Reference Guide

RPL Programming Examples 2-11
Techniques used in %TILE
 FLOOR and CEIL. For an integer, FLOOR and CEIL both return that integer; for a noninteger, FLOOR and
CEIL return successive integers that bracket the noninteger.
 SORT. The SORT command sorts the list elements into ascending order.
%TILE program listing
Program: Comments:
«
SWAP SORT
Brings the list to level 1 and sorts it.
DUP SIZE
Copies the list, then finds its size.
1 + ROT %
Calculates the position of the specified percentile.
DUP2
Makes a copy of the list and the percentile.
FLOOR
Rounds the position to the lower integer.
1 MAX OVER SIZE MIN
Ensures it is between 1 and the size of the list.
GET
Gets the corresponding number.
ROT ROT
Moves the list to level 1.
CEIL
Rounds the position to the upper integer.
1 MAX OVER SIZE MIN
Ensures it is between 1 and the size of the list.
GET
Gets the corresponding number.
+ 2 /
Calculates the average of the two numbers.
»
`O %TILE K
Stores the program in %TILE.
Checksum: # 3805d
Bytes: 92.5
Example: Calculate the median of the list {8 3 1 5 2}.
!ä 8 3 1 5 2`
J50 %©TILE%
MEDIAN (Median of Statistics Data)
MEDIAN returns a vector containing the medians of the columns of the statistics data. Note that for a sorted list
with an odd number of elements, the median is the value of the center element; for a list with an even number of
elements, the median is the average value of the elements just above and below the center.
Level 1
→
Level 1
→
[ x
1
x
2
 x
m
]