Utilities

Defined in pigo.hpp

enum pigo::FileType

Contains the supported file types.

Values:

enumerator MATRIX_MARKET

An edge list with size, typically .mtx files

enumerator EDGE_LIST

A file where each line is an edge. This is the simplest format PIGO supports. Each line is src dst if it is unweighted, or src dst weight if weighted.

enumerator PIGO_COO_BIN

A binary format storing a PIGO COO

enumerator PIGO_CSR_BIN

A binary format storing a PIGO CSR

enumerator PIGO_DIGRAPH_BIN

A binary format storing a PIGO DiGraph

enumerator PIGO_TENSOR_BIN

A binary format storing a Tensor CSR

enumerator GRAPH

A file with a head and where each line contains an adjacency list

enumerator AUTO

A special format where PIGO will try to detect the input

enum pigo::OpenMode

The support PIGO file opening modes.

READ indicates read-only, whereas WRITE indicates read and write, but on opening will create a new file (removing any old file.)

Values:

enumerator READ

Indicates a read-only file

enumerator WRITE

Indicates a writeable file, existing files will be removed

class pigo::FileReader

Performs actions on an opened PIGO file.

Public Functions

inline FileReader(FilePos d, FilePos end)

Initialize a new FileReader.

Parameters

• d – the current position of the reader

• end – one beyond the last valid position

inline void skip_comments()

Move the reader pass any comment lines.

template<typename T>
inline T read_int()

Read an integer from the file.

Note: this reads integers in base 10 only

Returns

the newly read integer

template<typename T>
inline T read_fp()

Read a floating point value from the file.

Returns

the newly read floating point

template<typename T>
inline T read_sign()

Read the sign value from an integer.

Reads out either + or -, as appropriate, from the given file position. The file position is the incremented.

Template Parameters

T – the type of the integer sign to return

Returns

a T value of either 1 or -1 as appropriate

inline bool at_end_of_line()

Determine if only spaces remain before the line.

Note that this does not increment the current position.

Returns

true if there are only spaces, false otherwise

inline void move_to_non_int()

Move the reader to the next non-int.

inline void move_to_non_fp()

Move the reader to the next non-floating point.

inline void move_to_fp()

Move the reader to the next floating point.

inline void move_to_first_int()

Move to the first integer.

This will move to the first found integer. If it is already on an integer, it will not move.

inline void move_to_next_int()

Move to the next integer.

Note: this will move through the current integer and then through any non-integer character to get to the next integer

inline void move_to_next_signed_int()

Move to the next signed integer.

Note: this will move through the current integer and then through any non-integer character to get to the next integer

These integers are signed and so can start with + or -

inline size_t count_spaces_to_eol()

Count the spaces in the line, moving the cursor.

inline void move_to_next_int_or_nl()

Move to the next integer or newline.

Note: this will move through the current integer or newline and then through any other character to get to the next integer or newline

inline void move_to_eol()

Move to the end of the current line.

This moves through the line and finishes on the newline character itself.

inline FileReader operator+(size_t s)

Increment the file reader by a count.

inline FileReader &operator+=(size_t s)

Increment the file reader by a count.

inline void smaller_end(FileReader &rhs)

Set an additional, smaller end.

This will either set a new end, if it is smaller than the current, or do nothing.

Parameters

new_end – the new end to consider

inline bool good()

Return if the reader is able to read.

Returns

true if there are values to read, false otherwise

inline size_t size()

Return the remaining size to be read.

Returns

the number of bytes remaining

inline bool at_str(std::string s)

Check whether the reader is at the string.

Parameters

s – the string to check against

Returns

true if the string matches, false otherwise

inline char peek()

Return the current character of the reader.

Returns

character the reader is at

inline bool at_nl_or_eol()

Return whether the reader is at a newline or EOL.

Returns

true if the reader is at the end of a line, false otherwise

inline bool at_zero()

Return whether the reader is at a ‘0’ integer.

