opatIO.h File Reference

Header file for the OPAT I/O library, providing structures and functions for reading and manipulating OPAT files. More...

#include <fstream>
#include <memory>
#include <string>
#include <sys/types.h>
#include <vector>
#include <utility>
#include <cstdint>
#include <unordered_map>
#include <limits>
#include "indexVector.h"

Go to the source code of this file.

Classes
struct	opat::Header
	Structure to hold the header information of an OPAT file. More...
struct	opat::CardHeader
	Structure to hold the header information of a DataCard in an OPAT file. More...
struct	opat::CardCatalogEntry
	Structure to hold the index information of a table in an OPAT file. More...
struct	opat::CardCatalog
	Structure to hold the catalog of tables in a DataCard. More...
struct	opat::TableIndexEntry
	Structure to hold the index information of a table within a DataCard. More...
struct	opat::TableIndex
	Structure to hold the index of tables within a DataCard. More...
struct	opat::Slice
	Structure to represent a slice of data. More...
struct	opat::OPATTable
	Structure to hold the data of an OPAT table. More...
struct	opat::DataCard
	Structure to hold a DataCard, which contains multiple tables. More...
struct	opat::Bounds
	Structure to hold the minimum and maximum values for a dimension. More...
struct	opat::OPAT
	Structure to hold the entire OPAT file. More...

Namespaces
namespace	opat

Functions
OPAT	opat::readOPAT (const std::string &filename)
	Reads an OPAT file and returns its contents as an OPAT structure.
Header	opat::readHeader (std::ifstream &file)
	Reads the header of an OPAT file.
CardCatalogEntry	opat::readCardCatalogEntry (std::ifstream &file, uint64_t offset, uint16_t numIndex, uint8_t hashPrecision)
	Reads a CardCatalogEntry from the file.
CardCatalog	opat::readCardCatalog (std::ifstream &file, const Header &header)
	Reads the CardCatalog from the file.
std::unordered_map< FloatIndexVector, DataCard >	opat::readDataCards (std::ifstream &file, const Header &header, const CardCatalog &cardCatalog)
	Reads all DataCards from the file.
DataCard	opat::readDataCard (std::ifstream &file, const CardCatalogEntry &entry)
	Reads a single DataCard from the file.
CardHeader	opat::readDataCardHeader (std::ifstream &file, const CardCatalogEntry &entry)
	Reads the header of a DataCard from the file.
TableIndex	opat::readTableIndex (std::ifstream &file, const CardCatalogEntry &entry, const CardHeader &header)
	Reads the TableIndex from a DataCard.
OPATTable	opat::readOPATTable (std::ifstream &file, const CardCatalogEntry &cardEntry, const TableIndexEntry &tableEntry)
	Reads an OPATTable from the file.
bool	opat::hasMagic (const std::string &filename)
	Checks if a file has the correct magic number for an OPAT file.
bool	opat::is_big_endian ()
	Determines if the system is big-endian.
template<typename T>
T	opat::swap_bytes (T value)
	Swaps the byte order of a value.

Detailed Description

Header file for the OPAT I/O library, providing structures and functions for reading and manipulating OPAT files.

This file defines the core data structures and functions used for handling OPAT files in C++. The OPAT format is designed for efficient storage and retrieval of multidimensional data tables, with metadata and indexing for fast access.

The design prioritizes:

• Compactness: Structures are packed to minimize memory usage.
• Flexibility: Support for multiple tables and metadata.
• Performance: Use of unordered maps for fast lookups.

Example:

#include "opatIO.h"
 
int main() {
    std::string filename = "example.opat";
    opat::OPAT file = opat::readOPAT(filename);
    const auto& table = file.get({1.0, 2.0, 3.0}).get("table_tag");
    table.print();
    return 0;
}