<p>
    The appearance of the main (first) panel is:<br><br>
    <img src="images/ltpdagui_1.png" alt="The GUI appearance" border="1"><br><br>
    
    
    <h2>Access and selection control</h2><hr>
    In the upper part of the panel is shown the username typed in by the user when the LTPDA GUI was started.<br>
    If the login field was left empty the GUI will consider the anonymous '<tt>JohnDoe</tt>' user; the password field in this case
    has been ignored, was it empty or not.<br><br>

    This username is used to identify the current user of the system, and it's stored into the annotation of every analysis created
    by the GUI, clicking on the '<tt>New model</tt>' button.<br><br>
    
    Is possible to change the active user clicking on the '<tt>Login/Logout</tt>' button; this is to be used when:<br>
    <ul>
 		<li>The username do not respect the current active user of the system.<br></li>
  	    <li>The username and/or password typed in aren't valid credentials to connect a LTPDA Repository,
            and the user wants to submit/retrieve something.<br></li>
  	    <li>The current user is leaving the computer, to prevent other users to submit by mistake personal objects to a
            repository with a wrong account; this would make difficult to keep results traceable.<br></li>
	</ul>
    <br><br>
    On the right the GUI shows the currently active model, if the selected model is a valid LTPDA one. 'Valid' LTPDA models are
    those created by the GUI, thus containing the short annotation with the author's name, time and date of creation and so on.
    If the selected model isn't recognized by the GUI '<tt>None</tt>' will be shown here, and no selection control will be performed
    upon what the user clicks inside that model.
    <br><br>

    <h2>Analysis control panel</h2><hr><br>
    This contains 3 buttons, all devoted to the control of LTPDA Simulink model files.
    <ul>
 		<li>'<b><tt>New model</tt></b>': it creates an empty valid LTPDA Simulink model. The annotation inside will be created
            automatically to respect the current user, time and date, IP address, operative system running and MATLAB/LTPDA
            versions.<br></li>
  	    <li>'<b><tt>Open model</tt></b>': similarly to the common '<tt>Open</tt>' command in Simulink, this button loads an existing Simulink
            file from disk. If the file contains a valid LTPDA model, then the GUI will perform the selection check when it's
            selected.<br></li>
  	    <li>'<b><tt>Save model</tt></b>': lets the user to save the currently selected model. Unlike the common '<tt>Save</tt>' command in
            Simulink this will prompt the user with the assigned filename (username + time/date of creation) and the predefined
            folders for analyses, if any was set in the <tt>ltpda_startup</tt> file. Anyway, the user can freely rename this to
            any name, withstanding the common Simulink filename limitations.<br></li>
	</ul><br>
    
    <h2>Data control panel</h2><hr><br>
    Containing 9 buttons and the summary of the Input array, this part is devoted to the control of Input objects (i.e., data
    created by the user or generated inside a previous analysis run).<br>
   	<ul>
	    <li>'<b><tt>Load</tt></b>': to load data from ASCII file (to be converted into an AO), or from .MAT or .XML files.<br>
            If the selected MAT or XML file contains any valid LTPDA object, this is imported into the Input array.<br></li>
  	    <li>'<b><tt>Create</tt></b>': <i>Reserved for future use.</i><br></li>
  	    <li>'<b><tt>Edit</tt></b>': <i>Reserved for future use.</i><br></li>
   		<li>'<b><tt>Remove</tt></b>': to remove the selected object(s) from the Input array. The numbering of the
            remaining objects is not altered, to prevent problems in the indexing of objects into the analysis models opened.<br></li>
  	    <li>'<b><tt>Explore</tt></b>': to pass the selected object(s) to the <tt>ltpda_explorer</tt>, to explore them
            into an expandable and browsable window.<br></li>
  	    <li>'<b><tt>Export to workspace</tt></b>': to save the selected object(s) into the MATLAB workspace. The name of these objects
            will be automatically set.<br></li>
  	    <li>'<b><tt>Clear input</tt></b>': to clear the entire Input array.<br></li>
  	    <li>'<b><tt>Save workspace</tt></b>': even if this button is situated only inside the main panel, the <tt>Save workspace</tt>
            function it recalls affects not only the Input array, but the Output array too. It's meant as a solution to capture
            the entire current status of the LTPDA GUI, saving it into a .MAT file on disk.<br></li>
  	    <li>'<b><tt>Load workspace</tt></b>': as the <tt>Save workspace</tt> button, it lets the user to load from a .MAT file on
            disk the entire saved status of the Input and Output arrays. The loaded contents are appended to the existing arrays
            in memory.<br></li>
	</ul><br>
        <img src="images/ltpdagui_2.png" alt="The info panel" border="1"><br><br>
    The central part of the window contains two boxes: on the left a list representing the contents of the Input array, on the right
    the details of the object currently selected in the list aside.<br>
    Note this will list only LTPDA objects: if any function/block in the analysis produced as output a simple numerical vector or
    matrix it won't be visible here.<br><br>
    The single click is used to select, to have a look of the details of a single object in the Info panel on the right.<br>
    Double clicking on the list will add to the active LTPDA Simulink model (if any is selected) a "Object from list" block, so to
    import the object double-clicked in the given model.<br><br>

    <h2>Execution control panel</h2><hr><br>
    At the bottom of the window there are:
   	<ul>
	    <li>'<b><tt>Maintain intermediate results</tt></b>': enabling this ALL the outputs produced during the analysis (i.e., the
            output of every block) will be kept at the end of the analysis itself. This is meant as a way to verify intermediate
            results without the need to enable the 'Maintain' option for every single block, but of course should be used with
            care, since it will make the Input array very long and populated in a short time.<br>
	    <li>'<b><tt>Start button</tt></b>': this button starts the execution of the analysis. Till the end of the analysis it will
            turn to red. Although the common Simulink '<tt>Start simulation</tt>' button will correctly execute the model, the
            user should anytime use just the button enclosed in the GUI, which fulfills many extra purposes; for example, it will 
            update the Input array list in the main panel, removing all the intermediate results (whenever not differently set),
            it will open the progress bar window to represent the analysis proceeding, and it will add terminators in the model 
            wherever necessary.<br>
   	</ul>
    To make easier the start of the analysis, a direct copy of this button is shown in the upper right corner of the window,
    outside the first panel. This is visible from every panel, so it will be possible to start the execution without the need to
    open the main panel first.<br>
    
</p>