RANK

The RANK function computes the rank of values in a numeric expression.

Return Value

DECIMAL

Syntax

RANK(expression method [BASEDON dimension-list])

Arguments

expression: The numeric expression for which rankings are to be computed.
method: The method to use in computing the rank of the values in expression. The method argument can be one of the following keywords. See also "Results of Method Values".

Table 20-1 Methods for Computing RANK

Method	Description
MIN	Identical values get the same minimum rank.
MAX	Identical values get the same maximum rank.
AVERAGE	Identical values get the same average rank.
PACKED	Identical values get the same rank but the results are packed into consecutive integers.
UNIQUE	All values get a unique rank; for identical values the rank is arbitrary.
PERCENTILE	Values are ranked from 1 to 100, based on the relative frequency of their occurrence in the expression.
DECILE	Values are ranked from 1 to 10, based on the relative frequency of their occurrence in the expression.
QUARTILE	Values are ranked from 1 to 4, based on the relative frequency of their occurrence in the expression.

BASEDON dimension-list: An optional list of one or more of the dimensions of expression to include in the ranking. When you do not specify the dimensions, then RANK bases the ranking on all of the dimensions of expression.

Notes

Results of Method Values

This note describes the results of the different methods of ranking values. The results are based on the sales2 variable, which is described in "Ranking Values", with the geography dimension limited to G2 as the following statements demonstrate.

LIMIT geography TO 'G2'
SORT items D sales2
REPORT DOWN geography sales2

The preceding statements produce the following output.

------------------------SALES2------------------------
               ------------------------ITEMS-------------------------
GEOGRAPHY        ITEM4      ITEM2      ITEM3      ITEM1      ITEM5
-------------- ---------- ---------- ---------- ---------- ----------
G2                  25.00      20.00      20.00      15.00       7.00

Table 20-2, "Results of Different Methods of Ranking " shows the results of the different methods of ranking that are produced by a statement of the form

REPORT DOWN geography RANK(sales2 MIN BASEDON items)

with the different method keywords substituted for MIN.

Table 20-2 Results of Different Methods of Ranking

Methods	(ITEM4, G2) = 25	(ITEM2, G2) = 20	(ITEM3, G2) = 20	(ITEM1,G2) = 15	(ITEM5,G2) = 7
MIN	1	2	2	4	5
MAX	1	3	3	4	5
AVERAGE	1	2.5	2.5	4	5
PACKED	1	2	2	3	4
UNIQUE	1	2	3	4	5
PERCENTILE	100	62	62	25	1
DECILE	10	7	7	3	1
QUARTILE	4	3	3	1	1

Note that the value that is returned by the UNIQUE method for Item2 and Item3 can be either 2 or 3, since the RANK function randomly assigns a unique rank for identical values in the expression.

Examples

Example 20-3 Ranking Values

These examples use the following geography and items dimensions and sales2 variable.

DEFINE geography DIMENSION TEXT 
MAINTAIN geography ADD 'g1' 'g2' 'g3'
DEFINE items DIMENSION TEXT
MAINTAIN items ADD 'Item1' 'Item2' 'Item3' 'Item4' 'Item5'
DEFINE sales2 DECIMAL <geography items>

Assume the SALES2 variable has the following data values.

-------------SALES2-------------
               -----------GEOGRAPHY------------
ITEMS              g1         g2         g3
-------------- ---------- ---------- ----------
Item1               30.00      15.00      12.00
Item2               10.00      20.00      18.00
Item3               15.00      20.00      24.00
Item4               30.00      25.00      25.00
Item5                  NA       7.00      21.00

This statement reports the results of using the MIN method to rank the sales2 values based on the items dimension.

report rank(sales2 min basedon items)

The preceding statement produces the following output.

-RANK(SALES2 MIN BASEDON ITEMS)-
               -----------GEOGRAPHY------------
ITEMS              g1         g2         g3
-------------- ---------- ---------- ----------
Item1                1.00       4.00       5.00
Item2                4.00       2.00       4.00
Item3                3.00       2.00       2.00
Item4                1.00       1.00       1.00
Item5                  NA       5.00       3.00

This statement reports the results of using the MIN method to rank the sales2 values based on the geography dimension.

REPORT RANK(sales2 MIN BASEDON geography)

The preceding statement produces the following output.

----RANK(SALES2 MIN BASEDON-----
               -----------GEOGRAPHY)-----------
               -----------GEOGRAPHY------------
ITEMS              g1         g2         g3
-------------- ---------- ---------- ----------
Item1                1.00       2.00       3.00
Item2                3.00       1.00       2.00
Item3                3.00       2.00       1.00
Item4                1.00       2.00       2.00
Item5                  NA       2.00       1.00

This statement reports the results of using the MIN method to rank the sales2 values based on all of its dimensions.

REPORT RANK(sales2, MIN)

The preceding statement produces the following output.

-------RANK(SALES2, MIN)--------
               -----------GEOGRAPHY------------
ITEMS              g1         g2         g3
-------------- ---------- ---------- ----------
Item1                1.00      10.00      12.00
Item2               13.00       7.00       9.00
Item3               10.00       7.00       5.00
Item4                1.00       3.00       3.00
Item5                  NA      14.00       6.00