Mechanical APDL Basic Analysis Guide

• Function Loader -- Retrieves the functions and loads them as table arrays.

The following terms apply when using the Function Tool:

• Function -- A set of equations that together define an advanced boundary condition.


• Primary Variable -- An independent variable evaluated and used by the program during solution.


• Regime -- A portion of an operating range or design space characterized by a single regime variable.
  Regimes are partitioned according to lower and upper bounds of the regime variable. The regime
  variable must be continuous across the entire regime. Each regime contains a unique equation to
  evaluate the function.


• Regime Variable -- The defining variable that governs which of the set of equations is used to evaluate
  the function.


• Equation Variable -- A dependent (user-specified) variable, defined when the function is loaded.

3.2. Using the Function Editor

The Function Editor defines an equation or a function (a series of equations). You use a set of primary
variables, equation variables, and mathematical functions to build the equations. Each equation applies
to a particular regime. The equations defined for each regime, taken together, define a function, and
the function as a whole is applied (for example, as a boundary condition, or to define the nonlinear
material behavior for a joint).

The following topics related to the Function Editor component of the Function Tool are available:

3.2.1. How the Function Editor Works

3.2.2. Creating a Function with the Function Editor

3.2.3. Using Your Function

3.2.1. How the Function Editor Works

Using the Function Editor is similar to using a scientific calculator. For example, when building an
equation, you can:

• Click buttons on the on-screen keypad.

The keypad includes the numbers 0-9, parentheses, and a set of mathematical operators. In ad-

dition to the default set of operators, you can also click the INV key to access an alternate set

of operators.

• Use any variable name.

The editor interprets any variable name you type as an equation variable. You can use up to 10

user-defined equation variables in a function (up to six regimes). You can use any name you

wish, but ANSYS, Inc. recommends against using the same name as one of the primary variables.

You define the values for these variables when you load the function (described in Using the

Function Loader (p. 83)).

• Select a primary variable from a drop-down list.

As you build an equation, it appears in standard mathematical syntax in the equation box above the
keypad. The various components (primary variables, equation variables, mathematical operators, and

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Using the Function Tool