H5Tset_cset(
hid_t dtype_id,
H5T_cset_t cset
)
H5Tset_cset sets the character set to be used
in a dataset with a string or character datatype.
Valid values for cset include the following:
H5T_CSET_ASCII
| Character set is US ASCII. | ||
H5T_CSET_UTF8
| Character set is UTF-8, enabling UTF-8 Unicode encoding. |
For example, if the character set for the datatype
dtype_id is set to
H5T_CSET_UTF8,
string or character data of datatype dtype_id
will be encoded using the UTF-8 Unicode character set.
ASCII and UTF-8 Unicode are the only currently supported character encodings. Extended ASCII encodings (for example, ISO 8859) are not supported. This encoding policy is not enforced by the HDF5 Library. Using encodings other than ASCII and UTF-8 can lead to compatibility and usability problems.
Note that H5Tset_cset sets the character set for
a character or string datatype while
H5Pset_char_encoding
sets the character set used for an HDF5 link or attribute name.
hid_t dtype_id |
IN: Identifier of datatype to modify. |
H5T_cset_t cset |
IN: Character set type. |
SUBROUTINE h5tset_cset_f(type_id, cset, hdferr)
IMPLICIT NONE
INTEGER(HID_T), INTENT(IN) :: type_id
! Datatype identifier
INTEGER, INTENT(IN) :: cset ! Character set type of a string datatype
! Possible values are:
! H5T_CSET_ASCII_F = 0
! H5T_CSET_UTF8_F = 1
INTEGER, INTENT(OUT) :: hdferr ! Error code
END SUBROUTINE h5tset_cset_f
| Release | Change |
| 1.8.0 | UTF-8 Unicode encoding introduced in this release. |
- Last modified: 19 August 2010
- Name: H5Tset_ebias
- Signature:
- Name: H5Tset_ebias
- herr_t
H5Tset_ebias( hid_tdtype_id, size_tebias) - Purpose:
- Sets the exponent bias of a floating-point type.
- Description:
H5Tset_ebiassets the exponent bias of a floating-point type.- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. size_t ebiasIN: Exponent bias value. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_ebias_f
-
SUBROUTINE h5tset_ebias_f(type_id, ebias, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER(SIZE_T), INTENT(IN) :: ebias ! Datatype exponent bias ! of a floating-point type, ! which cannot be 0 INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_ebias_f
- Last modified: 19 August 2010
- Name: H5Tset_fields
- Signature:
- Name: H5Tset_fields
- herr_t
H5Tset_fields( hid_tdtype_id, size_tspos, size_tepos, size_tesize, size_tmpos, size_tmsize) - Purpose:
- Sets locations and sizes of floating point bit fields.
- Description:
H5Tset_fieldssets the locations and sizes of the various floating-point bit fields. The field positions are bit positions in the significant region of the datatype. Bits are numbered with the least significant bit number zero.Fields are not allowed to extend beyond the number of bits of precision, nor are they allowed to overlap with one another.
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. size_t sposIN: Sign position, i.e., the bit offset of the floating-point sign bit. size_t eposIN: Exponent bit position. size_t esizeIN: Size of exponent in bits. size_t mposIN: Mantissa bit position. size_t msizeIN: Size of mantissa in bits. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_fields_f
-
SUBROUTINE h5tset_fields_f(type_id, spos, epos, esize, mpos, msize, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER(SIZE_T), INTENT(IN) :: spos ! sign bit-position INTEGER(SIZE_T), INTENT(IN) :: epos ! exponent bit-position INTEGER(SIZE_T), INTENT(IN) :: esize ! size of exponent in bits INTEGER(SIZE_T), INTENT(IN) :: mpos ! mantissa bit-position INTEGER(SIZE_T), INTENT(IN) :: msize ! size of mantissa in bits INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_fields_f
- Name: H5Tset_inpad
- Signature:
- herr_t
H5Tset_inpad( hid_tdtype_id, H5T_pad_tinpad) - Purpose:
- Fills unused internal floating point bits.
- Description:
- If any internal bits of a floating point type are unused
(that is, those significant bits which are not part of the
sign, exponent, or mantissa), then
H5Tset_inpadwill be filled according to the value of the padding value propertyinpad. Valid padding types are:- H5T_PAD_ZERO (
0) - Set background to zeros.
