Netcdf Toolkit - ncinfo

Function File: info = ncinfo (filename)

Function File: info = ncinfo (filename, varname)

Function File: info = ncinfo (filename, groupname)

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.