TDIGEST.BYREVRANK

Syntax
TDIGEST.BYREVRANK key reverse_rank [reverse_rank ...]
Available in:
Redis Open Source / Bloom 2.4.0
Time complexity:
O(N) where N is the number of reverse ranks specified.
ACL categories:
@tdigest, @read,

Returns, for each input reverse rank (revrank), an estimation of the floating-point value with that reverse rank. Multiple estimations can be retrieved in a single call.

Required arguments

key

is the key name of an existing t-digest sketch.

revrank

Reverse ranks for which the values should be retrieved.

0 is the reverse rank of the value of the largest observation.

n-1 is the reverse rank of the value of the smallest observation, where n denotes the number of observations added to the sketch.

Examples

redis> TDIGEST.CREATE t COMPRESSION 1000
OK
redis> TDIGEST.ADD t 1 2 2 3 3 3 4 4 4 4 5 5 5 5 5
OK
redis> TDIGEST.BYREVRANK t 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
 1) "5"
 2) "5"
 3) "5"
 4) "5"
 5) "5"
 6) "4"
 7) "4"
 8) "4"
 9) "4"
10) "3"
11) "3"
12) "3"
13) "2"
14) "2"
15) "1"
16) "-inf"

Return information

One of the following:

  • Array of bulk strings as floating-points, populated with value_1, value_2, ..., value_R:
    • an accurate result when rank is 0, the value of the largest observation.
    • an accurate result when rank is n-1, the value of the smallest observation, where n denotes the number of observations added to the sketch.
    • inf when rank is equal to n or larger than n.
    • nan for all ranks when the given sketch is empty.
  • Simple error reply in these cases: the given key does not exist or is of an incorrect type, rank parsing errors, or an incorrect number of arguments.
RATE THIS PAGE
Back to top ↑