/****************************************************************
*  datamov.c - This function updates signal vector for FIR filter
****************************************************************/
void  datamov(x, L, input)

float *x;             // signal vector
int L;                // length of vector
float input;          // newest input sample
{
  int i;              // loop index
  for (i=L-1; i>0; --i)
  {
    x[i] = x[i-1];    // shift old data x(n-i), i = 1, 2, ... L-1
  }                   // such as x(0) -> x(1), etc.
  x[0] = input;       // insert new data x(n) into x(0)
}