Returns

true if the reader is at a ‘0’ integer

Public Members

FilePos d

Keep track of the current position

class pigo::File

Manages a file opened for parallel access.

Subclassed by pigo::ROFile, pigo::WFile

Public Functions

inline File(std::string fn, OpenMode mode, size_t max_size = 0)

Opens the given file.

Parameters

• fn – the file name to open

• mode – the mode to open the file in (READ, WRITE)

• max_size – (only used when mode=WRITE) the maximum size to allocate for the file

inline ~File() noexcept

Closes the open file and removes related memory.

File(const File&) = delete

Copying File is unavailable.

File &operator=(const File&) = delete

Copying File is unavailable.

inline File(File &&o)

Move constructor.

inline File &operator=(File &&o)

Move operator.

inline FilePos fp()

Return the current file position object.

inline void seek(size_t pos)

Seek to the specified offset in the file.

Parameters

pos – the position to seek to

template<class T>
inline T read()

Read the next value from the file.

Template Parameters

T – the type of object to read

Returns

the resulting object

inline void read(const std::string &s)

Read passed the given string.

This will ensure that the string exists in the file and then read passed it. The file position will be at the first character after the string when it is done. An error will be throw if the string does not match.

Parameters

s – the string to compare and read

template<class T>
inline void write(T val)

Write the given value to the file.

Template Parameters

T – the type of object to write

Parameters

val – the value to write

Returns

the resulting object

inline void parallel_write(char *v, size_t v_size)

Write a binary region in parallel.

Parameters

• v – the region of data to write

• v_size – the size of the region of data to write

inline void parallel_read(char *v, size_t v_size)

Read a binary region in parallel.

Parameters

• v – the region of data to save to

• v_size – the size of the region of data to read

inline size_t size()

Return the size of the file.

inline FileType guess_file_type()

Auto-detect the file type.

This will determine the file type based on a mixture of the extension, the contents of the file, and investigating the structure of the lines.

Note that this is a best-guess.

Returns

the determined FileType

inline FileReader reader()

Return a FileReader for this file.

Returns

returns a new FileReader object for this file

class pigo::ROFile : public pigo::File

Opens a read-only file for use in PIGO.

Public Functions

inline ROFile(std::string fn)

Opens the given file.

Parameters

fn – the file name to open

class pigo::WFile : public pigo::File

Opens a writeable file for use in PIGO.

Public Functions

inline WFile(std::string fn, size_t max_size)

Opens the given file.

Parameters

• fn – the file name to open

• max_size – the size to allocate for the file

typedef const char *pigo::FilePos

Keep track of the state of an open file.

typedef char *pigo::WFilePos

Keep track of the state of an open writeable file.

template<class T>
inline T pigo::read(FilePos &fp)

Read a binary value from an open file.

Reads a binary value out from the given file position. The file position object is incremented to just passed the value read out.

Template Parameters

T – the type of object to read

Parameters

fp – [inout] the file position object of the open file

Returns

the value read out

template<class T>
inline void pigo::write(FilePos &fp, T val)

Write a binary value from an open file.

Writes a binary value into a file at the given position. The file position object is incremented appropriately.

Template Parameters

T – the type of object to write

Parameters

• fp – [inout] the file position object of the open file

• val – the value to write to the file

inline void pigo::parallel_read(FilePos &fp, char *v, size_t v_size)

Read a binary region in parallel.

Parameters

• fp – the FilePos to begin writing at. This will be incremented passed the read region

• v – the region of data to save to

• v_size – the size of the region of data to read

inline void pigo::parallel_write(FilePos &fp, char *v, size_t v_size)

Write a binary region in parallel.

Parameters

• fp – the FilePos to begin writing at. This will be incremented passed the written block

• v – the region of data to write

• v_size – the size of the region of data to write

class Error : public std::runtime_error

Thrown by errors detected in PIGO.

Subclassed by pigo::NotYetImplemented

class NotYetImplemented : public pigo::Error

Thrown when something is not implemented yet.