Class NcVar
NcVar is derived from NcTypedComponent, and represents a netCDF
variable. A netCDF variable has a name, a type, a shape, zero or more
attributes, and a block of values associated with it. Because variables
are only associated with open netCDF files, there are no public
constructors for this class. Use member functions of NcFile to
get variables or add new variables.
Public Member Functions
NcToken name( void ) const-
Returns the name of the variable.
NcType type( void ) const-
Returns the type of the variable. The type will be one of
ncByte, ncChar, ncShort, ncInt,
ncFloat, or ncDouble.
int num_dims( void ) const- Returns number of dimensions for this variable.
NcDim* get_dim( int n ) const- Returns a pointer to the n-th dimension (starting at 0). Returns a
NULL-pointer if an invalid dimension is requested.
long* edges( void ) const- Returns the shape of the variable, in the form of a vector containing
the sizes of the dimensions of the variable. The caller is responsible
for deleting the returned edge vector when no longer needed.
int num_atts( void ) const- Returns the number of attributes attached to the variable.
NcAtt* get_att( NcToken attname ) const
NcAtt* get_att( int n ) const- The first member function returns a variable attribute by name. The
second returns the n-th (starting at 0) attribute of the variable. In
either case, if no such attribute has been attached to the variable,
zero is returned. Attributes returned in this way belong to the caller,
and hence should eventually be deleted by the caller to avoid memory
leaks.
NcBool is_valid( void ) const-
Returns
TRUE if the variable is valid, FALSE otherwise.
long num_vals( void ) const-
Returns the number of values for a variable. This is just 1 for a
scalar variable, or the product of the dimension sizes for all the
variable's dimensions.
NcValues* values( void ) const-
Returns a pointer to the block of all values for the variable.
The caller is responsible for deleting this block of values
when no longer needed.
Note that this is not a good way to read selected values of
a variable; use the
get member function instead, to get single
values or selected cross-sections of values.
NcBool put(const ncbyte* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const char* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const short* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const int* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const long* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const float* vals, long c0, long c1, long c2, long c3, long c4)NcBool put(const double* vals, long c0, long c1, long c2, long c3, long c4)-
Write scalar or 1 to 5-dimensional arrays by providing enough arguments.
Arguments are edge lengths, and their number must not exceed variable's
dimensionality. Start corner is
[0,0,..., 0] by default, but may
be reset using the set_cur() member function for this variable.
FALSE is returned if type of values does not match type for
variable. For more than 5 dimensions, use the overloaded n-dimensional
form of the put member function.
NcBool put(const ncbyte* vals, const long* counts)NcBool put(const char* vals, const long* counts)NcBool put(const short* vals, const long* counts)NcBool put(const int* vals, const long* counts)NcBool put(const long* vals, const long* counts)NcBool put(const float* vals, const long* counts)NcBool put(const double* vals, const long* counts)-
Write n-dimensional arrays, starting at
[0, 0, ..., 0] by
default, may be reset with set_cur(). FALSE is returned
if type of values does not match type for variable.
NcBool get(ncbyte* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(char* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(short* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(int* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(long* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(float* vals, long c0, long c1, long c2, long c3, long c4) constNcBool get(double* vals, long c0, long c1, long c2, long c3, long c4) const-
Get scalar or 1 to 5 dimensional arrays by providing enough arguments.
Arguments are edge lengths, and their number must not exceed variable's
dimensionality. Start corner is
[0,0,..., 0] by default, but may
be reset using the set_cur() member function. FALSE is
returned if type of values does not match type for variable.
NcBool get(ncbyte* vals, const long* counts) constNcBool get(char* vals, const long* counts) constNcBool get(short* vals, const long* counts) constNcBool get(int* vals, const long* counts) constNcBool get(long* vals, const long* counts) constNcBool get(float* vals, const long* counts) constNcBool get(double* vals, const long* counts) const- Get n-dimensional arrays, starting at
[0, 0, ..., 0] by default,
may be reset with set_cur() member function. FALSE is
returned if type of values does not match type for variable.
NcBool set_cur(long c0=-1, long c1=-1, long c2=-1, long c3=-1, long c4=-1)NcBool set_cur(long* cur)- Resets the starting corner to the values supplied. The first form works
for a variable of dimensionality from scalar to 5 dimensions. For more
than five dimensions, use the second form, in which the number of longfs
supplied must match the rank of the variable. The method returns FALSE if
any argument is greater than the size of the corresponding dimension.
