T-FLEX Parametric CAD. Fundamentals. 2D Design

Fundamentals. Two-Dimensional Design
FUNCTIONS
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T-FLEX CAD supports construction lines defined by explicit mathematical formulation. Such construction
lines are called functions. To define a function, specify its definition type (parametric, plain, etc.), the start
and end of the parameter range, various display parameters of the curve.
You can work in two modes: either using a predefined formula from the provided set, or creating a new
function. The set of predefined functions is stored in the file “function.dat”. The file name is defined in the
item “Function spline file” of the command “SO: Set System Options” (“Customize|Options|Files”).
The file “function.dat” can be edited or replaced, if desired. Notations for the parameters, accepted in the file,
are as follows: #1 – first parameter, #2 - second parameter of the function (can be optional). Follows is a
detailed description of these parameters.
The system treats the resulting construction line of the function as a spline, therefore, the key is used for
its selection in various commands.
Defining the Function
The entities defined by a function are input via the command “FU: Construct Function Spline”
Keyboard Textual Menu Icon
“Construct|Function Spline”
The following options are available to the user:
, Free mode on/off toggle
Select nearest node or create node defining the function
coordinate system
Select Node (for defining the function coordinate system).
Set entity parameters
Select symmetry axis (Line) (for constructing a
symmetrical function spline)
Execute Edit Construction command
Exit command
The function spline construction entity allows defining construction entities of virtually any kind. The main
condition is possibility of defining construction entities in a form of functional relation between the
coordinates.
The system provides an option of selecting predefined functions defining various curves, such as parabola,
evolvent, spiral, etc. You can also define your functions independently, and then use them. For this purpose,
create a descriptor file or append an already existing one with new formulas and values of other parameters
defined in the function parameters dialog box.