- H5T_PAD_ONE (
1) - Set background to ones.
- H5T_PAD_BACKGROUND (
2) - Leave background alone.
- H5T_PAD_ZERO (
- Parameters:
hid_t dtype_idIdentifier of datatype to modify. H5T_pad_t padPadding type. - Returns:
- Returns a non-negative value if successful; otherwise returns a negative value.
- Fortran90 Interface: h5tset_inpad_f
-
SUBROUTINE h5tset_inpad_f(type_id, padtype, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: padtype ! Padding type for unused bits ! in floating-point datatypes. ! Possible values of padding type are: ! H5T_PAD_ZERO_F = 0 ! H5T_PAD_ONE_F = 1 ! H5T_PAD_BACKGROUND_F = 2 INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_inpad_f
- Last modified: 19 August 2010
- Name: H5Tset_norm
- Signature:
- Name: H5Tset_norm
- herr_t
H5Tset_norm( hid_tdtype_id, H5T_norm_tnorm) - Purpose:
- Sets the mantissa normalization of a floating-point datatype.
- Description:
H5Tset_normsets the mantissa normalization of a floating-point datatype. Valid normalization types are:- H5T_NORM_IMPLIED (
0) - MSB of mantissa is not stored, always 1.
- H5T_NORM_MSBSET (
1) - MSB of mantissa is always 1.
- H5T_NORM_NONE (
2) - Mantissa is not normalized.
- H5T_NORM_IMPLIED (
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. H5T_norm_t normIN: Mantissa normalization type. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_norm_f
-
SUBROUTINE h5tset_norm_f(type_id, norm, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: norm ! Mantissa normalization of a ! floating-point datatype ! Valid normalization types are: ! H5T_NORM_IMPLIED_F(0) ! MSB of mantissa is not stored, ! always 1 ! H5T_NORM_MSBSET_F(1) ! MSB of mantissa is always 1 ! H5T_NORM_NONE_F(2) ! Mantissa is not normalized INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_norm_f
- Last modified: 19 August 2010
- Name: H5Tset_offset
- Signature:
- Name: H5Tset_offset
- herr_t
H5Tset_offset( hid_tdtype_id, size_toffset) - Purpose:
- Sets the bit offset of the first significant bit.
- Description:
H5Tset_offsetsets the bit offset of the first significant bit. The significant bits of an atomic datum can be offset from the beginning of the memory for that datum by an amount of padding. Theoffsetproperty specifies the number of bits of padding that appear “to the right of” the value. That is, if we have a 32-bit datum with 16-bits of precision having the value0x1122, then it will be laid out in memory as (from small byte address toward larger byte addresses):
Byte Position Big-Endian Offset=0 Big-Endian Offset=16 Little-Endian Offset=0 Little-Endian Offset=16 0 [ pad] [0x11] [0x22] [ pad] 1 [ pad] [0x22] [0x11] [ pad] 2 [0x11] [ pad] [ pad] [0x22] 3 [0x22] [ pad] [ pad] [0x11] If the offset is incremented then the total size is incremented also if necessary to prevent significant bits of the value from hanging over the edge of the datatype.
The offset of an H5T_STRING cannot be set to anything but zero.
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. size_t offsetIN: Offset of first significant bit. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_offset_f
-
SUBROUTINE h5tset_offset_f(type_id, offset, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER(SIZE_T), INTENT(IN) :: offset ! Datatype bit offset of ! the first significant bit INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_offset_f
- Last modified: 24 September 2010
- Name: H5Tset_order
- Signature:
- Name: H5Tset_order
- herr_t
H5Tset_order( hid_tdtype_id, H5T_order_torder) - Purpose:
- Sets the byte order of a datatype.
- Description:
H5Tset_ordersets the byte order of a datatype.Byte order can currently be set to any of the following:
H5T_ORDER_LE(0)- Little-endian byte order
H5T_ORDER_BE(1)- Big-endian byte order
H5T_ORDER_VAX(2)- VAX mixed byte order
H5T_ORDER_MIXED(3) is a valid value fororderonly when returned by the functionH5Tget_order; it cannot be set withH5Tset_order.H5T_ORDER_NONE(4) is a valid value fororder, but it has no effect. It is valid only for fixed-length strings and object and region references and specifies “no particular order.”The byte order of a derived datatype is initially the same as that of the parent type, but can be changed with
H5Tset_order.This function cannot be used with a datatype after it has been committed.
