File: deriv.c

package info (click to toggle)
scilab 4.0-12
  • links: PTS
  • area: non-free
  • in suites: etch, etch-m68k
  • size: 100,640 kB
  • ctags: 57,333
  • sloc: ansic: 377,889; fortran: 242,862; xml: 179,819; tcl: 42,062; sh: 10,593; ml: 9,441; makefile: 4,377; cpp: 1,354; java: 621; csh: 260; yacc: 247; perl: 130; lex: 126; asm: 72; lisp: 30
file content (49 lines) | stat: -rw-r--r-- 981 bytes parent folder | download | duplicates (2) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
 

#include "scicos_block.h"
#include <math.h>

#if WIN32
#define NULL    0
#endif

void deriv(scicos_block *block,int flag)
{ 
  double* rw;
  double t,dt;
  int i;
  if (flag == 4){/* the workspace is used to store previous values */
    if ((*block->work=
	 scicos_malloc(sizeof(double)*2*(1+block->insz[0])))== NULL ) {
      set_block_error(-16);
      return;
    }
    rw=*block->work; 
    t=get_scicos_time();
    rw[0]=t;
    rw[1]=t;
    for(i=0;i<block->insz[0];++i){
      rw[2+2*i]=0;
      rw[3+2*i]=0;
    }
  }else  if (flag == 5){
    scicos_free(*block->work);
  }else  if (flag == 1) {
    rw=*block->work;
    t=get_scicos_time();
    if(t>rw[1]) {
      rw[0]=rw[1];
      for(i=0;i<block->insz[0];++i)  {rw[2+2*i]=rw[3+2*i];}
    }
    rw[1]=t;
    for(i=0;i<block->insz[0];++i) {
      rw[3+2*i]=block->inptr[0][i];
    }
    dt=rw[1]-rw[0];

    if(dt!=0.0) {
      for(i=0;i<block->insz[0];++i)
	block->outptr[0][i]=(rw[3+2*i]-rw[2+2*i])/dt;
    }
  }
}