Class: HilbertMatrix

Inherits:
Object
  • Object
show all
Defined in:
ext/hilbert/hilbert.c

Instance Method Summary collapse

Instance Method Details

#execute(a, b, n) ⇒ Object 



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# File 'ext/hilbert/hilbert.c', line 19

static VALUE
execute(VALUE self, VALUE a, VALUE b, VALUE n)
{
  GET_FLOAT(a);
  GET_FLOAT(b);
  GET_FLOAT(n);

  int i;
  double s1=0.0, s2=0.0, d;
  double x, y[n+1];
  d=(b-a)/(double)n;
  for(i=0; i<=n; i++)
  {
    x=(double)i*d+a;
    y[i]=func(x);
  }
  for(i=1; i<=n-1; i+=2)
  {
    s1+=y[i];
  }
  for(i=2; i<=n-2; i+=2)
  {
    s2+=y[i];
  }

  double s=(y[0]+4.0*s1+2.0*s2+y[n])*d/3.0;

  return DBL2NUM(s);
}

#func(x) ⇒ Object 



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# File 'ext/hilbert/hilbert.c', line 11

static VALUE
rb_func(VALUE self, VALUE x)
{
  GET_FLOAT(x);
  return(DBL2NUM((x * x)/2));
}