| Copyright | (c) Edward Kmett 2013 |
|---|---|
| License | BSD3 |
| Maintainer | Edward Kmett <[email protected]> |
| Stability | experimental |
| Portability | non-portable |
| Safe Haskell | None |
| Language | Haskell98 |
Data.HyperLogLog.Type
Contents
Description
This package provides an approximate streaming (constant space) unique object counter.
See the original paper for details: http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf
- newtype HyperLogLog p = HyperLogLog {}
- class HasHyperLogLog a p | a -> p where
- hyperLogLog :: Lens' a (HyperLogLog p)
- size :: ReifiesConfig p => HyperLogLog p -> Approximate Int64
- insert :: (ReifiesConfig s, Serial a) => a -> HyperLogLog s -> HyperLogLog s
- intersectionSize :: ReifiesConfig p => [HyperLogLog p] -> Approximate Int64
- cast :: forall p q. (ReifiesConfig p, ReifiesConfig q) => HyperLogLog p -> Maybe (HyperLogLog q)
HyperLogLog
newtype HyperLogLog p Source
Initialize a new counter:
>>>mempty :: HyperLogLog $(3)HyperLogLog {runHyperLogLog = fromList [0,0,0,0,0,0,0,0]}
Please note how you specify a counter size with the $(n)
invocation. Sizes of up to 16 are valid, with 7 being a
likely good minimum for decent accuracy.
Let's count a list of unique items and get the latest estimate:
>>>size (foldr insert mempty [1..10] :: HyperLogLog $(4))Approximate {_confidence = 0.9972, _lo = 2, _estimate = 9, _hi = 17}
Note how insert can be used to add new observations to the
approximate counter.
Constructors
| HyperLogLog | |
Fields | |
Instances
| HasHyperLogLog k (HyperLogLog k p) p | |
| Eq (HyperLogLog k p) | |
| Show (HyperLogLog k p) | |
| Generic (HyperLogLog k p) | |
| ReifiesConfig k p => Monoid (HyperLogLog k p) | |
| Serialize (HyperLogLog k p) | |
| Semigroup (HyperLogLog k p) | |
| ReifiesConfig k p => HasConfig (HyperLogLog k p) | |
| type Rep (HyperLogLog k p) |
class HasHyperLogLog a p | a -> p where Source
Methods
hyperLogLog :: Lens' a (HyperLogLog p) Source
Instances
| HasHyperLogLog k (HyperLogLog k p) p |
size :: ReifiesConfig p => HyperLogLog p -> Approximate Int64 Source
Approximate size of our set
insert :: (ReifiesConfig s, Serial a) => a -> HyperLogLog s -> HyperLogLog s Source
intersectionSize :: ReifiesConfig p => [HyperLogLog p] -> Approximate Int64 Source
cast :: forall p q. (ReifiesConfig p, ReifiesConfig q) => HyperLogLog p -> Maybe (HyperLogLog q) Source