Routines (alphabetical) > Routines: H > HDF5 Routines > H5A_WRITE

# H5A_WRITE

The H5A_WRITE procedure writes data to an attribute.

## Example

See the example under H5F_CREATE.

## Syntax

H5A_WRITE, Attribute_id, Data

## Arguments

### Attribute_id

An integer giving the identifier of the attribute to which to write the data.

### Data

The data to be written. The following table shows how IDL data types are converted to HDF5 datatypes. Pointers, complex numbers, and object references cannot be written to HDF5 attributes. Data passed in via IDL will automatically be converted into the output data type if possible.

IDL Data Type | HDF5 Data Type
Byte | H5T_NATIVE_UINT8
Integer | H5T_NATIVE_INT16
Unsigned integer | H5T_NATIVE_UINT16
Long integer | H5T_NATIVE_INT32
Unsigned long integer | H5T_NATIVE_UINT32
64-bit Integer | H5T_NATIVE_INT64
Unsigned 64-bit integer | H5T_NATIVE_UINT64
Floating point | H5T_NATIVE_FLOAT
Double-precision floating | H5T_NATIVE_DOUBLE
String | H5T_C_S1
Reference Structure | H5T_REFERENCE
Structure | (Member datatypes)

Note: The reference structure is returned from H5R_CREATE.

## Keywords

None

## Version History

6.2 | Introduced

## See Also

H5A_CREATE, H5S_CREATE_SIMPLE, H5T_IDL_CREATE, H5T_REFERENCE_CREATE