Graphics |

**Example -- Specifying a Data Source**

Plot objects have properties that enable you to specify the source of the data that defines the object. For example, you can specify a workspace variable name or a MATLAB expression as the value of the `XDataSource`

, `YDataSource`

, or `ZDataSource`

property for a line in a plot (i.e., a lineseries object). You can then use the Property Editor to change the variable name or alter the expression, and the plot is updated to reflect the change.

**Creating the Graph**

First define two variables by issuing these statements in the command window.

Next plot `t`

vs. the expression `exp(-alpha*t).*sin(.5*t)`

using the `plot`

function or the plot tools.

**Varying the Data Source**

After creating the graph, you can use the Property Editor to couple the plotted line to the MATLAB expression.

- Double-click on the plotted line to display its property panel.
- Enter the MATLAB expression in the
**Y Data Source**text field.

You can now modify the expression in the **Y Data Source** text field and observe how the graph changes. After changing the text, click the **Refresh Data** button to update the data.

In the following picture, `alpha`

is no longer negated, so the function grows instead of decays. Also the period has been shortened by changing `sin(.5*t)`

to `sin(1.5*t)`

.

**Data Sources for Multiobject Graphs**

Suppose you create a line graph from matrix data. For example,

Because MATLAB creates one lineseries object for each column of `z`

, the following is true.

The data source for `h(1)`

is `z(:,1)`

.

The data source for `h(2)`

is `z(:,2)`

.

The data source for `h(n)`

is `z(:,n)`

.

Example -- Plotting Workspace Variables | Example -- Generating M-Code to Reproduce a Graph |

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