HP 40G manual Variables and memory management, Introduction

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Variables and memory management

Introduction

The HP 39G/40G has approximately 232K of user memory. The calculator uses this memory to store variables, perform computation, and store history.

A variable is an object that you create in memory to hold data. The HP 39G/40G has two types of variables, home variables and aplet variables.

•Home variables are available in all aplets. For example, you can store real numbers in variables A to Z and complex numbers in variables Z0 to Z9. These can be numbers you have entered, or the results of calculations. These variables are available within all aplets and within any programs.

•Aplet variables apply only to a single aplet. Aplets have specific variables allocated to them which vary from aplet to aplet.

You use the calculator’s memory to store the following objects:

•copies of aplets with specific configurations

•new aplets that you download

•aplet variables

•home variables

•variables created through a catalog or editor, for example a matrix or a text note

•programs that you create.

You can use the Memory Manager (>6+,)7@MEMORY) to view the amount of memory available. The catalog views, which are accessible via the Memory Manager, can be used to transfer variables such as lists or matrices between calculators.

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