DAN includes a screen oriented text editor for creating and modifying
algorithms and short ASCII data files.  It can also be used for editing
or examining any ASCII file that is less than 30,000 characters in
length.

Text is shown on the screen and scrolls as you move through the
file.  The screen cursor shows the location within the text where
`actions' occur; e.g.  the point where characters will be inserted. 
Movement through the file is accomplished using the cursor control
keys, Home, End, and the Page Up and Page Down keys.

The editor displays a menu bar under the main DAN menu that shows the
editing functions it can perform.  These functions are selected by
typing the first letter of the action name; e.g. `F' to find a specified
pattern of characters within the text.  The editor will beep if an
unrecognized command is entered.  The menu bar is replaced by a help
line when insert or exchange modes are in effect.
+
The editor interprets characters entered from the keyboard as commands
until an `I',`X', or the `Ins' key is entered.  The `Insert' command
stops DAN from interpreting each character as a command and causes
subsequent characters to be inserted in the text at the current cursor
location.  The `Xchange' command also suppresses command
interpretation, but it causes subsequent typed characters to be
exchanged for the character under the cursor (i.e.  overtype).  Use the
`Ins' key to toggle between insert and exchange mode.

Function keys, such as `F4' to execute the algorithm, are recognized
during insert/exchange mode.  Use the `Esc' key to stop the
insert/exchange mode and return to the command entry mode.
+
                  TEXT EDITOR KEYS
                  ----------------
DAN's text editor recognizes the following keys:

CURSOR MOVEMENT KEYS
--------------------
cursor left, right     Move the active editing point left or right
                       by one character.

cursor up, down        Move the active editing point up or down one line.
                       If at the top or bottom of the screen then the
                       text will scroll appropriately by one line.

PgUp, PgDn             Move active editing point up or down by 21 lines;
                       i.e. by one page.

Home, End              Move to beginning or end of current line.

Ctrl-Home, Ctrl-End    Move to beginning or end of file.
+
EDITING FUNCTIONS
-----------------
Del         Delete the character at the current cursor location.

Backspace   Delete the character to the left of the cursor's location.

I, Ins      Enable insert mode.  Subsequent characters entered from the
            keyboard will be inserted in the text at the current cursor
            location.  Toggle between insert and exchange mode with the
            `Ins' key.  Insert mode is disabled with the `Esc' key.

X, Ins      Enable exchange mode.  Subsequent characters entered from
            the keyboard will overtype the text at the current cursor
            location.  Toggle between insert and exchange mode with the
            `Ins' key.  Exchange mode is disabled with the `Esc' key.
+
D           Delete a block of text from the current cursor location to
            a specified end point.  The end point is indicated by
            hitting the `D' key again after having moved the cursor to
            a position one character past the last character to be
            deleted.

            Use the `Esc' key to cancel a delete operation.

            Deleted text is saved in a paste buffer and may be
            re-inserted using the Paste function.  Use the Delete and
            Paste functions to move a block of text from one place to
            another.

C           Copy a block of text to the paste buffer.  This function is
            used, along with the Paste function, to duplicate text
            without deleting the original text block.  Cancel a copy
            operation with the `Esc' key.
+
P           Insert the contents of the paste buffer at the current
            cursor location.  Use in conjunction with Copy and Delete
            functions.

F           Find a pattern of characters in the text.  Cursor will be
            moved to the next place where the specified Find string
            is located (or a `Text not found' message will be output).
            Cancel without performing the Find operation, by using the
            `Esc' key.  Hit `F4' to perform the Find operation.  Use
            the Again function to find the next occurrence.

R           Replace one text string with another.  Previously entered
            text patterns are saved and may be edited using the cursor
            control keys, the Home and End keys, and the Del,
            Backspace, and Ins keys.  Cancel with the `Esc' key.   Use
            the Again function to repeat the Replace operation.
+
A           Repeat the last Find or Replace operation (i.e. whichever
            operation was performed last) using the parameters that
            were previously entered for the Find or Replace.

E           Display next error found during the last compilation of the
            algorithm.  Hit `E' to move to successive error locations.

K           Perform an error check on the current algorithm and show
            successive error messages (up to the first 10 errors).  The
            error message will appear above and to the right of the spot
            in the algorithm where DAN detected the error; that is, the
            lower left corner of the error message box is DAN's best
            guess at the location of the error.

H           Display help information for key words in the algorithm.
            Use the cursor keys to highlight the keyword or variable
            that you wish information on.  Hit `Enter' or `F1' to see
            the help information.  Use `Esc' to cancel Help mode.

Q, Esc      Exit the editor and return to DAN's top level menu.
+
FUNCTION KEYS
-------------
F1          Show help information for DAN's text editor.

F2          Save the current text file.  You are given the option to
            specify a new name for the file.  The current file name (if
            any) is the default name.  The default name may be edited
            in the same manner as the Find and Replace text patterns. 
            Hit `F4' when you have completed entering the file and path
            names.  If no path name is given then the current directory
            will be used.
+
F3          Reload/load a new text file.  You may specify a file and
            path name.  Hit `F4' to perform the load operation when the
            form shows the desired file and path names.

            Alternatively, you may enter a file name containing the DOS
            wildcard characters (`*' and `?'), or leave the file name
            blank (equivalent to entering `*.ALG').  If wildcards are
            used or the file name is blank, hit `F10' (not `Enter' or
            `F4') to see the possible choices that match the ambiguous
            file name.  Then use the cursor keys, `PgUp', `PgDn',
            `Home', or `End' to highlight one of the choices and hit
            `Enter' to load that file.
            
+
F4          Execute the current algorithm.  After execution is
            complete, control returns to the text editor.

F5          Clear the algorithm; i.e.  reset the algorithm buffer to
            blanks and delete the name.  You will be asked to verify
            your Clear request before the operation is executed.
            Enter `Y' (or `y') to proceed.  Any other character will
            cancel the Clear request.

F10         Show a list of DAN's keywords.  Help information on each
            keyword is available by using the cursor keys to move the
            highlight to any word on the screen and then hitting `F1'
            or `Enter'.

Shift-F2    Invoke any of DAN's forms, for example, to examine or
            modify the processing duration.
