linesearch.c File Reference

Detailed Description

Routines to perform exact or backtracking linesearch.

Author

Ben Hermans

Once the direction is found using the semismooth Newton method, the functions in this file can be called to calculate a stepsize, either using exact linesearch or a backtracking linesearch to satisfy the armijo condition.

Definition in file linesearch.c.

#include <qpalm/linesearch.h>
#include <qpalm/lin_alg.h>
#include <stdlib.h>

Include dependency graph for linesearch.c:

Go to the source code of this file.

Functions
c_float	exact_linesearch (QPALMWorkspace *work, solver_common *c)
	Execute exact linesearch (using qsort)
void	vec_array_copy (c_float *a, array_element *b, size_t n)
	Helper function to copy vector a in array b (with indices)
void	select_subsequence (const array_element *a, array_element *b, const c_int *L, size_t n)
	Select subsequence based on a set of indices, \(b = a(L)\).
c_float	vec_prod_ind (const c_float *a, const c_float *b, const c_int *L, size_t n)
	Inner product over index set, \(a(L)^T\cdot b(L)\).
int	compare (const void *a, const void *b)
	Helper function for qsort.

Function Documentation

exact_linesearch()

c_float exact_linesearch	(	QPALMWorkspace *	work,
		solver_common *	c
	)

Execute exact linesearch (using qsort)

Parameters

work	Workspace
c	Linear systems solver environment

Returns

tau Step size

Definition at line 14 of file linesearch.c.

Here is the call graph for this function:

Here is the caller graph for this function:

vec_array_copy()

void vec_array_copy	(	c_float *	a,
		array_element *	b,
		size_t	n
	)

Helper function to copy vector a in array b (with indices)

Parameters

a	Vector
b	Array (vector with added indices)
n	Vector length

Definition at line 122 of file linesearch.c.

Here is the caller graph for this function:

select_subsequence()

void select_subsequence	(	const array_element *	a,
		array_element *	b,
		const c_int *	L,
		size_t	n
	)

Select subsequence based on a set of indices, \(b = a(L)\).

Parameters

a	Input array
b	Outpur array
L	Index set
n	Length of a

Definition at line 134 of file linesearch.c.

Here is the caller graph for this function:

vec_prod_ind()

c_float vec_prod_ind	(	const c_float *	a,
		const c_float *	b,
		const c_int *	L,
		size_t	n
	)

Inner product over index set, \(a(L)^T\cdot b(L)\).

Parameters

a	Vector
b	Vector
L	Index set
n	Vector length

Definition at line 145 of file linesearch.c.

Here is the caller graph for this function:

compare()

int compare	(	const void *	a,
		const void *	b
	)

Helper function for qsort.

Carries out comparison between two array_elements

Parameters

a	Pointer to array element
b	Pointer to array element

Returns

a.x > b.x

Definition at line 158 of file linesearch.c.

Here is the caller graph for this function: