Math function

Perform mathematical functions.

Collaboration diagram for Math function:

Performs basic mathematical functions (exp, log, log10, root, sqrt, pow). The mathfunction object is defined through its parameters, which give the kind of mathfunction, the port widths and the number of input ports. An argument outside the domain of the function (log of a negative number, division by zero in root) gives inf or NaN, which the engine's NaN check stops.

Author

Benjamin Scholz

Date

05.09.2007 BSC: Second version.

20.07.2011 KGA: Ported to FhSim 2.0.

25.07.2011 KGA: Added documentation.

Example configuration excerpt

<Lib
  LibName     = "fhsim_base"
  SimObject   = "Math/Mathfunction"
  Name        = "Exp"
  MathType    = "exp"
  PortWidth   = "2"
/>
...
<Connection
  Exp.In = "1.1,0.9"
/>

Supported mathematical functions

Function	Input ports	Input name
Exponential	1	exp
Natural logarithm	1	log
Base 10 logarithm	1	log10
Square root	1	sqrt
Raise to power	2	pow
Root of number	2	root

Input Ports

Name	Width	Description
In	<PortWidth>	The input signal. This input is used for the following functions: exp, log, log10 and sqrt
In1	<PortWidth>	The base for pow and root. This input is used for the following functions: pow and root
In2	<PortWidth>	The the exponent or root value. This input is used for the following functions: pow and root

Output Ports

Name	Width	Description
Out	<PortWidth>	The result of the operations on the input

Configuration parameters

Name	Width	Description
PortWidth	-	The number of elements in the input and output ports
MathType	-	Specify the math function: exp / log / log10 / sqrt / pow / root

Initial conditions

There are no initial conditions for this function.

Full example file

<Contents>
  <OBJECTS>
    <Lib
        LibName="base"
        SimObject="Math/Mathfunction"
        Name="Exp"
        MathType="exp"
    />
 
    <Lib
         LibName="base"
         SimObject="Math/Mathfunction"
         Name="Log"
         MathType="log"
    />
    <Lib
          LibName="base"
          SimObject="Math/Mathfunction"
          Name="Log10"
          MathType="log10"
    />
    <Lib
        LibName="base"
        SimObject="Math/Mathfunction"
        Name="Sqrt"
        MathType="sqrt"
    />
    <Lib
        LibName="base"
        SimObject="Math/Mathfunction"
        Name="Pow"
        MathType="pow"
    />
    <Lib
        LibName="base"
        SimObject="Math/Mathfunction"
        Name="Root"
        MathType="root"
    />
  
  </OBJECTS>
  
  <INTERCONNECTIONS>
        <Connection
        Exp.In="1"
        Log.In="2.718281828459045"
        Log10.In="1000"
        Sqrt.In="49"
        Pow.In1="3"
        Pow.In2="2"
        Root.In1="8"
        Root.In2="3"
    />
  </INTERCONNECTIONS>
 
  <INITIALIZATION>
    <InitialCondition
    />
  </INITIALIZATION>
 
  <SIMULATION>
    <Timing TStart="0" TEnd="2.0"/>
    <Integrator Method="RK45_i" NumCores="1" LogStates="1" UseRSSNorm="0">
      <StepControl StepMax="0.002" StepMin="0.00000001" AbsTol="1e-3" RelTol="1e-3"/>
    </Integrator>
    
  </SIMULATION>
 
<OBSERVERS>
    <FileOutput TOutput="0, 1, 30" Select="objects:all"/>
  </OBSERVERS>
</Contents>

This SimObject is referred to as Math/Mathfunction