MATLAB SIMEVENTS RELEASE NOTES Guia do Utilizador descarregar pdf (Página 71)

Specify Intergeneration Times for Entities

3-5

Comparison of Approaches

Using intergeneration times from a distribution might be appropriate if you have a

mathematical model of the arrival process for the customers, packets, or other items that

entities represent in your model.

Using intergeneration times from a signal might be appropriate if you:

• Want to use a statistical distribution that is not constant, uniform, or exponential.

• Want the intergeneration time to depend on the dynamics of other blocks in your

model.

• Have a set of intergeneration times in a MATLAB workspace variable or in a MAT-

file.

How to Specify a Distribution

• “Specify a Constant, Uniform, or Exponential Distribution” on page 3-5

• “Specify Other Probability Distributions” on page 3-7

Specify a Constant, Uniform, or Exponential Distribution

If you want entity intergeneration times to be constant or to follow a uniform or

exponential distribution, configure the Time-Based Entity Generator as follows:

Set Generate entities with to Intergeneration time from dialog.

Choose a statistical distribution to describe the time interval between successive

entities. Set the Distribution parameter to one of these values:

• Constant. Then set the Period parameter to the constant intergeneration time.

• Uniform. Then set the Minimum and Maximum parameters to define the range

of possible intergeneration times. The distribution is uniform over this range.

• Exponential. Then set the Mean parameter to the mean of the exponential

distribution. In a simulation with a large number of entities, the average

intergeneration time is close to the Mean parameter value.

Probability density functions and entity generation times

The uniform distribution has probability density function

1 2 ... 66 67 68 69 70 71 72 73 74 75 76 ... 113 114

Sem comentários

MATLAB SIMEVENTS RELEASE NOTES Guia do Utilizador Página 71