[HDF]hdf-4.2.6类库的使用

　　HDF文件包括科学数据和VData部分。读取HDF格式的calipso数据，用GDAL可以方便的读取其中的子数据集，但是没有发现GDAL中提供读取Vdata的方法。所以只好考虑借助hdf-4.2.6类库本身。毕竟GDAL也是采用的hdf-4.2.6类库进行了一次封装。

首先从HdfGroup网站下载一个编译好的安装包。解压后目录如下：

新建一个Win32控制台项目。

添加包含和引用的lib，注意安装目录文件夹下的lib文件夹中的.lib文件应该是relese版本的，我这里引用了dll文件夹下的.lib文件。

从Hdf4.2.6源码中找到VD_create_onefield_vdatas.c文件。我这里修改为VD_create_onefield_vdatas.cpp，添加到项目中，把项目中的HdfFirst.cpp直接排除掉，因为里面有个Main函数。

同时在VD_create_onefield_vdatas.cpp添加

#include "stdafx.h"

完整代码：

 1 #include "stdafx.h"
 2 #include "hdf.h" 
 3 
 4 #define  FILE_NAME      "General_Vdatas.hdf"
 5 #define  CLASS1_NAME    "5x1 Array"
 6 #define  CLASS2_NAME    "6x4 Array"
 7 #define  VDATA1_NAME    "First Vdata"
 8 #define  VDATA2_NAME    "Second Vdata"
 9 #define  FIELD1_NAME    "Single-component Field"
10 #define  FIELD2_NAME    "Multi-component Field"
11 #define  N_RECORDS_1    5    /* number of records the first vdata contains  */
12 #define  N_RECORDS_2    6    /* number of records the second vdata contains */
13 #define  ORDER_2        4    /* order of the field in the second vdata      */
14                 /* Note that the order of the field in the first vdata is 1 */
15 
16 int main( )
17 {
18    /************************* Variable declaration **************************/
19 
20    intn  status_n;      /* returned status for functions returning an intn  */
21    int32 status_32;     /* returned status for functions returning an int32 */
22    int32 file_id, vdata1_ref, vdata2_ref; 
23 
24    /*
25    * Define an array to buffer the data of the first vdata.
26    */
27    char8 vdata1_buf [N_RECORDS_1] = {'V', 'D', 'A', 'T', 'A'};
28 
29    /*
30    * Define an array to buffer the data of the second vdata.
31    */
32    int32 vdata2_buf [N_RECORDS_2][ORDER_2] = {{1, 2, 3, 4}, {2, 4, 6, 8},
33                                               {3, 6, 9, 12}, {4, 8, 12, 16},
34                                               {5, 10, 15, 20}, {6, 12, 18, 24}};
35 
36    /********************** End of variable declaration **********************/
37 
38    /*
39    * Open the HDF file for writing.
40    */
41    file_id = Hopen (FILE_NAME, DFACC_WRITE, 0);
42 
43    /*
44    * Initialize the VS interface.
45    */
46    status_n = Vstart (file_id);
47     
48    /*
49    * Create the first vdata and populate it with data from the vdata1_buf 
50    * array. Note that the buffer vdata1_buf is cast to (uint8 *) for the 
51    * benefit of generic data type.
52    */
53    vdata1_ref = VHstoredata (file_id, FIELD1_NAME, (uint8 *)vdata1_buf, 
54                        N_RECORDS_1, DFNT_CHAR8, VDATA1_NAME, CLASS1_NAME); 
55 
56    /* 
57    * Create the second vdata and populate it with data from the vdata2_buf 
58    * array. 
59    */
60    vdata2_ref = VHstoredatam (file_id, FIELD2_NAME, (uint8 *)vdata2_buf, 
61                N_RECORDS_2, DFNT_INT32, VDATA2_NAME, CLASS2_NAME, ORDER_2); 
62 
63    /* 
64    * Terminate access to the VS interface and close the HDF file.
65    */
66    status_n = Vend (file_id);
67    status_32 = Hclose (file_id);
68    return 0;
69 }