logmath_t Struct Reference

Integer log math computation class. More...

#include <pocketsphinx/logmath.h>

Public Member Functions
POCKETSPHINX_EXPORT logmath_t *	logmath_init (float64 base, int shift, int use_table)
POCKETSPHINX_EXPORT logmath_t *	logmath_read (const char *filename)
POCKETSPHINX_EXPORT int32	logmath_write (logmath_t *lmath, const char *filename)
POCKETSPHINX_EXPORT int32	logmath_get_table_shape (logmath_t *lmath, uint32 *out_size, uint32 *out_width, uint32 *out_shift)
POCKETSPHINX_EXPORT float64	logmath_get_base (logmath_t *lmath)
POCKETSPHINX_EXPORT int	logmath_get_zero (logmath_t *lmath)
POCKETSPHINX_EXPORT int	logmath_get_width (logmath_t *lmath)
POCKETSPHINX_EXPORT int	logmath_get_shift (logmath_t *lmath)
POCKETSPHINX_EXPORT logmath_t *	logmath_retain (logmath_t *lmath)
POCKETSPHINX_EXPORT int	logmath_free (logmath_t *lmath)
POCKETSPHINX_EXPORT int	logmath_add_exact (logmath_t *lmath, int logb_p, int logb_q)
POCKETSPHINX_EXPORT int	logmath_add (logmath_t *lmath, int logb_p, int logb_q)
POCKETSPHINX_EXPORT int	logmath_log (logmath_t *lmath, float64 p)
POCKETSPHINX_EXPORT float64	logmath_exp (logmath_t *lmath, int logb_p)
POCKETSPHINX_EXPORT int	logmath_ln_to_log (logmath_t *lmath, float64 log_p)
POCKETSPHINX_EXPORT float64	logmath_log_to_ln (logmath_t *lmath, int logb_p)
POCKETSPHINX_EXPORT int	logmath_log10_to_log (logmath_t *lmath, float64 log_p)
POCKETSPHINX_EXPORT float	logmath_log10_to_log_float (logmath_t *lmath, float64 log_p)
POCKETSPHINX_EXPORT float64	logmath_log_to_log10 (logmath_t *lmath, int logb_p)
POCKETSPHINX_EXPORT float64	logmath_log_float_to_log10 (logmath_t *lmath, float log_p)

Detailed Description

Integer log math computation class.

Member Function Documentation

logmath_init()

POCKETSPHINX_EXPORT logmath_t * logmath_init	(	float64	base,
		int	shift,
		int	use_table
	)

Initialize a log math computation table.

Parameters

base	The base B in which computation is to be done.
shift	Log values are shifted right by this many bits.
use_table	Whether to use an add table or not

Returns

The newly created log math table.

logmath_read()

POCKETSPHINX_EXPORT logmath_t * logmath_read

(

const char *

filename

)

Memory-map (or read) a log table from a file.

logmath_write()

POCKETSPHINX_EXPORT int32 logmath_write	(	logmath_t *	lmath,
		const char *	filename
	)

Write a log table to a file.

logmath_get_table_shape()

POCKETSPHINX_EXPORT int32 logmath_get_table_shape	(	logmath_t *	lmath,
		uint32 *	out_size,
		uint32 *	out_width,
		uint32 *	out_shift
	)

Get the log table size and dimensions.

logmath_get_base()

POCKETSPHINX_EXPORT float64 logmath_get_base

(

logmath_t *

lmath

)

Get the log base.

logmath_get_zero()

POCKETSPHINX_EXPORT int logmath_get_zero

(

logmath_t *

lmath

)

Get the smallest possible value represented in this base.

logmath_get_width()

POCKETSPHINX_EXPORT int logmath_get_width

(

logmath_t *

lmath

)

Get the width of the values in a log table.

logmath_get_shift()

POCKETSPHINX_EXPORT int logmath_get_shift

(

logmath_t *

lmath

)

Get the shift of the values in a log table.

logmath_retain()

POCKETSPHINX_EXPORT logmath_t * logmath_retain

(

logmath_t *

lmath

)

Retain ownership of a log table.

Returns

pointer to retained log table.

logmath_free()

POCKETSPHINX_EXPORT int logmath_free

(

logmath_t *

lmath

)

Free a log table.

Returns

new reference count (0 if freed completely)

logmath_add_exact()

POCKETSPHINX_EXPORT int logmath_add_exact	(	logmath_t *	lmath,
		int	logb_p,
		int	logb_q
	)

Add two values in log space exactly and slowly (without using add table).

logmath_add()

POCKETSPHINX_EXPORT int logmath_add	(	logmath_t *	lmath,
		int	logb_p,
		int	logb_q
	)

Add two values in log space (i.e. return log(exp(p)+exp(q)))

logmath_log()

POCKETSPHINX_EXPORT int logmath_log	(	logmath_t *	lmath,
		float64	p
	)

Convert linear floating point number to integer log in base B.

logmath_exp()

POCKETSPHINX_EXPORT float64 logmath_exp	(	logmath_t *	lmath,
		int	logb_p
	)

Convert integer log in base B to linear floating point.

logmath_ln_to_log()

POCKETSPHINX_EXPORT int logmath_ln_to_log	(	logmath_t *	lmath,
		float64	log_p
	)

Convert natural log (in floating point) to integer log in base B.

logmath_log_to_ln()

POCKETSPHINX_EXPORT float64 logmath_log_to_ln	(	logmath_t *	lmath,
		int	logb_p
	)

Convert integer log in base B to natural log (in floating point).

logmath_log10_to_log()

POCKETSPHINX_EXPORT int logmath_log10_to_log	(	logmath_t *	lmath,
		float64	log_p
	)

Convert base 10 log (in floating point) to integer log in base B.

logmath_log10_to_log_float()

POCKETSPHINX_EXPORT float logmath_log10_to_log_float	(	logmath_t *	lmath,
		float64	log_p
	)

Convert base 10 log (in floating point) to float log in base B.

logmath_log_to_log10()

POCKETSPHINX_EXPORT float64 logmath_log_to_log10	(	logmath_t *	lmath,
		int	logb_p
	)

Convert integer log in base B to base 10 log (in floating point).

logmath_log_float_to_log10()

POCKETSPHINX_EXPORT float64 logmath_log_float_to_log10	(	logmath_t *	lmath,
		float	log_p
	)

Convert float log in base B to base 10 log.

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The documentation for this struct was generated from the following file:

• pocketsphinx/logmath.h