# Solved: wait time

Sure, here’s an example about how to use the “waitbar” function in Matlab, a function that often used to display the progress of a computational operation:

Wait time in programming always presents a significant challenge which is part of the user interface design. In Matlab, a popular computing environment for engineers and scientists, this issue is efficiently managed using a function known as ‘waitbar’. The ‘waitbar’ function primarily provides a visual representation of the progress of a computational operation for the end user. It is used in computational tasks that involve long steps, providing assurance that the task at hand is still ongoing and your program has not stalled.

## The waitbar function in MATLAB

In MATLAB, the ‘waitbar’ function creates a wait bar or progress bar GUI object showing the progress of some tasks. The function is utilized as:

``` h = waitbar(x,'message',property,value,...) ```

‘x’ defines the fractional length of the ‘waitbar’. The value varies between 0 and 1 where 0 signifies that the process has just begun and 1 indicating the completion of the task. The ‘message’ in the function is a string that appears on the dialog box depicting the task being executed. Any other GUI properties of the ‘waitbar’ can be altered using the property-value pair arguments.

## Step-by-Step: Building a Waitbar

Creating a waitbar involves initializing the waitbar, updating it in a loop, and closing it when the task is complete.

Initialization:

```h = waitbar(0,'Please wait...');
```

The existing step initializes the waitbar. ‘0’ marks the starting, and the string ‘Please wait…’ is the initial message displayed.

Update within a loop:

```for i=1:100,
% computation here %
waitbar(i/100,h)
end
```

The update happens within a loop, in this case, a ‘for’ loop spanning from 1 to 100. The ‘waitbar’ function is called at the end of each iteration with ‘i/100’ as an argument, updating the progress of the task.

Completion:

```close(h)
```

The ‘close’ function shuts down the waitbar after successful completion of the task.

## Libraries and Important Functions

Waitbar is a part of GUI utilities in MATLAB which eases the programming work without dealing much in the GUI design. Some important functions that go hand-in-hand with waitbar are ‘uicontrol’ and ‘uifigure’ for creating user interface controls and figures respectively.

## Other Approaches and Alternatives

Alternatives for ‘waitbar’ are ‘pause’ and ‘drawnow’ functions. ‘pause’ halts the program execution for a specified number of seconds, while ‘drawnow’ updates figure windows and processes pending callbacks.

This is a brief expose of the ‘waitbar’ function in MATLAB. It is crucial to note that it can significantly improve the end user’s experience when using your program, by keeping them informed about long computational tasks.

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