9 const double L1 = x[0];
10 const double L2 = x[1];
11 const double t = x[2];
12 N[0] = 0.5 * (1.0 - L1 - L2) * (1.0 - t);
13 N[1] = 0.5 * L1 * (1.0 - t);
14 N[2] = 0.5 * L2 * (1.0 - t);
15 N[3] = 0.5 * (1.0 - L1 - L2) * (1.0 + t);
16 N[4] = 0.5 * L1 * (1.0 + t);
17 N[5] = 0.5 * L2 * (1.0 + t);