bipolyplot


Untitled

Plots a bipolynomial

Syntax

bipolyplot(B)
bipolyploy(B,P)
h = bipolyplot(…)

Description

bipolyplot(B) plots the bipolynomial represented by the matrix B over the domain .
bipolyplot(B,P) plots the bipolynomial B over the domain specified by the polyshape object P (see help polyshape for details).
h = bipolyplot( … ) returns a column vector of patch properties. Use h to modify properties of a specific bipolynomial plot after it is created.

Examples

Example − Visualization of finite element element shape functions
The bipolyplot function provides a convenient way to visualize finite element shape functions. For example, consider the “standard” nodal finite element shape functions for linear quadrilateral and triangular elements
over the “master” elements and defined as
,
respectively. As demonstrated in Example 1 of the bipolyder function documentation, the quadrilateral shape functions take the bipoly form
Q1 = 1/4*[1 -1; -1 1]; Q2 = 1/4*[-1 -1; 1 1]; Q3 = 1/4*[1 1; 1 1]; Q4 = 1/4*[-1 1;-1 1];
while the triangular shape functions take the form
T1 = -1/2*[0 1; 1 0 ]; T2 = 1/2*[ 0 0; 1 1]; T3 = 1/2*[0 1; 0 1];
Using the bipolyplot function, the quadrilateral shape functions can be easily plotted by
figure; bipolyplot(Q1);
figure; bipolyplot(Q2);
figure; bipolyplot(Q3);
figure; bipolyplot(Q4);
where it can be noted that shape function is equal to 1 at node i and zero at all other nodes.
Plots of the triangluar shape functions require the domain to be defined as polyshape object (note that the domain of the quadrilateral master element is equal to the default domain of the bipolyplot function), which can be defined as
P = polyshape([-1 1 -1],[-1 -1 1]);
By specifying this as the second argument in the bipolyplot function, along with the triangular shape functions, we get
figure; bipolyplot(T1,P);
figure; bipolyplot(T2,P);
figure; bipolyplot(T3,P);
where again the nodal property described above for the quadrilateral can be observed.

This function is part of……..