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If I have a mesh that has been fitted using tricubic+bicubic bases and then I want to add a trilinear basis, the elements need to be updated.

Is there a command to do automatically copy the element definitions for the new basis  from an existing one?

e.g.::

	# basis 1=tricubic, basis 2=bicubic
	fem define bas;tricubic 
	
	# basis 3=trilinear
	fem define;add bas;trilinear
	
	fem define node;mymesh
	
	# this element file only contains element definitions for basis 1
	fem define elem;mymesh

At this point cm prompts for element definitions for basis 3.

If I change the order and do this::

	# basis 1=tricubic, basis 2=bicubic
	fem define bas;tricubic 
	
	fem define node;mymesh
	
	# this element file only contains element definitions for basis 1
	fem define elem;mymesh
	
	# basis 3=trilinear
	fem define;add bas;trilinear

then it doesn't prompt but the elements are undefined for basis 3. 


Is there a command to make it update the element definitions automatically for the new basis?



From karl Fri Jul 28 15:41:22 +1200 2006
From: karl
Date: Fri, 28 Jul 2006 15:41:22 +1200
Subject: when to define elements for a basis
Message-ID: <20060728154122+1200@www.cmiss.org>

IIRC, and if a basis is define;added after reading in the elements,
then the element definition for that basis is defined when it is used
in an .ipelfd element field file.

So the element is defined when the field (or geometry) that uses it is defined.

When where you planning to use basis 3?

The problem is that there is nowhere to specify the field information for the
dependant variable.  Some equation types have some questions in the .ipequa
file.  I wonder if this is because cm was written first for elasticity where
the dependant variable is the geometry (but I don't know what is done about a
pressure term if present).

For other equation types where the dependant variable field may be represented
quite differently, the approach seems to have been the following:

* When reading in the geometry, ask questions about every basis function,
  even if not used, because it may be used for a dependant variable later.

This requires any basis functions that may be used for a dependant variable to
be defined before reading in the geometry, and has led to the problem that
different .ipelem files are required for the same geometry if different
numbers of unused basis functions are defined.