findelem

(./FEM/findelem.m)

Function Synopsis

j=findelem(fem_grid_struct,xylist)

Help text

FINDELEM element finding utility
   FINDELEM finds the element number for the
   current mouse position.  FINDELEM prompts
   the user to click on the current axes and returns
   the element for the "click-on" position, or NaN
   if the click is outside the domain.

   Alternatively, a list of horizontal points can
   be passed in and a list of element numbers, one for
   each input point, will be returned; NaN is returned
   for each point outside of the FEM domain.

   In determining which element has been selected,
   FINDELEM needs elemental areas and shape functions.
   The routines BELINT and EL_AREAS compute these arrays
   and add them to a previously created fem_grid_struct.
   These two functions MUST be run before FINDELEM will
   run.
   	  BELINT is run as:
   		 new_struct=belint(fem_grid_struct);
   	  EL_AREAS is run as:
   		 [new_struct,ineg]=el_areas(fem_grid_struct);

   INPUT : fem_grid_struct - (from LOADGRID, see FEM_GRID_STRUCT)
   	    xylist	    - points to find elements for [n x 2 double]

   OUTPUT : an element number(s)
 
   CALL : >> j=findelem(fem_grid_struct)   for interactive
     OR   >> j=findelem(fem_grid_struct,xylist)        

   Written by : Brian O. Blanton 
   Summer 1997

Cross-Reference Information

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

basis2d        ./FEM/basis2d.m
showelem       ./FEM/showelem.m