Using The Cumsum Function - Texas Instruments TITANIUM TI-89 User Manual

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To enter shift, type it from the keyboard or select it from the CATALOG.
Note:

Using the CumSum Function

Using the CumSum Function Using the CumSum Function Using the CumSum Function
The function returns a cumulative sum of the elements in a base column. Use
cumSum
† to define a column header with the syntax:
cumSum (column)
For example:
To enter
Note: cumSum
select it from the List submenu.
Data/Matrix Editor
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c2=shift(c1,2)
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c3=shift(c1, 2)
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Shifted columns have the same length as the base
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Last two elements of c1 shift down and out the
bottom; undefined elements shift into the top.
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First two elements of c1 shift up and out the top;
undefined elements shift into the bottom.
Column used as the base for the cumulative sum.
, type it, select it from the CATALOG, or press 2 I and
c2=cumSum(c1)
1+2
1+2+3+4
534