| Navigation: Templates > Guide to all Templates > Additional Libraries and Templates > Statistics Library >====== PERCENTILE (pth percentile value of a set) ====== |    |
PERCENTILE(dataset,percentile)
| PERCENTILE | Returns a value that divides an ordered numeric data set into two portions of specified relative size. |
| dataset | The label of a QUEUE with its first component field defined as a REAL. |
| percentile | A numeric constant or variable containing an integer value in the range: 1 >= p <;= 99 . |
PERCENTILE computes a value such that at most pth% of the set's values are less than the amount, and at most 100 - pth% of the set's values are greater than the amount. The function operates on the numeric set defined by all the entries in the first component of the designated QUEUE (dataset).
For example, given the data set: [1,2,3,4,5,6], the 50th Percentile value is 3.5.
In general, the PERCENTILE function is only meaningful when the number of elements in the data set is large (ie. greater than 20).
See also:
The passed data set does not have to be sorted. The function copies the passed set. The passed data set is unchanged.
Return DataType: REAL
Example:
StatSetX QUEUE,PRE()
X REAL
END
PercentileOfX REAL
DividePoint REAL(90)
CODE
FREE(StatSetX) !free the QUEUE
CLEAR(STADAT:RECORD) !clear the record buffer
STADAT:Id = STA:Id !prime the record buffer
STADAT:ItemNumber = 1
SET(STADAT:KeyIdItemNumber,STADAT:KeyIdItemNumber !position file pointer
LOOP !load the QUEUE
NEXT(StatisticsData) !read next record
IF ERRORCODE() OR STADAT:Id NOT = STA:Id
BREAK
ELSE
StatSetX:X = STADAT:X !load the QUEUE buffer
ADD(StatSetX) !add to the QUEUE
END
END
PercentileOfX = PERCENTILE(StatSetX,DividePoint) !call PERCENTILE