<s>
In	O
optimization	O
,	O
the	O
line	B-Algorithm
search	I-Algorithm
strategy	O
is	O
one	O
of	O
two	O
basic	O
iterative	B-Algorithm
approaches	O
to	O
find	O
a	O
local	O
minimum	O
of	O
an	O
objective	O
function	O
.	O
</s>
<s>
The	O
other	O
approach	O
is	O
trust	B-Algorithm
region	I-Algorithm
.	O
</s>
<s>
The	O
line	B-Algorithm
search	I-Algorithm
approach	O
first	O
finds	O
a	O
descent	O
direction	O
along	O
which	O
the	O
objective	O
function	O
will	O
be	O
reduced	O
and	O
then	O
computes	O
a	O
step	B-General_Concept
size	I-General_Concept
that	O
determines	O
how	O
far	O
should	O
move	O
along	O
that	O
direction	O
.	O
</s>
<s>
The	O
descent	O
direction	O
can	O
be	O
computed	O
by	O
various	O
methods	O
,	O
such	O
as	O
gradient	B-Algorithm
descent	I-Algorithm
or	O
quasi-Newton	B-Algorithm
method	I-Algorithm
.	O
</s>
<s>
The	O
step	B-General_Concept
size	I-General_Concept
can	O
be	O
determined	O
either	O
exactly	O
or	O
inexactly	O
.	O
</s>
<s>
Here	O
is	O
an	O
example	O
gradient	O
method	O
that	O
uses	O
a	O
line	B-Algorithm
search	I-Algorithm
in	O
step	O
4	O
.	O
</s>
<s>
At	O
the	O
line	B-Algorithm
search	I-Algorithm
step	O
(	O
4	O
)	O
the	O
algorithm	O
might	O
either	O
exactly	O
minimize	O
h	O
,	O
by	O
solving	O
,	O
or	O
loosely	O
,	O
by	O
asking	O
for	O
a	O
sufficient	O
decrease	O
in	O
h	O
.	O
One	O
example	O
of	O
the	O
former	O
is	O
conjugate	B-Algorithm
gradient	I-Algorithm
method	I-Algorithm
.	O
</s>
<s>
The	O
latter	O
is	O
called	O
inexact	O
line	B-Algorithm
search	I-Algorithm
and	O
may	O
be	O
performed	O
in	O
a	O
number	O
of	O
ways	O
,	O
such	O
as	O
a	O
backtracking	B-Algorithm
line	I-Algorithm
search	I-Algorithm
or	O
using	O
the	O
Wolfe	O
conditions	O
.	O
</s>
<s>
Like	O
other	O
optimization	O
methods	O
,	O
line	B-Algorithm
search	I-Algorithm
may	O
be	O
combined	O
with	O
simulated	B-Algorithm
annealing	I-Algorithm
to	O
allow	O
it	O
to	O
jump	O
over	O
some	O
local	O
minima	O
.	O
</s>
<s>
Of	O
the	O
various	O
methods	O
of	O
dividing	O
the	O
interval	O
,	O
golden	B-Algorithm
section	I-Algorithm
search	I-Algorithm
is	O
particularly	O
simple	O
and	O
effective	O
,	O
as	O
the	O
interval	O
proportions	O
are	O
preserved	O
regardless	O
of	O
how	O
the	O
search	O
proceeds	O
:	O
</s>
