File and Group¶

The following classes are all defined within namespace HIPP::IO.

Class H5File¶

class H5File¶

The API for HDF5 file.

H5File instance can be copy-constructed, copy-assigned, move-constructed and move-assigned. The copy, move operations and destructor are all noexcept. The copy operations are shallow-copy, i.e., instances of source and target refer to the same underlying file object (like a shared_ptr).

H5File(const string &name, const string &flag, const H5Proplist &cporp = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

Constructor - create a new file or open an existing file named name.

flag controls the the open/creation and Read/Write mode. It can be one of the following values

“w”	create a new file (truncate if existing) as R/W mode.
“r”	open an existing file as R mode.
“a”	open an existing file as R/W mode.
“ac” or “ca”	open an existing file (create if not existing) as R/W mode.

cprop and aprop specify the creation and access properties, respectively.

template<typename T> H5Dataset create_dataset(const string &name, const vector<hsize_t> &dims, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

H5Dataset create_dataset(const string &name, const H5Datatype &dtype, const vector<hsize_t> &dims, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

template<typename T> H5Dataset create_dataset_scalar(const string &name, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

H5Dataset create_dataset_str(const string &name, size_t len, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

Create a new dataset (or open an existing dataset) under the root group of the file instance.

name specifies the name of the dataset to open/create. If the dataset does not exist, it is created. Otherwise, if flag=="trunc", the dataset is opened, or if flag=="excl", an exception ErrH5 is thrown.

lcprop specifies the link-creation properties, cprop specifies the dataset creation properties, and aprop specifies the dataset access properties.

Four methods are:

create_dataset<T>() creates an array-like dataset with element type T, array shape dims. Type T can be either numeric Predefined Datatypes (e.g., int, float), or std::string. For the numeric types, dims is the array shape. For std::string, dims must be { num_of_str, max_str_size}, where max_str_size must contain the space of the terminate null character, i.e., this dataset allows storage for an 1-d array of C strings. It is best to calculate dims use H5TypeStr::shape()
create_dataset() creates and array-like dataset with element type dtype, array shape dims.
create_dataset_scalar() creates a scalar dataset.
create_dataset_str() creates a dataset for a single string.

H5Dataset open_dataset(const string &name, const H5Proplist &aprop = H5Proplist::defaultval)¶

bool dataset_exists(const string &name) const¶

open_dataset(name) opens an existing dataset named name. If not existing, throw an exception ErrH5.

To check whether a dataset exists, use dataset_exists(name).

template<typename T> H5Attr create_attr(const string &name, const vector<hsize_t> &dims, const string &flag = "trunc")¶

H5Attr create_attr(const string &name, const H5Datatype &dtype, const vector<hsize_t> &dims, const string &flag = "trunc")¶

template<typename T> H5Attr create_attr_scalar(const string &name, const string &flag = "trunc")¶

H5Attr create_attr_str(const string &name, size_t len, const string &flag = "trunc")¶

Create a new attribute (or open an existing attribute) under the root group of this file instance.

The template parameter and argument list is the same with create_dataset() and its variants. The difference is that you cannot specify any property list.

H5Attr open_attr(const string &name)¶

bool attr_exists(const string &name) const¶

open_attr(name) opens an existing attribute named name. If not existing, throw an exception ErrH5.

To check whether an attribute exists, use attr_exists(name).

H5Group create_group(const string &name)¶

H5Group try_create_group(const string &name)¶

H5Group open_group(const string &name)¶

bool group_exists(const string &name) const¶

Data group manipulation methods.

create_group(name) creates a group named name. If it has already existed, throw an exception ErrH5.

try_create_group(name) is similar, but open the group if it has already existed.

open_group(name) opens an existing group. If it is not existed, throw an exception ErrH5.

group_exists(name) check whether a group exists.

static H5Proplist create_proplist(const string &cls = "c")¶

Create a file-related property list of given class cls. Possible values are:

“c” or “create”	properties for file creation
“a” or “access”	properties for file access
“m” or “mount”	properties for file mounting

Class H5Group¶

class H5Group¶

template<typename T> H5Dataset create_dataset(const string &name, const vector<hsize_t> &dims, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

H5Dataset create_dataset(const string &name, const H5Datatype &dtype, const vector<hsize_t> &dims, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

template<typename T> H5Dataset create_dataset_scalar(const string &name, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

H5Dataset create_dataset_str(const string &name, size_t len, const string &flag = "trunc", const H5Proplist &lcprop = H5Proplist::defaultval, const H5Proplist &cprop = H5Proplist::defaultval, const H5Proplist &aprop = H5Proplist::defaultval)¶

Create a new dataset (or open an existing dataset) under the current group instance.

These methods have the same template parameter and argument list as H5File::create_dataset() and its variants. See there for the details.

H5Dataset open_dataset(const string &name, const H5Proplist &aprop = H5Proplist::defaultval)¶

bool dataset_exists(const string &name) const¶

open_dataset(name) opens an existing dataset named name. If not existing, throw an exception ErrH5.

To check whether a dataset exists, use dataset_exists(name).

template<typename T> H5Attr create_attr(const string &name, const vector<hsize_t> &dims, const string &flag = "trunc")¶

H5Attr create_attr(const string &name, const H5Datatype &dtype, const vector<hsize_t> &dims, const string &flag = "trunc")¶

template<typename T> H5Attr create_attr_scalar(const string &name, const string &flag = "trunc")¶

H5Attr create_attr_str(const string &name, size_t len, const string &flag = "trunc")¶

Create a new attribute (or open an existing attribute) under the current group.

The template parameter and argument list are the same with H5File::create_dataset() and its variants. The difference is that you cannot specify any property list.

H5Attr open_attr(const string &name)¶

bool attr_exists(const string &name) const¶

Opens an existing attribute of name name. If not existing, throw an error ErrH5.

attr_exists() checks whether an attribute has been existed.

H5Group create_group(const string &name)¶

H5Group try_create_group(const string &name)¶

H5Group open_group(const string &name)¶

bool group_exists(const string &name) const¶

Data group manipulation methods.

create_group(name) creates a group named name. If it has already existed, throw an exception ErrH5.

try_create_group(name) is similar, but open the group if it has already existed.

open_group(name) opens an existing group. If it is not existed, throw an exception ErrH5.

group_exists(name) check whether a group exists.