2.2 Function editor


  The funktioneditor is a window, in which alle present  functions are
listed and can be edited.

  A function from the list-gadget appears in the string-gadget at the top
of the window by clicking the function. If finish the entered or modified
string with pressing <return>, the functionterm gets automatically
interpreted.

  If the interpreter detects an error in the function, the error gets
displayed in the "error" gadget below, and the "bad" function will appear
in italics in the function-list. Of course such a bad function cannot be
plotted or analyzed!

  Pressing the HELP-key over the function or error gadget shows immediately
the "Functions"-chapter of the documentation where you can find information
about the function-syntax.

  In the string-gadget "Graph" with the popup-list all existing graphs are
shown by their names. You can give an individual name to every graph. When
you double-click a graph in the list it will appear in the foreground.

  For a selected function you can define, whether and in which color and
pattern it should be visible in the selected graph. A double-click to a
function toggles the visible-mark as if you had clicked onto the
visible-gadget. A function that appears in the selected graph ist marked
with a preceding ">" in the function-list.

  Changes been made on a visible function will then be executed when you
click "Redraw" in the graph-window - not before! This allows you to do more
than one change at once without a time-consuming redraw after every
change.

As long as the function-editor is active, the following menus can be
selected:


Project

  New Graph...        - Creates a new graph-window. The graph type 
                        ( 2D-graph or  SIRDS-graph) has to be specified
                        in a little requester.
  Help...             - Opens the context-sensitive online-help like
                        pressing the HELP-key
  About...            - Opens an info-window
  Quit                - Quit Graph2D


Functions

  Clear all           - The functionlist will be deleted
  Load ...            - Load a functionlist
  Append...           - Append a functionlist (without deleting the
                        actual one)
  Save as...          - Save the functionliste


Edit

  New                 - A new, "empty" function will be added to the
                        list at the selected position and can be
                        immediately edited
  Cut                 - The selected function will be cut out of the list
  Paste               - A former cut-out function will be added to the
                        list at the selected position


Discussion

  Complete            -  Discussion
  Zero-points         -  Zero-points
  Extrema             -  Extrema
  Turning-points"     -  Turning-points
  Monotony            -  Monotony
  Symmetry            -  Symmetry


Miscellanious

  Simplify            - A simplified aequivalent of the selected function
                        will be added to the list
  Derive              - The derivation of the selected function will be
                        added to the list
  num. integration... - Allows you to calculate the integral of the
                        selected function in an intervall you have to
                        specify via the "Simpson"-formula
  Value-table...      - A value-table of the selected function in a
                        definable intervall and with a selectable step-
                        width will be generated
  Tangente ...        - A new function will be added to the list which
                        represents a tangete on a definable point of the
                        selected function
  math. notation...   - Opens the  notation-window with the
                        selected function