CStreamingVwFile Class Reference

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Detailed Description

Class StreamingVwFile to read vector-by-vector from Vowpal Wabbit data files. It reads the example and label into one object of VwExample type.

Definition at line 26 of file StreamingVwFile.h.

Inheritance diagram for CStreamingVwFile:

List of all members.

Public Member Functions
	CStreamingVwFile ()
	CStreamingVwFile (char *fname, char rw='r')
virtual	~CStreamingVwFile ()
void	set_parser_type (E_VW_PARSER_TYPE type=T_VW)
virtual void	get_vector (VwExample *&ex, int32_t &len)
virtual void	get_vector_and_label (VwExample *&ex, int32_t &len, float64_t &label)
void	set_env (CVwEnvironment *env_to_use)
CVwEnvironment *	get_env ()
void	set_write_to_cache (bool write_cache)
bool	get_write_to_cache ()
virtual bool	is_seekable ()
virtual const char *	get_name () const
Public Attributes
parse_func	parse_example
	The function which will be called for parsing.
Protected Attributes
CVwParser *	parser
	Parser for vw format.
E_VW_PARSER_TYPE	parser_type
	Parser type.
CVwEnvironment *	env
	Environment used for vw - used by parser.
bool	write_to_cache
	Write data to a binary cache file.

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Constructor & Destructor Documentation

CStreamingVwFile

(

)

Default constructor

Definition at line 15 of file StreamingVwFile.cpp.

CStreamingVwFile	(	char *	fname,
		char	rw = 'r'
	)

Constructor taking file name argument

Parameters:

	fname	file name
	rw	read/write mode

Definition at line 21 of file StreamingVwFile.cpp.

~CStreamingVwFile

(

)

[virtual]

Destructor

Definition at line 27 of file StreamingVwFile.cpp.

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Member Function Documentation

CVwEnvironment* get_env

(

)

Return the environment

Returns:

environment as CVwEnvironment*

Definition at line 94 of file StreamingVwFile.h.

virtual const char* get_name

(

)

const [virtual]

Returns:

object name

Reimplemented from CStreamingFile.

Definition at line 121 of file StreamingVwFile.h.

void get_vector	(	VwExample *&	ex,
		int32_t &	len
	)			[virtual]

Returns the parsed example.

The example contains the label if available, and also contains length of the feature vector. These parameters are redundant.

Parameters:

	ex	examples as VwExample*, set by reference
	len	length of vector, untouched

Reimplemented from CStreamingFile.

Definition at line 54 of file StreamingVwFile.cpp.

void get_vector_and_label	(	VwExample *&	ex,
		int32_t &	len,
		float64_t &	label
	)			[virtual]

Returns the parsed example.

TODO: Make this fail if examples are found to be unlabelled.

Parameters:

	ex	example as VwExample*, set by reference
	len	length of vector, untouched
	label	label, untouched

Reimplemented from CStreamingFile.

Definition at line 61 of file StreamingVwFile.cpp.

bool get_write_to_cache

(

)

Get whether cache will be written

Returns:

whether to write to cache

Definition at line 116 of file StreamingVwFile.h.

virtual bool is_seekable

(

)

[virtual]

Whether the stream is seekable/resettable

Returns:

false by default, unless overloaded

Reimplemented from CStreamingFile.

Definition at line 118 of file StreamingVwFile.h.

void set_env

(

CVwEnvironment *

env_to_use

)

Set environment for vw

Parameters:

env_to_use

CVwEnvironment* environment

Definition at line 84 of file StreamingVwFile.h.

void set_parser_type

(

E_VW_PARSER_TYPE

type = T_VW

)

Set the type of parser, i.e., T_VW, T_SVMLIGHT or T_DENSE.

Parameters:

type

parser type as enum

Definition at line 33 of file StreamingVwFile.cpp.

void set_write_to_cache

(

bool

write_cache

)

Set whether cache will be written

Parameters:

write_cache

whether to write to cache

Definition at line 105 of file StreamingVwFile.h.

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Member Data Documentation

CVwEnvironment* env [protected]

Environment used for vw - used by parser.

Definition at line 144 of file StreamingVwFile.h.

parse_func parse_example

The function which will be called for parsing.

Definition at line 128 of file StreamingVwFile.h.

CVwParser* parser [protected]

Parser for vw format.

Definition at line 138 of file StreamingVwFile.h.

E_VW_PARSER_TYPE parser_type [protected]

Parser type.

Definition at line 141 of file StreamingVwFile.h.

bool write_to_cache [protected]

Write data to a binary cache file.

Definition at line 147 of file StreamingVwFile.h.

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The documentation for this class was generated from the following files:

• StreamingVwFile.h
• StreamingVwFile.cpp