Lagrange.h¶
Note
The documentation on this page was automatically extracted from the DOLFIN C++ code and may need to be edited or expanded.
-
class
Lagrange
¶ Parent class(es)
Lagrange polynomial (basis) with given degree q determined by n = q + 1 nodal points.
Example: q = 1 (n = 2)
Lagrange p(1); p.set(0, 0.0); p.set(1, 1.0);It is the callers responsibility that the points are distinct.
This creates a Lagrange polynomial (actually two Lagrange polynomials):
p(0,x) = 1 - x (one at x = 0, zero at x = 1) p(1,x) = x (zero at x = 0, one at x = 1)-
Lagrange
(std::size_t q)¶ Constructor
-
void
set
(std::size_t i, double x)¶ Specify point
-
std::size_t
size
() const¶ Return number of points
-
std::size_t
degree
() const¶ Return degree
-
double
point
(std::size_t i) const¶ Return point
-
double
operator()
(std::size_t i, double x)¶ Return value of polynomial i at given point x
-
double
eval
(std::size_t i, double x)¶ Return value of polynomial i at given point x
-
double
ddx
(std::size_t i, double x)¶ Return derivate of polynomial i at given point x
-
double
dqdx
(std::size_t i)¶ Return derivative q (a constant) of polynomial
-
std::string
str
(bool verbose) const¶ Return informal string representation (pretty-print)
-