Using Input Lines and Keyboard

Home > 01 Getting Started > Using Input Lines and Keyboard

The input line at the bottom of the screen is the area used for interaction between the program and the user. Most commands require you to input information. As required, an appropriate prompt message or instruction is displayed on the input line. The input line actually comprises two rows — one for messages from the system and one for user input.

The upper row displays system messages and prompts .

The bottom row for entering command names and options, coordinate values and other parameters via the keyboard.

NOTE When you enter the commands in the input lines, they should always be preceded by backslash (\) or a slash (/).

Prompts on the input line

The prompts are the system messages that guide you through the selections and possible options of a given command. The first part of the prompt (within brackets) defines the general category of the required input where as the second defines the type of the specific information required. In the following example,

(POINT) first corner of fence

The prompt tells you to specify a point (either with the mouse or by coordinate values), which will define the corner of the fence, for a particular command.

The general types of parameters are as follows:

Prompt	Explication
(point)	Pick a point. The value of the point must be defined on x, y and z
(ind)	Indicate an entity in the model
(num)	Enter a number or value
(char)	Enter characters, for example, the letter representing an option
(y/n)	Answer yes or no

Another aspect of using the input line is that you don't have to wait for the prompts. In most cases, if you know the order of the prompts, you can type the answers in sequence before they are displayed. For example, \walk l 90 has two parameters–l = left and 90 = ninety degrees. (The only exceptions to this are prompts requesting ind–to indicate an entity, and those requesting to press Enter to continue).

As you become more experienced with the system you can enter a string of parameters in sequence (with spaces between them), e.g., in response to a series of prompts in a given command, or even a string of commands and parameters.

When typing in the input line, you can use the regular text editing keys of your keyboard such as Ins, Del, Backspace, End Home and arrows. Shift pressed simultaneously with End or Home deletes the line from the cursor to the end or beginning of the line respectively.

Default

In certain commands, the system displays a suggested parameter, known as a, default. The default values are either frequently used parameters preset by the system or parameters that you have specified previously (during the current work session). You can accept the default simply by pressing Enter or enter a different parameter by overwriting it. To clear the default press the Spacebar.

Error Messages

The system verifies the user inputs and rejects illegal inputs. An error message is displayed when you enter an illegal parameter. The parameter and the prompt remain on the input line to enable you to correct your inputs. In some cases the message describes the error type.

Using Keyboard Shortcuts

In addition to the pull-down menu and the input line, you can enter ARC+ commands via shortcut keys. The shortcut keys are combinations of control and other keys used to operate commands. The keys for commands that possess a shortcut code are listed in brackets [ ] in the command descriptions, e.g., [Ctrl+O] which operates the command to open a file.

Various keyboard keys have been programmed for special functions in ARC+.

These keys and their functions are listed in the description of every command and summarized in a table in Appendix C.

NOTE Some commands are available via the keyboard or menus only.

Displaying the History of your Previous Commands

ARC+ stores a history of the commands that you run and can display them again (also their options and parameters) on the input line. A list of commands stored in the history is displayed by the up and down arrows of your keyboard (not on the numeric keypad).

When the desired command is displayed on the input line, press Enter to execute it again.

Or you may edit the displayed command parameters and then press Enter to execute the edited command line. (Parameters typed in the input line as a string along with the command name are also displayed.)

To customize your keyboard, see Customize your ARC+ environment.