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Configuring the Attributes of Blocks

 Once you have cloned and connected blocks on a workspace, the next step in creating a diagram is to configure the attributes of each block.

Most blocks contain a number of attributes that you can configure to specify the particular behavior of the block. All attributes have default values so that, by default, most blocks can evaluate without being configured. However, you typically will want to configure all blocks as part of creating a diagram. Some simple blocks do not have any configurable attributes.

The two ways of configuring the attributes of blocks are:

Configuring Attributes in the Configuration Panel

 You use the block's configuration panel to configure its attributes.

To configure the attributes of a block through its configuration panel:

  1. Select configure from the block's menu.

    If a block does not have any configurable attributes, configure does not appear as a menu choice for the block.

  2. Enter the attribute values via a configuration panel.

Note: You cannot use a block's table for entering attribute values into the block, even in Administrator mode.
The following figure illustrates the configuration panel for a High Value observation block with the attribute types labeled:


To enter a value in an edit box:

  1. Select the box with the mouse.

    This changes the background color of the edit box indicating it is active.

  2. Delete the current value, for example, using Ctrl-x to delete backwards.

  3. Enter a new value in the edit box.

  4. Press the Return key.

    This changes the background color of the edit box to its original color.

If the value you entered is not of the correct type, NOL displays an error message when you press the Return key. NOL also validates dependencies between attributes of the block when you enter values. For example, for blocks that specify upper and lower thresholds, NOL verifies that the upper threshold is greater than the lower threshold.

When you enter text strings in a configuration panel, you do not need to enter quote marks; NOL handles this internally for you. The only time you need to enter quote marks in a configuration panel is when entering an expression, as described in "Evaluating Expressions in Attributes".

Some blocks allow you to edit attribute values via attribute displays, for example, the Threshold attribute for the High Value observation block. Note that NOL does not perform validation on values entered via attribute displays.

To select a new value by using a radio button:

To display a child dialog:

The configuration panel includes the following buttons:

This button... Performs this action...
OK
Accepts new values and closes the configuration panel
Apply
Accepts new values and leaves the configuration panel open
Cancel
Discards new values and closes the configuration panel

Editing Attribute Displays

Some blocks display attribute values with the icon, which you can edit directly. For example, many observation blocks display the Threshold attribute with the icon. To edit the attribute, simply click on the attribute display and enter a new value.

To configure the attribute of a block by editing its attribute display:

Here is a High Value observation block whose Threshold attribute display is being edited:


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