NcBool add_att( NcToken, char )
NcBool add_att( NcToken, ncbyte )NcBool add_att( NcToken, short )NcBool add_att( NcToken, int )NcBool add_att( NcToken, long )NcBool add_att( NcToken, float )NcBool add_att( NcToken, double )NcBool add_att( NcToken, const char* )NcBool add_att( NcToken, int, const char* )NcBool add_att( NcToken, int, const ncbyte* )NcBool add_att( NcToken, int, const short* )NcBool add_att( NcToken, int, const int* )NcBool add_att( NcToken, int, const long* )NcBool add_att( NcToken, int, const float* )NcBool add_att( NcToken, int, const double* )-
Add scalar or vector attribute of any type to a variable, given the
name, number of values, and the vector of values. These put file in
define mode, so could be expensive. To avoid the expense of copying
data, add attributes to variables before writing data.
NcBool rename( NcToken newname )-
Renames the variable. If variable is renamed to a longer name, this
puts file in define mode, so could be expensive.
ncbyte as_ncbyte( int n ) constchar as_char( int n ) constshort as_short( int n ) constint as_int( int n ) constnclong as_nclong( int n ) const // deprecatedlong as_long( int n ) constfloat as_float( int n ) constdouble as_double( int n ) constchar* as_string( int n ) const-
Get the n-th value of the variable, ignoring its shape. These member
functions provide conversions from the value type of the variable to the
specified type. If the requested value is out-of-range, the fill-value of the
appropriate type is returned.
int id( void ) const-
Return the variable number. This is not needed in the C++ interface,
but might be needed in calling a C-function that requires that a variable
be identified by number instead of name.
NcBool sync( void )-
If the variable may have been renamed, make sure its name is updated.
~NcVar( void )- Destructor.
The following member functions are intended for record variables. They
will also work for non-record variables, if the first dimension is
interpreted as the record dimension.
long rec_size( void )
long rec_size( NcDim* )-
Return the number of values per record or the number of values per
dimension slice for the specified dimension.
NcValues* get_rec( void )NcValues* get_rec( long n )-
Get the data for this variable for the current record or for the
nth record.
NcValues* get_rec( NcDim* )NcValues* get_rec( NcDim*, long n )-
Get the data for this variable for the current dimension slice or for the
nth dimension slice.
NcBool put_rec( const ncbyte* vals )NcBool put_rec( const char* vals )NcBool put_rec( const short* vals )NcBool put_rec( const int* vals )NcBool put_rec( const long* vals )NcBool put_rec( const float* vals )NcBool put_rec( const double* vals )-
Put a record's worth of data for this variable in the current record.
NcBool put_rec( NcDim*, const ncbyte* vals )NcBool put_rec( NcDim*, const char* vals )NcBool put_rec( NcDim*, const short* vals )NcBool put_rec( NcDim*, const int* vals )NcBool put_rec( NcDim*, const long* vals )NcBool put_rec( NcDim*, const float* vals )NcBool put_rec( NcDim*, const double* vals )-
Put a dimension slice worth of data for this variable in the current
dimension slice.
NcBool put_rec( const ncbyte* vals, long rec )NcBool put_rec( const char* vals, long rec )NcBool put_rec( const short* vals, long rec )NcBool put_rec( const int* vals, long rec )NcBool put_rec( const long* vals, long rec )NcBool put_rec( const float* vals, long rec )NcBool put_rec( const double* vals, long rec )-
Put a record's worth of data for this variable in the specified record.
NcBool put_rec( NcDim*, const ncbyte* vals, long slice )NcBool put_rec( NcDim*, const char* vals, long slice )NcBool put_rec( NcDim*, const short* vals, long slice )NcBool put_rec( NcDim*, const int* vals, long slice )NcBool put_rec( NcDim*, const long* vals, long slice )NcBool put_rec( NcDim*, const float* vals, long slice )NcBool put_rec( NcDim*, const double* vals, long slice )-
Put a dimension slice worth of data for this variable in the specified
dimension slice.
long get_index( const ncbyte* vals )long get_index( const char* vals )long get_index( const short* vals )long get_index( const int* vals )long get_index( const long* vals )long get_index( const float* vals )long get_index( const double* vals )-
Get first record index for this variable corresponding to the specified
key value(s).
long get_index( NcDim*, const ncbyte* vals )long get_index( NcDim*, const char* vals )long get_index( NcDim*, const short* vals )long get_index( NcDim*, const int* vals )long get_index( NcDim*, const long* vals )long get_index( NcDim*, const float* vals )long get_index( NcDim*, const double* vals )-
Get first index of specified dimension for this variable corresponding
to the specified key value(s).
void set_rec ( long rec )-
Set the current record for this variable.
void set_rec ( NcDim*, long rec )-
Set the current dimension slice for the specified dimension for this variable.
