private void makect(int nc, float[] c, int startc) {
        int j, nch;
        float delta, deltaj;

        ip[1] = nc;
        if (nc > 1) {
            nch = nc >> 1;
            delta = (float)(0.785398163397448278999490867136046290 / nch);
            c[startc] = (float)Math.cos(delta * nch);
            c[startc + nch] = (float)(0.5 * c[startc]);
            for (j = 1; j < nch; j++) {
                deltaj = delta * j;
                c[startc + j] =  (float)(0.5 * Math.cos(deltaj));
                c[startc + nc - j] = (float)(0.5 * Math.sin(deltaj));
            }
        }
    }