percentile_tdigest()

Calculates the percentile result from the tdigest results (which was generated by tdigest() or tdigest_merge())

Syntax

percentile_tdigest(Expr, Percentile1 , typeLiteral)

Arguments

  • Expr: Expression that was generated by tdigest or tdigest_merge().
  • Percentile is a double constant that specifies the percentile.
  • typeLiteral: An optional type literal (for example, typeof(long)). If provided, the result set will be of this type.

Returns

The percentile value of each value in Expr.

Tips

  • If the type was provided, the result will be a column of the same type provided with the results of the percentile. In this case, all tdigest functions must be of that type.

  • If Expr includes tdigest functions of different types, don't provide the type. The result will be of type dynamic. See below examples.

Examples

StormEvents
| summarize tdigestRes = tdigest(DamageProperty) by State
| project percentile_tdigest(tdigestRes, 100, typeof(int))
percentile_tdigest_tdigestRes
0
62000000
110000000
1200000
250000
StormEvents
| summarize tdigestRes = tdigest(DamageProperty) by State
| union (StormEvents | summarize tdigestRes = tdigest(EndTime) by State)
| project percentile_tdigest(tdigestRes, 100)
percentile_tdigest_tdigestRes
[0]
[62000000]
["2007-12-20T11:30:00.0000000Z"]
["2007-12-31T23:59:00.0000000Z"]