Texas Instruments PLUS TI-89 - Manual (Page 267)

250 Chapter 15: Data/Matrix Editor
15DATAMA.DOC TI-89/TI-92 Plus: Data/Matrix Editor (English) Susan Gullord Revised: 02/23/01 1:10 PM Printed: 02/23/01 2:17 PM Page 250 of 16
The shift function copies a base column and shifts it up or down by a
specified number of elements. Use † to define a column header
with the syntax:
shift ( column [, integer ])
For example, for a two-element shift up and down:
The cumSum function returns a cumulative sum of the elements in a
base column. Use † to define a column header with the syntax:
cumSum ( column )
For example:
Using Shift and CumSum Functions in a Column Header
When defining a column header, you can use the shift and
cumSum functions as described below. These descriptions
differ slightly from Appendix A. This section describes how to
use the functions in the Data/Matrix Editor. Appendix A gives a
more general description for the Home screen or a program.
Using the Shift
Function
Note: To enter “shift”, type it
from the keyboard or select
it fromthe CATALOG.
Using the CumSum
Function
Note: To enter “cumSum”,
type it, select it from the
CATALOG
, or press
2 I and select it from
the List submenu.
Column used as the base for the shift.
Column used as the base for the cumulative sum
Number of elements to shift (positive shifts up;
negative shifts down). Default is
ë 1.
c2=shift(c1,2)
c3=shift(c1, ë 2)
Shifted columns have the same
length as the base column (c1).
First two elements of c1 shift up and out the top;
undefined elements shift into the bottom.
Last two elements of c1 shift down and out the
bottom; undefined elements shift into the top.
c2=cumSum(c1)
1+2+3+4
1+2