用opencv嵌套yaml

Question

我正在使用OpenCV编写带有嵌套列表的yaml文件。输出看起来很奇怪，但也许是正确的

void nested_yaml() {
    cv::FileStorage write_fs;
    write_fs.open("../trajectory.yml", cv::FileStorage::WRITE);

    for ( unsigned i = 1; i < 3 ; i++ ) {

        char temp_str_fs[20];
        sprintf(temp_str_fs, "i_%03d", i);
        write_fs << temp_str_fs << "[";

        for (ushort j = 0; j < 4; j++) {
            char temp_str_fc[20];
            sprintf(temp_str_fc, "j_%03d", j);
            write_fs << temp_str_fc << "[";
            write_fs << "{:" << "name" << "hello" << "x" << 1 << "y" << 2 << "}";
            write_fs << "]";
        }
        write_fs << "]";
    }
    write_fs.release();
}

第一个问题是输出是否正确？

第二个问题是如何使用cv :: FileNode回读j_00x下的元素。

yaml文件的输出

%YAML:1.0
---
i_001:
   - j_000
   -
      - { name:hello, x:1, y:2 }
   - j_001
   -
      - { name:hello, x:1, y:2 }
   - j_002
   -
      - { name:hello, x:1, y:2 }
   - j_003
   -
      - { name:hello, x:1, y:2 }
i_002:
   - j_000
   -
      - { name:hello, x:1, y:2 }
   - j_001
   -
      - { name:hello, x:1, y:2 }
   - j_002
   -
      - { name:hello, x:1, y:2 }
   - j_003
   -
      - { name:hello, x:1, y:2 }