Module netCDF4 :: Class UserType
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Class UserType



object --+
         |
        UserType

A UserType instance is used to describe some of the new data types supported in netCDF 4. Currently, 'vlen' and 'compound' data types can be described by instances of the UserType class.

Constructor: UserType(group, base_datatype, usertype, usertype_name)

UserType instances should be created using the createUserType method of a Dataset or Group instance, not using this class directly.

Parameters:

group - Group instance to associate with user-defined datatype.

base_datatype - Base data type (data type that user-defined data type is composed of). For usertype='vlen', can be one of 'f4' (32-bit floating point), 'f8' (64-bit floating point), 'i4' (32-bit signed integer), 'i2' (16-bit signed integer), 'i8' (64-bit singed integer), 'i1' (8-bit signed integer), 'u1' (8-bit unsigned integer), 'u2' (16-bit unsigned integer), 'u4' (32-bit unsigned integer), 'u8' (64-bit unsigned integer), or 'S1' (single-character string). For usertype='compound', the base_datatype argument must be a list of 3-element tuples describing the type of each member of the compound type. Each 3-tuple must contain a string giving the name of the member, a string describing the primitive data-type of the member ('i4','f8', etc. - 'S' not allowed) and a tuple describing the member's shape. The same format can be used to create a dtype descriptor for a numpy record array.

usertype - The type of user-defined data type (such as 'vlen', 'compound', 'opaque' or 'enum'). Currently, only 'vlen' and 'compound' are supported. In netCDF 4 it is possible to have nested user-defined data types (e.g. compound types composed of vlens), but this is not yet supported. All user-defined data types must consist of collections of fixed-size primitive data types (as specified by the base_datatype argument).

usertype_name - a Python string containing a description of the user-defined data type.

Returns:

a UserType instance, which can be passed to the createVariable method of a Dataset or Group instance.

The instance variables usertype, usertype_name and base_datatype are read-only (and should not be modified by the user).

Instance Methods [hide private]
  __init__(...)
x.__init__(...) initializes x; see x.__class__.__doc__ for signature
  __new__(T, S, ...)

Inherited from object: __delattr__, __getattribute__, __hash__, __reduce__, __reduce_ex__, __repr__, __setattr__, __str__


Class Variables [hide private]
  _base_type_offsets = <member '_base_type_offsets' of 'netCDF4.UserType' o...
  _base_type_size = <member '_base_type_size' of 'netCDF4.UserType' obje...
  _base_type_sizes = <member '_base_type_sizes' of 'netCDF4.UserType' obj...
  _grpid = <member '_grpid' of 'netCDF4.UserType' objects>
  _nc_type = <member '_nc_type' of 'netCDF4.UserType' objects>
  _nfields = <member '_nfields' of 'netCDF4.UserType' objects>

Instance Variables [hide private]
  base_datatype = <member 'base_datatype' of 'netCDF4.UserType' objects>
Describes the data type of which the user-defined data type is composed - given by the base_datatype argument to the UserType constructor.
  usertype = <member 'usertype' of 'netCDF4.UserType' objects>
Describes the user-defined data type (either 'vlen' or 'compound') - given by the usertype argument to the UserType constructor..
  usertype_name = <member 'usertype_name' of 'netCDF4.UserType' objects>
User-specified name (python string) for the user-defined data type - given by the usertype_name argument to the UserType constructor.

Properties [hide private]

Inherited from object: __class__


Method Details [hide private]

__init__(...)
(Constructor)

 
x.__init__(...) initializes x; see x.__class__.__doc__ for signature
Overrides: object.__init__

__new__(T, S, ...)

 
Returns:
a new object with type S, a subtype of T

Overrides: object.__new__

Class Variable Details [hide private]

_base_type_offsets

None
Value:
<member '_base_type_offsets' of 'netCDF4.UserType' objects>            
      

_base_type_size

None
Value:
<member '_base_type_size' of 'netCDF4.UserType' objects>               
      

_base_type_sizes

None
Value:
<member '_base_type_sizes' of 'netCDF4.UserType' objects>              
      

_grpid

None
Value:
<member '_grpid' of 'netCDF4.UserType' objects>                        
      

_nc_type

None
Value:
<member '_nc_type' of 'netCDF4.UserType' objects>                      
      

_nfields

None
Value:
<member '_nfields' of 'netCDF4.UserType' objects>                      
      

Instance Variable Details [hide private]

base_datatype

Describes the data type of which the user-defined data type is composed - given by the base_datatype argument to the UserType constructor.
Value:
<member 'base_datatype' of 'netCDF4.UserType' objects>                 
      

usertype

Describes the user-defined data type (either 'vlen' or 'compound') - given by the usertype argument to the UserType constructor..
Value:
<member 'usertype' of 'netCDF4.UserType' objects>                      
      

usertype_name

User-specified name (python string) for the user-defined data type - given by the usertype_name argument to the UserType constructor.
Value:
<member 'usertype_name' of 'netCDF4.UserType' objects>