code: public void setRandomStandardNormal() {
          FnIntDoubleToDouble lambda = new FnIntDoubleToDouble() {
              @Override
              public double call(int idx, double val) {
                  return Gaussian.nextDouble(0.0, 1.0);
              }
          };
          apply(lambda);
      }
docs: Fill the model parameters with values randomly drawn from ~ Normal(0, 1).