<s>
In	O
mathematics	O
,	O
a	O
Coons	B-Algorithm
patch	I-Algorithm
,	O
is	O
a	O
type	O
of	O
surface	O
patch	O
or	O
manifold	B-Architecture
parametrization	O
used	O
in	O
computer	O
graphics	O
to	O
smoothly	O
join	O
other	O
surfaces	O
together	O
,	O
and	O
in	O
computational	B-Algorithm
mechanics	I-Algorithm
applications	O
,	O
particularly	O
in	O
finite	B-Application
element	I-Application
method	I-Application
and	O
boundary	B-Algorithm
element	I-Algorithm
method	I-Algorithm
,	O
to	O
mesh	O
problem	O
domains	O
into	O
elements	O
.	O
</s>
<s>
Coons	B-Algorithm
patches	I-Algorithm
are	O
named	O
after	O
Steven	O
Anson	O
Coons	O
,	O
and	O
date	O
to	O
1967	O
.	O
</s>
<s>
Although	O
the	O
bilinear	O
Coons	B-Algorithm
patch	I-Algorithm
exactly	O
meets	O
its	O
four	O
boundary	O
curves	O
,	O
it	O
does	O
not	O
necessarily	O
have	O
the	O
same	O
tangent	O
plane	O
at	O
those	O
curves	O
as	O
the	O
surfaces	O
to	O
be	O
joined	O
,	O
leading	O
to	O
creases	O
in	O
the	O
joined	O
surface	O
along	O
those	O
curves	O
.	O
</s>
<s>
To	O
fix	O
this	O
problem	O
,	O
the	O
linear	O
interpolation	B-Algorithm
can	O
be	O
replaced	O
with	O
cubic	B-Algorithm
Hermite	I-Algorithm
splines	I-Algorithm
with	O
the	O
weights	O
chosen	O
to	O
match	O
the	O
partial	O
derivatives	O
at	O
the	O
corners	O
.	O
</s>
<s>
This	O
forms	O
a	O
bicubically	O
blended	O
Coons	B-Algorithm
patch	I-Algorithm
.	O
</s>
