Quantization

Library

Non_linear

Description

This block outputs the quantization of the input according to a choice of methods:

1. Round method:

   $$y(i) =Step*(int(u(i)/Step+0.5)-0.5) \texttt{if} u(i)<0 .$$

   $$y(i) =Step*(int(u(i)/Step-0.5)+0.5) \texttt{if} u(i)>=0 .$$

   
   

2. Truncation method:

   $$y(i) =Step*(int(u(i)/Step+0.5)) \texttt{if} u(i)<0 .$$

   $$y(i) =Step*(int(u(i)/Step-0.5)) \texttt{if} u(i)>=0 .$$

   
   

3. Floor method:

   $$y(i) =Step*(int(u(i)/Step+0.5)) .$$

   
   

4. Ceil method:

   $$y(i) =Step*(int(u(i)/Step-0.5))$$

   
   

Dialog Box

Set parameters
Step	0.1
Quantization Type (1-4)	1

• Step:scalar, Quantization step
• Quantization Type : scalar with possible values 1,2,3 or 4

  1

  Round method

  2

  Truncation method

  3

  Floor method

  4

  Ceil method

Default properties

• always active: no
• direct-feedthrough: yes
• zero-crossing: no
• mode: no
• number/sizes of inputs: 1 / -1
• number/sizes of outputs: 1 / -1
• number/sizes of activation inputs: 0 /
• number/sizes of activation outputs: 0 /
• continuous-time state: no
• discrete-time state: no
• name of computational function: qzrnd

Interfacing function

scilab/macros/scicos_blocks/nonlinear/QUANT_f.sci

Computational function (type 0)

      subroutine qzrnd(flag,nevprt,t,xd,x,nx,z,nz,tvec,ntvec,
     &     rpar,nrpar,ipar,nipar,u,nu,y,ny)
c     Copyright INRIA

c     Scicos block simulator
c
c     Gives quantized signal by round method
c     rpar(i) quantization step used for i input
c
      double precision t,xd(*),x(*),z(*),tvec(*),rpar(*),u(*),y(*)
      integer flag,nevprt,nx,nz,ntvec,nrpar,ipar(*)
      integer nipar,nu,ny


      integer i
c
      do 15 i=1,nu
         if (u(i).lt.0.0d0)then
            y(i)=rpar(i)*(ANINT(u(i)/rpar(i)+0.5d0)-0.5d0)
         else
            y(i)=rpar(i)*(ANINT(u(i)/rpar(i)-0.5d0)+0.5d0)
         endif
 15   continue
      return
      end