Dataframe 将HDF5作为Dask数据帧读取时出错，原因是什么？

1。我的问题

我在尝试使用Dask读取HDF5文件时遇到下一个错误，我不知道为什么

>>> dd.read_hdf("test.h5", key="/RECORDS/STATES")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.7/site-packages/dask/dataframe/io/hdf.py", line 514, in read_hdf
    for path in paths
  File "/usr/local/lib/python3.7/site-packages/dask/dataframe/io/hdf.py", line 514, in <listcomp>
    for path in paths
  File "/usr/local/lib/python3.7/site-packages/dask/dataframe/io/hdf.py", line 382, in _read_single_hdf
    for k, s, d in zip(keys, stops, divisions)
  File "/usr/local/lib/python3.7/site-packages/dask/dataframe/multi.py", line 1071, in concat
    raise ValueError("No objects to concatenate")
ValueError: No objects to concatenate

其中，我基本上有3个数据集/记录（状态、事件和通信）。我觉得我的HDF5没有什么奇怪的地方。 我试着用Pandas和Dask数组加载这些数据集，效果很好

3。我想知道的

我的HDF5文件有什么问题，使Dask无法将其作为数据帧读取

---

我试图在Dask文档中找到HDF5文件必须满足的要求，但没有任何内容涉及此主题。如果至少我知道我的文件有什么问题，我就能解决它。

PR最近被合并到dask master中，幸运的是，它为您解决了这个问题。

事实上，这种合并解决了问题。非常感谢！：）

HDF5 "rhoPimpleExtrae10TimeSteps.00.1iter.h5" {
GROUP "/" {
   ATTRIBUTE "hdf5_metadata_apps" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SCALAR
   }
   ATTRIBUTE "hdf5_metadata_date" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SCALAR
   }
   ATTRIBUTE "hdf5_metadata_hwcpu" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SIMPLE { ( 48 ) / ( 48 ) }
   }
   ATTRIBUTE "hdf5_metadata_hwnodes" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
   }
   ATTRIBUTE "hdf5_metadata_name" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SCALAR
   }
   ATTRIBUTE "hdf5_metadata_nodes" {
      DATATYPE  H5T_STD_I64LE
      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
   }
   ATTRIBUTE "hdf5_metadata_path" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SCALAR
   }
   ATTRIBUTE "hdf5_metadata_threads" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SIMPLE { ( 48 ) / ( 48 ) }
   }
   ATTRIBUTE "hdf5_metadata_time" {
      DATATYPE  H5T_STD_I64LE
      DATASPACE  SCALAR
   }
   ATTRIBUTE "hdf5_metadata_type" {
      DATATYPE  H5T_STRING {
         STRSIZE H5T_VARIABLE;
         STRPAD H5T_STR_NULLTERM;
         CSET H5T_CSET_UTF8;
         CTYPE H5T_C_S1;
      }
      DATASPACE  SCALAR
   }
   GROUP "RECORDS" {
      DATASET "COMMUNICATIONS" {
         DATATYPE  H5T_COMPOUND {
            H5T_STD_U32LE "CPU Send ID";
            H5T_STD_U32LE "Phy. Task Send ID";
            H5T_STD_U32LE "Log. Task Send ID";
            H5T_STD_U32LE "Thread Send ID";
            H5T_STD_U64LE "Log. Send Time";
            H5T_STD_U64LE "Phy. Send Time";
            H5T_STD_U32LE "CPU Receive ID";
            H5T_STD_U32LE "Phy. Task Receive ID";
            H5T_STD_U32LE "Log. Task Receive ID";
            H5T_STD_U32LE "Thread Receive ID";
            H5T_STD_U64LE "Log. Receive Time";
            H5T_STD_U64LE "Phy. Receive Time";
            H5T_STD_U64LE "Size";
            H5T_STD_U64LE "Tag";
         }
         DATASPACE  SIMPLE { ( 67574 ) / ( H5S_UNLIMITED ) }
         ATTRIBUTE "CLASS" {
            DATATYPE  H5T_STRING {
               STRSIZE 6;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_0_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 12;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_10_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 18;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_11_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 18;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_12_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 5;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_13_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 4;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_1_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 18;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_2_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 18;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_3_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 15;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_4_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 15;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_5_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 15;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_6_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 15;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_7_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 21;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_8_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 21;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_9_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 18;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "TITLE" {
            DATATYPE  H5T_STRING {
               STRSIZE 22;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "VERSION" {
            DATATYPE  H5T_STRING {
               STRSIZE 4;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
      }
      DATASET "EVENTS" {
         DATATYPE  H5T_COMPOUND {
            H5T_STD_U32LE "CPU ID";
            H5T_STD_U16LE "APP ID";
            H5T_STD_U32LE "Task ID";
            H5T_STD_U32LE "Thread ID";
            H5T_STD_U64LE "Time";
            H5T_STD_U64LE "Event Type";
            H5T_STD_U64LE "Event Value";
         }
         DATASPACE  SIMPLE { ( 3643006 ) / ( H5S_UNLIMITED ) }
         ATTRIBUTE "CLASS" {
            DATATYPE  H5T_STRING {
               STRSIZE 6;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_0_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 7;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_1_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 7;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_2_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 8;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_3_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 10;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_4_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 5;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_5_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 11;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_6_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 12;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "TITLE" {
            DATATYPE  H5T_STRING {
               STRSIZE 14;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "VERSION" {
            DATATYPE  H5T_STRING {
               STRSIZE 4;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
      }
      DATASET "STATES" {
         DATATYPE  H5T_COMPOUND {
            H5T_STD_U32LE "CPU ID";
            H5T_STD_U16LE "APP ID";
            H5T_STD_U32LE "Task ID";
            H5T_STD_U32LE "Thread ID";
            H5T_STD_U64LE "Time ini";
            H5T_STD_U64LE "Time fi";
            H5T_STD_U16LE "State";
         }
         DATASPACE  SIMPLE { ( 301496 ) / ( H5S_UNLIMITED ) }
         ATTRIBUTE "CLASS" {
            DATATYPE  H5T_STRING {
               STRSIZE 6;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_0_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 7;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_1_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 7;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_2_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 8;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_3_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 10;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_4_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 9;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_5_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 8;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "FIELD_6_NAME" {
            DATATYPE  H5T_STRING {
               STRSIZE 6;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "TITLE" {
            DATATYPE  H5T_STRING {
               STRSIZE 14;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
         ATTRIBUTE "VERSION" {
            DATATYPE  H5T_STRING {
               STRSIZE 4;
               STRPAD H5T_STR_NULLTERM;
               CSET H5T_CSET_ASCII;
               CTYPE H5T_C_S1;
            }
            DATASPACE  SCALAR
         }
      }
   }
}
}