T-FLEX Parametric CAD. Fundamentals. 2D Design

Functions
The definition procedure includes two stages:
1. Defining the coordinate system position (X and Y). The coordinate system helps defining the desired
position of the resulting entity on the drawing. The coordinate system is defined by sequential selection
of two nodes. The first node defines the origin (0,0). The second node defines the direction of the X-axis.
The Y-axis is defined automatically based on the origin and the X-axis positions.
2. Defining the functional relation and other parameters. This is done in the function parameters dialog
box that appears on the screen after selecting the second node.
The following parameters are defined in the function
parameters dialog box:
Name of the formula. One can select from the list a
name of a standard function or define an arbitrary name
for creating a new function.
Type, or the way of defining the function. Four different
types of definition can be used:
− Plain definition in Cartesian coordinates (Y = f
(X))
Example: Y= #1**2 defines a parabola.
The notation #1 is used for the variable parameter (in
this case - X). This special notation is used to avoid
confusion with the system variable names that can be
used in the expression defining the functional
relation.
Besides variables, functions can be used as well as
they are supported for use in the variable editor.
− Parametric definition in the Cartesian coordinate
(X = f(t), Y = f (t)).
Example: X = #1, Y = #1 defines a straight line.
One can create, for instance, a database of cam coordinates, and then use a
parametric definition for the cam contour. Use the database access
functionality and define a parametric relation where the variable parameter
#1 is the record number in this database. The specified number of steps must
necessarily equate with the difference between the end and start values of
the function variable parameter.
The indicator of the end value, or the end record, in the database named “q” can be conveniently
entered as the expression “q.#”, returning the number of the last record in the database q.
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