Date: Wed, 24 Sep 2003 12:08:00 -0400 (EDT)

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You may have noticed that the MOI code we prepared for the class to
use only exposes the three moments of inertia through the MOI class
interface.  Hecker's code describes how to use the entire inertia
tensor (including the six products of inertia that are off-diagonal on
the inertia matrix).  Getting at the entire inertia matrix should be
easy enough, but I've included a method for moi.cpp to do that for
you:

void MOI::GetMOImatrix (double x[9]) {
  int i, j;
  for (i=0; i<3; i++) {
    for (j=0; j<3; j++) {
      x[i*3+j] = moi[i][j];
    }
  }
}

We also found what was a small bug that interfered with generating the
products of inertia (failure to initialize a matrix to 0.0) so please 
replace your JDMatrix constructor in JDMatrix.cpp with the following:

JDMatrix::JDMatrix(int rs,int cs){
    int i,j;
    rows = rs;
    columns = cs;
    data = new double*[rows];
    for(i = 0; i < rows; i++){
        data[i] = new double[columns];
    }
    for(i = 0; i < rows; i++){
        for(j = 0; j < columns; j++)
            data[i][j] = 0.0;
    }
}