MATLAB Programming Fundamentals - MathWorks

Share Data Between Workspaces

In this section...

“Introduction” on page 20-11

“Best Practice: Passing Arguments” on page 20-11

“Nested Functions” on page 20-12

“Persistent Variables” on page 20-12

“Global Variables” on page 20-13

“Evaluating in Another Workspace” on page 20-14

Introduction

This topic shows how to share variables between workspaces or allow them to persist

between function executions.

In most cases, variables created within a function are local variables known only within

that function. Local variables are not available at the command line or to any other

function. However, there are several ways to share data between functions or

workspaces.

Best Practice: Passing Arguments

The most secure way to extend the scope of a function variable is to use function input

and output arguments, which allow you to pass values of variables.

For example, create two functions, update1 and update2, that share and modify an

input value. update2 can be a local function in the file update1.m, or can be a function

in its own file, update2.m.

function y1 = update1(x1)

y1 = 1 + update2(x1);

function y2 = update2(x2)

y2 = 2 * x2;

Call the update1 function from the command line and assign to variable Y in the base

workspace:

Share Data Between Workspaces