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Diffstat (limited to 'docs/commands/hyperloglog.md')
| -rw-r--r-- | docs/commands/hyperloglog.md | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/docs/commands/hyperloglog.md b/docs/commands/hyperloglog.md index 7421fce..6f8e849 100644 --- a/docs/commands/hyperloglog.md +++ b/docs/commands/hyperloglog.md @@ -15,11 +15,11 @@ PFINIT key precison [TIME window-milliseconds] - precision -- The data of the HyperLogLog is stored in an array of m registers. m is 2^precision, e.g. precision=4, m=16. The precision should be between 4 to 16. - TIME -- Optional. Creates a time-limited HyperLogLog. 'window-milliseconds' specifies the duration of the time window in milliseconds. This mode allows HyperLogLog to estimate the cardinality of items within the range (now - window-milliseconds, now]. -The HyperLogLog use 6 bits per register, so for precision=14, the data structure is ~12KB (2^14*6/8 bytes). The relative error of HLL is 1.04/sqrt(m). +The HLL has a relative error of 1.04/sqrt(m), where m is the number of registers. The SwarmKV HLL implementation uses 6 bits per register, so for a key with precision=14, the memory size is ~12KB (2^14*6/8 bytes), and with a standard error of 0.81%. Return -- Simple String Reply: OK if the bloom filter created successfully. +- Simple String Reply: OK if the HyperLogLog created successfully. - Empty Array if key already exists. Examples |