Algorithm (Workflow)

This function, plotannotationtopleft, is designed to create a text annotation in the top-left corner of the current axis in a MATLAB figure. It is part of the SolidGeometry library and was introduced in version 5.0.

Input Parameters

• str: A string that contains the text to be displayed in the annotation. It can include special characters like \n for new lines, \b for backspace, and \r for carriage return.
• vargs: A list of optional parameters that can be used to customize the appearance of the annotation, such as font size, color, etc.

Output

• t: A handle to the created textbox annotation, which can be used for further customization or manipulation.

Algorithm Steps

1. The function begins by extracting the str parameter from the input arguments using the getfuncparams function. If no string is provided, a default string is used.
2. The remaining input arguments are stored in vargs for further use.
3. If str is not already a cell array, it is converted into one. Special characters in the string are replaced with their corresponding ASCII characters.
4. The position of the current axis is obtained using get(gca, 'Position').
5. An annotation is created using the annotation function with the specified string and optional parameters. The annotation is aligned to the left.
6. The position of the annotation is adjusted to ensure it appears in the top-left corner of the axis. This is done by calculating the new position based on the axis and annotation sizes.
7. The position of the annotation is set using set(t, 'Position', np), and the figure is updated with drawnow.

Example Usage

An example of how to use this function is provided:

plotannotationdelete; 
plotannotationtopleft('Hello world\nthe quick brows'); 
shg

This example deletes any existing annotations, creates a new annotation with the specified text, and then brings the figure window to the front.