Using Shift And Cumsum Functions In A Column Header - Texas Instruments TI-89 Manual Book

Using Shift and CumSum Functions in a Column Header

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
, or press
CATALOG
2 I and select it from
the List submenu.
250 Chapter 15: Data/Matrix Editor
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.
The function copies a base column and shifts it up or down by a
shift
specified number of elements. Use † to define a column header
with the syntax:
shift (column [,integer])
Number of elements to shift (positive shifts up;
negative shifts down). Default is ë1.
Column used as the base for the shift.
For example, for a two-element shift up and down:
c2=shift(c1,2)
First two elements of c1 shift up and out the top;
undefined elements shift into the bottom.
The function returns a cumulative sum of the elements in a
cumSum
base column. Use † to define a column header with the syntax:
cumSum (column)
Column used as the base for the cumulative sum
For example:
c2=cumSum(c1)
1+2
1+2+3+4
c3=shift(c1,ë2)
Shifted columns have the same
length as the base column (c1).
Last two elements of c1 shift down and out the
bottom; undefined elements shift into the top.