Maintenance script: Automated superscript correction

2016-02-24T22:25:59Z

Automated superscript correction

← Older revision		Revision as of 22:25, 24 February 2016
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	For a matrix, if you want to sum up the rows instead of the columns, use the ^^T^^ ([[TI-BASIC:Transpose\|Transpose]]) command.		For a matrix, if you want to sum up the rows instead of the columns, use the <sup>T</sup> ([[TI-BASIC:Transpose\|Transpose]]) command.

	= Related Commands =		= Related Commands =

	* [[TI-BASIC:Deltalist\|ΔList(]]		* [[TI-BASIC:Deltalist\|ΔList(]]
	* ^^T^^ ([[TI-BASIC:Transpose\|Transpose]])[[Category:TI-BASIC]]		* <sup>T</sup> ([[TI-BASIC:Transpose\|Transpose]])[[Category:TI-BASIC]]
	[[Category:TIBD]]		[[Category:TIBD]]

Maintenance script: Initial automated import

2016-02-24T18:40:01Z

Initial automated import

New page

{{Template:TI-BASIC:Command
|picture=CUMSUM.GIF
|summary=Calculates cumulative sums of a list or of the columns of a matrix.
|syntax=cumSum(''list or matrix'')
|location=Press:
# 2nd LIST to access the list menu.
# RIGHT to access the OPS submenu.
# 6 to select cumSum(, or use arrows.

Alternatively, press:
# MATRX (TI-83) or 2nd MATRX (TI-83+ or higher) to access the matrix menu.
# RIGHT to access the MATH submenu.
# 0 to select cumSum(, or use arrows.
|compatibility=TI-83/84/+/SE
|size=2 bytes
}}

cumSum( calculates the cumulative sums of a list, or of the columns of a matrix, and outputs them in a new list or matrix variable.

For a list, this means that the Nth element of the result is the sum of the first N elements of the list:

cumSum({1,3,5,7,9})
{1 4 9 16 25}

For a matrix, cumSum( is applied to each column in the same way as it would be for a list (but numbers in different columns are never added):

[[0,1,1][0,1,3][0,1,5][0,1,7]]
[[0 1 1]
[0 1 3]
[0 1 5]
[0 1 7]]
cumSum(Ans)
[[0 1 1]
[0 2 4]
[0 3 9]
[0 4 16]]

= Advanced Uses =

The [[TI-BASIC:Deltalist|ΔList(]] command is very nearly the inverse of the cumSum( command - it calculates the differences between consecutive elements. For any list, ΔList(cumSum(''list'')) will return the same list, but without its first element:

ΔList(cumSum({1,2,3,4,5,6,7}))
{2 3 4 5 6 7}

Removing the first element would otherwise be a difficult procedure involving the [[TI-BASIC:Seq_List|seq(]] command, so this is a useful trick to know.

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For a matrix, if you want to sum up the rows instead of the columns, use the ^^T^^ ([[TI-BASIC:Transpose|Transpose]]) command.

= Related Commands =

* [[TI-BASIC:Deltalist|ΔList(]]
* ^^T^^ ([[TI-BASIC:Transpose|Transpose]])[[Category:TI-BASIC]]
[[Category:TIBD]]

TI-BASIC:Cumsum - Revision history

Maintenance script: Automated superscript correction

Maintenance script: Initial automated import