Special considerations:
ENUM datatypes: Byte order must be set before any member on an ENUM is defined.Compound datatypes: Byte order is set individually on each member of a compound datatype; members of a compound datatype need not have the same byte order.
Opaque datatypes: Byte order can be set but has no effect.
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. H5T_order_t orderIN: Byte order constant. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_order_f
-
SUBROUTINE h5tset_order_f(type_id, order, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: order ! Datatype byte order ! Possible values are: ! H5T_ORDER_LE_F ! H5T_ORDER_BE_F ! H5T_ORDER_VAX_F ! H5T_ORDER_NONE_F INTEGER, INTENT(OUT) :: hdferr ! Error code ! 0 on success and -1 on failure END SUBROUTINE h5tset_order_f - History:
Release Change 1.8.6 Function modified to work with all datatypes.
H5T_ORDER_MIXEDadded toH5T_order_t.
- Last modified: 19 August 2010
- Name: H5Tset_pad
- Signature:
- Name: H5Tset_pad
- herr_t
H5Tset_pad( hid_tdtype_id, H5T_pad_tlsb, H5T_pad_tmsb) - Purpose:
- Sets the least and most-significant bits padding types.
- Description:
H5Tset_padsets the least and most-significant bits padding types.- H5T_PAD_ZERO (
0) - Set background to zeros.
- H5T_PAD_ONE (
1) - Set background to ones.
- H5T_PAD_BACKGROUND (
2) - Leave background alone.
- H5T_PAD_ZERO (
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. H5T_pad_t lsbIN: Padding type for least-significant bits. H5T_pad_t msbIN: Padding type for most-significant bits. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_pad_f
-
SUBROUTINE h5tset_pad_f(type_id, lsbpad, msbpad, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: lsbpad ! Padding type of the ! least significant bit INTEGER, INTENT(IN) :: msbpad ! Padding type of the ! most significant bit ! Possible values of padding ! type are: ! H5T_PAD_ZERO_F = 0 ! H5T_PAD_ONE_F = 1 ! H5T_PAD_BACKGROUND_F = 2 ! H5T_PAD_ERROR_F = -1 ! H5T_PAD_NPAD_F = 3 INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_pad_f
- Last modified: 19 August 2010
- Name: H5Tset_precision
- Signature:
- Name: H5Tset_precision
- herr_t
H5Tset_precision( hid_tdtype_id, size_tprecision) - Purpose:
- Sets the precision of an atomic datatype.
- Description:
H5Tset_precisionsets the precision of an atomic datatype. The precision is the number of significant bits which, unless padding is present, is 8 times larger than the value returned byH5Tget_size.If the precision is increased then the offset is decreased and then the size is increased to insure that significant bits do not "hang over" the edge of the datatype.
Changing the precision of an H5T_STRING automatically changes the size as well. The precision must be a multiple of 8.
When decreasing the precision of a floating point type, set the locations and sizes of the sign, mantissa, and exponent fields first.
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. size_t precisionIN: Number of bits of precision for datatype. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_precision_f
-
SUBROUTINE h5tset_precision_f(type_id, precision, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER(SIZE_T), INTENT(IN) :: precision ! Datatype precision INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_precision_f
- Last modified: 19 August 2010
- Name: H5Tset_sign
- Signature:
- Name: H5Tset_sign
- herr_t
H5Tset_sign( hid_tdtype_id, H5T_sign_tsign) - Purpose:
- Sets the sign property for an integer type.
- Description:
H5Tset_signsets the sign property for an integer type:-
H5T_SGN_NONE(0)Unsigned integer type H5T_SGN_2(1)Two's complement signed integer type
-
- Parameters:
hid_t dtype_idIN: Identifier of datatype to set. H5T_sign_t signIN: Sign type. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_sign_f
-
SUBROUTINE h5tset_sign_f(type_id, sign, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: sign ! Sign type for an integer type ! Possible values are: ! Unsigned integer type ! H5T_SGN_NONE_F = 0 ! Two's complement signed integer type ! H5T_SGN_2_F = 1 ! or error value ! H5T_SGN_ERROR_F=-1 INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_sign_f
- Last modified: 7 April 2014
- Name: H5Tset_size
- Signature:
- Name: H5Tset_size
- herr_t
H5Tset_size( hid_tdtype_id, size_tsize) - Purpose:
- Sets the total size for a datatype.
