Creating Macros - Texas Instruments TI-89 User Manual

Creating Macros

Introduction to
Creating Macros
Rules for Creating
Macros
TI-89 / TI-92 Plus / Voyage™ 200 PLT Cabri Geometry App
The toolbar menu contains the tools for
Construction
constructing macros.
The
Macro Construction
constructing macros in the Geometry application. A macro is a
sequence of interdependent constructions. Macros are useful for
creating new tools that construct unique objects or perform
repetitive tasks.
A macro constructs "final" objects based on "initial" objects.
Intermediate objects are not constructed. This feature allows for
easy construction of complex figures and is the primary method for
constructing fractals. You can save macros for later use. Macros are
saved automatically with any construction in which they are used.
The number of objects created by a macro is limited only by
available system memory.
Rule
¦
Initial objects must allow
for the construction of
all final objects.
¦
An object cannot exist
without the points that
define it.
¦
When you select Define
, a macro generates
Macro
its final objects with the
object's existing
attributes.
¦
Comments and labels
cannot be defined as
final objects.
¦
The location of an
arbitrary point on an
object is determined by
random-number
generation.
¦
The order that initial
objects are used depends
upon the similarity of
their types.
menu item contains the tools for
Explanation
Final objects are determined by the
initial objects. A macro must respect
the logical structure of the figure as it
was constructed.
For example, a triangle cannot exist
without its vertices. Therefore, when
you select an object as an initial
object, the macro is able to refer to
the points that define the object.
You can change these attributes
during an intermediate step before
you select
Define Macro
you can hide objects (using
in the menu that were
Display
selected as initial objects.
Macros are intended as general
purpose construction tools, like those
in the
Construction
select measurements and numerical
values as final objects, but any text
attached will not be duplicated when
the macro executes.
The position of the point will be
uncertain if it is selected as a final
object and may result in an
incorrectly defined macro.
For example, lines and circles are
different types, and they are not used
in any order. When they are the same
type, the macro uses them in the
order in which they were selected as
initial objects.
. In this way,
Hide/Show
menu. You can
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