basis2d

(./FEM/basis2d.m)

Function Synopsis

[phi,jj]=basis2d(fem_grid_struct,xylist,j)

Help text

BASIS2D compute basis functions for input points in FEM grid
   BASIS2D computes the FEM basis functions for a given 
   horizontal position, specified either in the argument
   list or with the mouse.

   In determining which element has been selected, 
   BASIS2D needs elemental areas and shape functions.
   Element areas are returned by LOADGRID.
   The routine BELINT computes shape function information
   and attaches it to the input fem_grid_struct.
   These two functions MUST be run before BASIS2D will 
   run.

   BELINT is run as: 
      new_struct=belint(fem_grid_struct); 
   If ever needed, EL_AREAS is run as:
      [new_struct,ineg]=el_areas(fem_grid_struct); 

   INPUT : fem_grid_struct - (from LOADGRID, see FEM_GRID_STRUCT)     
           xylist  (op)    - points to find elements for [n x 2 double] 
           j       (op)    - element list corresponding to the xylist
                             set of points.  Optional, but isf passed in, 
                             points will not be relocated. length(j) must
                             equal length(xylist).
           
   OUTPUT : basis function(s) and element number(s)
            If elements were NOT passed in, then providing two output
            arguments will collect the elements determined to contain the 
            specified points.
 
   CALL : >> [phi,j]=basis2d(fem_grid_struct)   for interactive
    or
          >> [phi,j]=basis2d(fem_grid_struct,xylist)        
    or
          >> phi=basis2d(fem_grid_struct,xylist,j)        

 Written by : Brian O. Blanton 
 Summer 1998

Cross-Reference Information

findelem       ./FEM/findelem.m
is_valid_struct./FEM/is_valid_struct.m
is_valid_struct2./FEM/is_valid_struct2.m