Property	Value
Hex Value	`$EFA6`
Categories
Localizations	FR: `parmorceaux(`

`piecewise(`

Overview

New piecewise function to support entry of functions as they are seen in textbook. This command can be found in » MATH B:piecewise(

Comment:CE OS 5.3+

Availability: Token available everywhere.

Syntax

piecewise(

Location

math

Description

The piecewise( command is a new addition in the release of OS 5.3 for the TI-84 Plus CE. As implied, it allows for the graphing of piecewise functions in the Y= editor. The example code demonstrates how this works from within a program.

:ClrDraw
:Input "Y1=",Str1
:Input "Y2=",Str2
:Str1→Y1
:Str2→Y2
:FnOff
:"piecewise(Y1,X≥0,Y2,X<0→Y3
:DispGraph

Advanced Uses

One use of the piecewise( function is to evaluate an expression for a given value of X. For example:

:piecewise(X²+2,X≥0

This code will return the value of the expression if X≥0. So if X=0, then the program will return a value of 2. If X=3, it will return a value of 11. If X=-5, it will return an error.

Optimization

This command can simplify and compact the usage of piecewise expressions in programs. If you have less than 6 conditions that will never overlap, and they all affect a single variable, you can use the piecewise( command to make your code smaller, as shown below. Beware of comparability, though.

:If X<2
:Then
:4.5X→N
:Else
:8X+3→N
:End
can be
:piecewise(4.5X,X<2,8X+3,X≥2→N

Error Conditions

ERR:INVALID is thrown if expressions are not defined.
ERR:DATA TYPE is thrown if a quotation mark is not placed before a piecewise command that is to be stored to an equation variable.

History

Calculator	OS Version	Description
TI-84+CE	5.3.0	Added

Authors: Adrien Bertrand

piecewise(