- Description:
H5Tset_sizesets the total size in bytes,size, for a datatype.The parameter
sizemust have a positive value, unless it is passed asH5T_VARIABLEand the datatype is a string datatype.Numeric datatypes: If the datatype is atomic and the size is decreased so that significant bits of the datatype extend beyond the edge of the new size, then the
offsetproperty of the datatype is decreased toward zero. If theoffsetbecomes zero and the significant bits of the datatype still hang over the edge of the new size, then the number of significant bits is decreased.String or character datatypes: The
sizeset for a string datatype should include space for the null-terminator character, otherwise it will not be stored on (or retrieved from) disk. Adjusting thesizeof a string automatically sets the precision to 8*size.Variable-length string datatypes: If
dtype_idis a variable-length string,sizemust normally be set toH5T_VARIABLE. See “Creating variable-length string datatypes”.Compound datatypes: This function may be used to increase or decrease the size of a compound datatype, but the function will fail if the new size is too small to accommodate all member fields.
Ineligible datatypes: This function cannot be used with enumerated datatypes (
H5T_ENUM), array datatypes (H5T_ARRAY), variable-length array datatypes (H5T_VLEN), or reference datatypes (H5T_REFERENCE).- Parameters:
hid_t dtype_idIN: Identifier of datatype for which the size is being changed size_t sizeIN: New datatype size in bytes or H5T_VARIABLE- Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- See Also:
- “Creating
variable-length string datatypes”
- Fortran90 Interface: h5tset_size_f
-
SUBROUTINE h5tset_size_f(type_id, size, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER(SIZE_T), INTENT(IN) :: size ! Datatype size INTEGER, INTENT(OUT) :: hdferr ! Error code ! 0 on success and -1 on failure END SUBROUTINE h5tset_size_f
- Last modified: 16 April 2013
- Name: H5Tset_strpad
- Signature:
- Name: H5Tset_strpad
- herr_t
H5Tset_strpad( hid_tdtype_id, H5T_str_tstrpad) - Purpose:
- Defines the type of padding used for character strings.
- Description:
H5Tset_strpaddefines the type of padding used for a string datatype.The method used to store character strings differs with the programming language:
- C usually null terminates strings while
- Fortran left-justifies and space-pads strings.
Valid values of
strpadare as follows:H5T_STR_NULLTERM(0)- Null terminate (as C does).
H5T_STR_NULLPAD(1)- Pad with zeros.
H5T_STR_SPACEPAD(2)- Pad with spaces (as FORTRAN does).
When converting from a longer string to a shorter string, the behavior is as follows. If the shorter string is
H5T_STR_NULLPADorH5T_STR_SPACEPAD, then the string is simply truncated. If the short string isH5T_STR_NULLTERM, it is truncated and a null terminator is appended.When converting from a shorter string to a longer string, the longer string is padded on the end by appending nulls or spaces.
- Parameters:
hid_t dtype_idIN: Identifier of datatype to modify. H5T_str_t strpadIN: String padding type. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface: h5tset_strpad_f
-
SUBROUTINE h5tset_strpad_f(type_id, strpad, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier INTEGER, INTENT(IN) :: strpad ! String padding method for a string datatype ! Possible values of padding type are: ! Pad with zeros (as C does): ! H5T_STR_NULLPAD_F(0) ! Pad with spaces (as FORTRAN does): ! H5T_STR_SPACEPAD_F(1) INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_strpad_f
- Name: H5Tset_tag
- Signature:
- herr_t
H5Tset_tag( hid_tdtype_idconst char *tag) - Purpose:
- Tags an opaque datatype.
- Description:
H5Tset_tagtags an opaque datatypedtype_idwith a descriptive ASCII identifier,tag.tagis intended to provide a concise description; the maximum size is hard-coded in the HDF5 Library as 256 bytes (H5T_OPAQUE_TAG_MAX).- Parameters:
hid_t dtype_idIN: Datatype identifier for the opaque datatype to be tagged. const char * tagIN: Descriptive ASCII string with which the opaque datatype is to be tagged. - Returns:
- Returns a non-negative value if successful; otherwise returns a negative value.
