Look Up Hierarchy and Data API

These APIs simply look up hierarchy array constructed by libyt or look up data pointer that is passed in by user and wrapped by libyt.

These APIs are only available after yt_commit is called.

yt_getGridInfo_Dimensions

int yt_getGridInfo_Dimensions( const long gid, int (*dimensions)[3] );

• Usage: Get dimension of grid gid. dimensions[0] corresponds to dimension in x-axis, dimensions[1] corresponds to dimension in y-axis, and dimensions[2] corresponds to dimension in z-axis, excluding ghost cells.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_LeftEdge

int yt_getGridInfo_LeftEdge(const long gid, double (*left_edge)[3]);

• Usage: Get left edge of grid gid. left_edge[0] is left edge of the grid in x-axis in code length, left_edge[1] for y-axis, and left_edge[2] for z-axis.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_RightEdge

int yt_getGridInfo_RightEdge(const long gid, double (*right_edge)[3]);

• Usage: Get right edge of grid gid. right_edge[0] is right edge of the grid in x-axis in code length, right_edge[1] for y-axis, and right_edge[2] for z-axis.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_ParentId

int yt_getGridInfo_ParentId(const long gid, long *parent_id);

• Usage: Get parent grid id of grid gid. If there is no parent grid, parent_id will be -1.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_Level

int yt_getGridInfo_Level(const long gid, int *level);

• Usage: Get level of grid gid. If grids are on root level, level will be 0.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_ProcNum

int yt_getGridInfo_ProcNum(const long gid, int *proc_num);

• Usage: Get MPI process number (MPI rank) of grid gid located on.
• Return: YT_SUCCESS or YT_FAIL

yt_getGridInfo_ParticleCount

int yt_getGridInfo_ParticleCount(const long gid, const char *ptype, long *par_count);

• Usage: Get number of particle ptype located on grid gid.
• Return: YT_SUCCESS or YT_FAIL

  Particle type name ptype should be same as what you passed in yt_get_ParticlesPtr.

yt_getGridInfo_FieldData

int yt_getGridInfo_FieldData(const long gid, const char *field_name, yt_data *field_data);

• Usage: Get the field data field_name in grid id gid. The result will be stored in field_data.
• Return: YT_SUCCESS or YT_FAIL if it cannot get data.
• yt_data
  • data_ptr: Data pointer.
  • data_dimensions[3]: Dimension of the data_ptr array, in the point of view of itself.
  • data_dtype: Data type of the array.

Field name field_name should be same as what you passed in yt_get_FieldsPtr.

Do not mix grid dimensions get through yt_getGridInfo_Dimensions with data dimensions get through yt_getGridInfo_FieldData. Grid dimensions are numbers of cells in [x][y][z] <–> [0][1][2], excluding ghost cells. Whereas data dimensions are just data length in data’s point of view, which may consist of ghost cells.

You should not modify data_ptr, because they are actual simulation data passed in by user when setting grid information yt_get_GridsPtr.

yt_getGridInfo_ParticleData

int yt_getGridInfo_ParticleData(const long gid, const char *ptype, const char *attr, yt_data *par_data);

• Usage: Get the particle data ptype attribute attr in grid id gid. The result will be stored in par_data.
• Return: YT_SUCCESS or YT_FAIL if it cannot get data.
• yt_data
  • data_ptr: Data pointer.
  • data_dimensions[3]: Dimension of the data_ptr array, in the point of view of itself. If data_ptr is a 1-dim array, the last two elements will be 0.
  • data_dtype: Data type of the array.

Particle type ptype and attribute attr should be the same as what you passed in yt_get_ParticlesPtr.

You should not modify data_ptr, because they are actual simulation data passed in by user when setting grid information yt_get_GridsPtr.