code: def test_matrix_params_build():
      """Sample from a program with matrix-valued params."""
      program_code = """
          data {
            int<lower=2> K;
            int<lower=1> D;
          }
          parameters {
            matrix[K,D] beta;
          }
          model {
            for (k in 1:K)
              for (d in 1:D)
                  beta[k,d] ~ normal(0, 1);
          }
      """
      data = {"K": 9, "D": 5}
      posterior = stan.build(program_code, data=data)
      assert posterior is not None
  
imports: import stan
label_desc: Use image node_id 2 for calling a global function with example usage: test_matrix_params_build() without return types