- Fortran90 Interface: h5tset_tag_f
-
SUBROUTINE h5tset_tag_f(type_id, tag, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier CHARACTER(LEN=*), INTENT(IN) :: tag ! Unique ASCII string with which the ! opaque datatype is to be tagged INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tset_tag_f - History:
Release C 1.6.5 The H5T_OPAQUE_TAG_MAXmacro constant, specifying the maximum size of an opaque datatype tag, was added inH5Tpublic.h.
- Last modified: 19 August 2010
- Name: H5Tunregister
- Signature:
- Name: H5Tunregister
- herr_t
H5Tunregister( H5T_pers_ttype, const char *name, hid_tsrc_id, hid_tdst_id, H5T_conv_tfunc) - Purpose:
- Removes a conversion function.
- Description:
H5Tunregisterremoves a conversion function matching criteria such as soft or hard conversion, source and destination types, and the conversion function.If a user is trying to remove a conversion function he registered, all parameters can be used. If he is trying to remove a library’s default conversion function, there is no guarantee the
nameandfuncparameters will match the user’s chosen values. Passing in some values may cause this function to fail. A good practice is to pass in NULL as their values.All parameters are optional. The missing parameters will be used to generalize the search criteria.
The conversion function pointer type declaration is described in
H5Tregister.- Parameters:
-
H5T_pers_t typeIN: Conversion function type:
H5T_PERS_HARDfor hard conversion functions or
H5T_PERS_SOFTfor soft conversion functions.const char * nameIN: Name displayed in diagnostic output. hid_t src_idIN: Identifier of source datatype. hid_t dst_idIN: Identifier of destination datatype. H5T_conv_t funcIN: Function to convert between source and destination datatypes. - Returns:
- Returns a non-negative value if successful;
otherwise returns a negative value.
- Fortran90 Interface:
- None.
- History:
Release C 1.6.3 The following change occurred in the H5Tconv_tfunction:
nelmtsparameter type changed to size_t.
- Last modified: 24 August 2012
- Name: H5Tvlen_create
- Signature:
- Name: H5Tvlen_create
- hid_t
H5Tvlen_create( hid_tbase_type_id) - Purpose:
- Creates a new variable-length array datatype.
- Description:
H5Tvlen_createcreates a new one-dimensional array datatype of variable-length (VL) with the base datatypebase_type_id.This one-dimensional array often represents a data sequence of the base datatype, such as characters for character sequences or vertex coordinates for polygon lists. The base type specified for the VL datatype can be any HDF5 datatype, including another VL datatype, a compound datatype, or an atomic datatype.
When necessary, use
H5Tget_superto determine the base type of the VL datatype.The datatype identifier returned from this function should be released with
H5Tcloseor resource leaks will result. Under certain circumstances,H5Dvlen_reclaimmust also be used.- Note:
H5Tvlen_createcannot be used to create a variable-length string datatype.H5Tvlen_createcalled with a string or character base type creates a variable-length sequence of strings (a variable-length, 1-dimensional array), with each element of the array being of the string or character base type.To create a variable-length string datatype, see “Creating variable-length string datatypes.”
- Parameters:
hid_t base_type_idIN: Base type of datatype to create. - Returns:
- Returns datatype identifier if successful;
otherwise returns a negative value.
- See Also:
H5Dvlen_get_buf_sizeH5Dvlen_reclaim- “Creating variable-length string datatypes”
- Fortran90 Interface: h5tvlen_create_f
-
SUBROUTINE h5tvlen_create_f(type_id, vltype_id, hdferr) IMPLICIT NONE INTEGER(HID_T), INTENT(IN) :: type_id ! Datatype identifier of base type ! Base type can only be atomic INTEGER(HID_T), INTENT(OUT) :: vltype_id ! VL datatype identifier INTEGER, INTENT(OUT) :: hdferr ! Error code END SUBROUTINE h5tvlen_create_f - History:
Release Change 1.4.5 Fortran subroutine introduced in this release.
The HDF Group Help Desk: 
Describes HDF5 Release 1.8.20, November 2017. |
Copyright by
The HDF Group
and the Board of Trustees of the University of Illinois |