Interpolation
Keywords: main

Subsections

- Library
- Description
- Dialog Box
- Default properties
- Interfacing function
- Computational function (type 0)

##
Interpolation

### Library

Non_linear

### Description

The output of this block is a function of the input obtained by linear interpolation. This block has a single scalar input and a single scalar output port. The coord. and coord. give respectively the coordinate and the coordinate of the data points to be interpolated. coord must be strictly increasing.

### Dialog Box

Set Interpolation block parameters |
X coord. | [0;1]
Y coord. | [0;1]

- X coord.:A vector (strictly increasing).
- Y coord.:A vector (same size as coord).

### 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: intrpl

### Interfacing function

`scilab/macros/scicos_blocks/nonlinear/INTRPLBLK_f.sci`

### Computational function (type 0)

          subroutine intrpl(flag,nevprt,t,xd,x,nx,z,nz,tvec,ntvec,
         &     rpar,nrpar,ipar,nipar,u1,nu1,y1,ny1)
    c     Copyright INRIA

    c     Scicos block simulator
    c     ipar(1) : the number of input
    c
          double precision t,xd(*),x(*),z(*),tvec(*),rpar(*)
          double precision y1,u1
          integer flag,nevprt,nx,nz,ntvec,nrpar,ipar(*),i
          integer nipar
    c
    c
          do 100 i=2,nrpar/2
             if (u1.le.rpar(i)) goto 200
     100  continue
          i=nrpar/2
     200  continue
          y1=rpar(nrpar/2+i-1) + ((rpar(nrpar/2+i)-rpar(nrpar/2+i-1))/
         $     (rpar(i)-rpar(i-1)))*(u1-rpar(i-1))
          return
          end