SFUN
----


.. figure:: ../media/image986.png
   :figwidth: 4.66667in
   :align: center 

**Purpose**

To transform an input signal . The transformation function can be either a sine-, polynome-, exponential- or power-function.

**Procedure** 

One of the following functions is used to transform the input signal :

=========== ======================================================
Sine        .. math:: y = A \cdot \sin\left( \text{Bx} - C \right)
Polynome    .. math:: y = A + \left( B + Cx \right)x
Exponential .. math:: y = Ae^{\text{Bx} - C}
Power       .. math:: y = sign(Ax + B) \times abs(Ax + B)^{C}
=========== ======================================================

**Parameters** 

========= ========= ==== ===== ======= =======
Parameter input     unit range default remarks
========= ========= ==== ===== ======= =======
Function  Sine/                        
          Polynome/                    
          exp/                         
          power                        
A         real                         
B         real                         
C         real                         
========= ========= ==== ===== ======= =======

**Remarks** 

The SFUN component is different from the FUN component, because the time itself is not used within the function. It will be obvious that if the input *x* is time-dependent, the output varies in time also.

**Examples** 

.. figure:: ../media/image987.png
   :figwidth: 3.625in
   :align: center 

   Control Scheme

Figures 2a – 2d present output of different type of functions, where the input signal does vary with time (increasing from 0 – 10, see fig 1) and hence the output signals are also time-dependent.

+----------------------------------------+-------------------------------------------+
| |image236|                             | |image237|                                |
+----------------------------------------+-------------------------------------------+
| Figure 2a:Sine signal (A= 2, B=1, C=2) | Figure 2b:Sine signal (A= 50, B=-10, C=2) |
+----------------------------------------+-------------------------------------------+

+-----------------------------------------------+--------------------------------------------+
| |image240|                                    | |image241|                                 |
+-----------------------------------------------+--------------------------------------------+
| Figure 2c:Exponential signal (A= 2, B=1, C=2) | Figure 2d:Poweer signal (A= -20, B=1, C=2) |
+-----------------------------------------------+--------------------------------------------+

.. include:: substitutions_control.rst