ (+ b c) d))
0.0ms
(expm1 (* 1 (log1p (+ a (+ (+ b c) d)))))
0.0ms
(log1p (+ a (+ (+ b c) d)))

series288.0ms

Counts
3 → 9
Calls

3 calls. Slowest were:

153.0ms
(expm1 (* 1 (log1p (+ a (+ (+ b c) d)))))
113.0ms
(log1p (+ a (+ (+ b c) d)))
22.0ms
(+ a (+ (+ b c) d))

simplify813.0ms

Counts
11 → 44
Calls

11 calls. Slowest were:

334.0ms
(- (+ (/ 1 a) (log -1)) (+ (* 1/2 (/ 1 (pow a 2))) (log (/ -1 a))))
169.0ms
(- (/ 1 a) (+ (* 1/2 (/ 1 (pow a 2))) (log (/ 1 a))))
152.0ms
(- (+ (exp (- (log -1) (log (/ -1 a)))) (/ (exp (- (log -1) (log (/ -1 a)))) a)) 1)

prune493.0ms

Pruning

16 alts after pruning (15 fresh and 1 done)

Merged error: 1.8b

regimes957.0ms

Accuracy

0% (1.2b remaining)

Error of 3.2b against oracle of 2.0b and baseline of 3.2b

bsearch2.0ms

end0.0ms

sample1.6s

Algorithm
intervals