2.1 Design Logic Creation

The first project tool to be used is the Work Flow (Fig. T2.1.1).

Fig. T2.1.1: the Work Flow window.

This can be activated by clicking on the corresponding tab, or selecting Project|Work Flow from the menu.

The window is divided into three parts:

• the top part (the proper Work Flow graphical panel, marked in a cyan box): it is the desktop where the logic is created.
• the bottom part (Logic Log/Summary, marked in a yellow box): click on one of the tabs to toggle between their respective panels.
  The Logic Log panel shows a list of warning/error messages detected by the just-in-time logic compiler. Only if there are no errors a project is ready to be run.
  The Summary panel shows a brief summary of the project, about its components and their relevant properties; thus it's possible to keep the entire process logic under control with just a glance. Some tables are editable for quick modification.
• The left part (a tool bar marked in a magenta box): it includes all the components needed to create data & logic flow.
  (Note: above the Work Flow there is another tool bar, here not marked, which use is more specific and is not handled in this tutorial.)

When you start a new project, the Logic Log shows an error message (as you can see in Fig. T2.1.1): Error150 MISSING SCHEDULER NODE. This is perfectly normal, since the project is empty: we miss not only the scheduler node, but also all the others necessary nodes that have to be implemented in a correct project definition.
Proceeding in the construction of the project, other errors will appear, marking the various phases of our work in progress.

Many components are needed in order to construct properly a project: but the order in which these components are defined is more a question of user's style or logic.
Two main flows can be found in any project: a data flow - that is the line going from input data to output data - and a logic flow - that is the line going from the start to the end of the execution process-. As we will see, these two flows intersect in the External Script node (see section 2.4).
In this tutorial we will define first the data flow, since it is simpler for a new user to follow the path going from input variables to output variables.
These input/output variables can however be completed, modified, created or removed at any time during the logic creation process, as can be done with every other component.

Note: from now on, an "RMB click" will indicate a click with the right mouse button, while an "LMB click" or simply "click" will indicate a click with the left mouse button.

To place a component on the Work Flow desktop, select it by clicking on the left tool bar, then click on the desktop; to place many copies of the same selected component, click on the desktop as many times as the number of objects needed, while pressing the <CTRL> key.
Once a component is created, you can select it with a click, access its properties by a double click. With a RMB click a menu will pop-up menu, where you can select some actions to perform on the component:

• Remove Node to remove the selected object from the logic flow.
• Remove Links to remove all links from the selected object to any other node previously linked to.
• Edit Graphic Properties to edit the object graphic properties.
• Edit Node Properties to access the object properties (equivalent to a double click).

If a component is selected and you want to leave the "component insertion mode", click on the neutral icon on top of the Work Flow tool bar.

Let's start creating 9 input variables and 5 output variables : since there are many input variables, it is better to use the multiple input variables icon , which can be accessed by clicking the little bottom-right black corner of the input variable icon. Selecting the icons from the palette on the left and placing the items on the Work Flow area we obtain Fig. T2.1.2:

Fig. T2.1.2: the Work Flow desktop with all variables placed.

The Logic Log panel is now populated with a list of Error 113 OUTPUT LINK(S) and Error 112 MISSING OUTPUT LINK(S): again you do not have to worry about them, since they will be progressively fixed, as the project goes on. The presence of an error in a component is also signaled by the red border of the incriminated object.

Now give the correct names to input and output variables: to do this, enter the variable properties dialog, by double clicking on each variable object (see Fig. T2.1.3 and Fig. T2.1.4).

Fig. T2.1.3: Input variable properties window. Variable type: constant.

Fig. T2.1.4: Input variable properties window. Variable type: variable.

Variables names and properties can also be modified using the Summary panel.

In this example the Young module, S, F, Mc and Wc are kept constant. This is done by setting the variable type as constant, in the relevant combo box (see Fig. T2.1.3); in this way the variable is kept constant and is not considered by the optimisation algorithms.
In the case of a proper variable type (see Fig. T2.1.4), the base and step parameters determine if a variable is continue or if it is discrete. The base parameter gives the number of subdivisions for each variable; alternatively the step parameter gives the increment to be adopted. A base or a step equal to 0 means that the variable is continue.
In our case the beam thickness B can vary from 1 to 15 mm but on finite steps of 1 mm so the variable B will have:

        B lower bound = 1
        B upper bound = 15
        B base = 15
        B step = 1
    

Fig. T2.1.5: the Summary Table for input and output variables.

Fig. T2.1.6: the Work Flow window.