Return information about an entire NetCDF file filename (i.e. the root
group "/"), about the variable called varname or the group called
groupname.
The structure info has always the following fields:
- Filename: the name of the NetCDF file
- Format: one of the strings "CLASSIC", "64BIT", "NETCDF4"
or "NETCDF4_CLASSIC"
The structure info has additional fields depending on whether a
group of variable is queried.
Groups ¶
Groups are returned as an array structure with the following fields:
- Name: the group name. The root group is named "/".
- Dimensions: a array structure with the dimensions.
- Variables: a array structure with the variables.
- Attributes: a array structure with global attributes.
- Groups: a array structure (one for each group) with the
same fields as this structure.
Dimensions ¶
Dimensions are returned as an array structure with the following fields:
- Name: the name of the dimension
- Length: the length of the dimension
- Unlimited: true of the dimension has no fixed limited, false
Variables ¶
Variables are returned as an array structure with the following fields:
- Name: the name of the dimension
- Dimensions: array structure of all dimensions of this variable
with the same structure as above.
- Size: array with the size of the variable
- Datatype: string with the corresponding octave data-type
(see below)
- Attributes: a array structure of attributes
- FillValue: the NetCDF fill value of the variable. If the fill
value is not defined, then this attribute is an empty array ([]).
- DeflateLevel: the NetCDF deflate level between 0 (no
compression) and 9 (maximum compression).
- Shuffle: is true if the shuffle filter is activated to improve
compression, otherwise false.
- CheckSum: is set to "fletcher32", if check-sums are used,
otherwise this field is not defined.
Attributes ¶
Attributes are returned as an array structure with the following fields:
- Name: the name of the attribute
- Value: the value of the attribute (with the corresponding type)
- Unlimited: true of the dimension has no fixed limited, false
Data-types ¶
The following the the correspondence between the Octave and NetCDF
data-types:
Octave type | NetCDF type |
int8 | NC_BYTE |
uint8 | NC_UBYTE |
int16 | NC_SHORT |
uint16 | NC_USHORT |
int32 | NC_INT |
uint32 | NC_UINT |
int64 | NC_INT64 |
uint64 | NC_UINT64 |
single | NC_FLOAT |
double | NC_DOUBLE |
char | NC_CHAR |
The output of ncinfo
can be used to create a NetCDF file with the same
meta-data using ncwriteschema
.
Note: If there are no attributes (or variable or groups), the corresponding
field is an empty matrix and not an empty struct array for compatibility
with matlab.
See also: ncread,nccreate,ncwriteschema,ncdisp.