A streaming algorithm is an algorithm that receives its input one element at a time.
Questions tagged [streaming-algorithm]
6 questions
6
votes
1 answer
Find top k visiting URL for last day, or last hour, or last minute?
The original question is given file containing 5GB URL being visited last day, find the top k frequent URL. The problem can be solved by using hash map to count the occurrences of distinct URL and find top k with the help of min heap, taking a O(n…
user1941469
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3
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1 answer
How does count min sketch find the most frequent item in a stream? - Heavy Hitters
Count min sketch uses different hash functions to map elements in the stream to the hash function. How to map back from the sketch to find the most frequent item? Considering that enough elements have been passes(millions) and we don’t know the…
user3508140
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1
vote
1 answer
Sliding window set
I'm looking for a way to efficiently maintain a set of values from a 1 minute sliding window from a given datastream (~100k values/sec).
I'm looking for solution with at most logarithmic insertion time (since basic time-ordered vector of values has…
discobot
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0
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O(n) Heavy-Hitters with O(1/epsilon) space?
I know of the following algorithm for heavy-hitters:
Algorithm findHeavyHitters(epsilon, inputStream)
integer k = ceiling(1 / epsilon) - 1
initialize hashmap H of size k
while an item i from the input stream arrives:
if H[i]…
fluffychaos
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0
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Siddhi CEP - events which were not joined in a sliding window
I have two streams, streamA and streamB. Each of streamA has an ID and matching event in streamB will have same ID.
I want to know from streamA which IDs have not come in streamB after a sliding window of lets say, 1 minute.
I have tried this, but…
spiralarchitect
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Computing percentiles using a fixed amount of memory
I have a stream of int values arriving at a certain rate. Every 5 minutes, I'd like to compute some percentiles from the values, and start over.
The problem: I don't want to waste too much memory, so I'd like to keep only a few KBs for the values.…
user1424934
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