COMSOL Multiphysics™

femwave
Weak coefficients are cell arrays of length n. They become cell arrays of length 2n,
by moving the existing entries down to the second half, then replacing all references
therein to u_test, ux_test, etc. with references to v_test, vx_test, etc. The first
half of the vector contains n entries of the form v i *u i _test.
Dweak coefficients are cell arrays of length n. They become cell arrays of length 2n,
by moving the existing entries down to the second half, then replacing all references
therein to u_time, ux_time, u_test, ux_test, etc. with references to v_time,
vx_time, v_test, vx_test, etc. The first half of the vector contains n entries of the
form u i _time*u i _test.
Constr coefficients are cell arrays of length n. They become cell arrays of length 2n,
by moving the existing entries down to the second half. If Tdiff is on, then the top
half of the vector is filled by the following entries. If one of the coefficients is c i , one
of the new entries in the top half of the new vector is
where ( v j
)
xk
represents the partial derivative of v j
with respect to space coordinate
x k
, and where there is implicit summation over repeated indices.
The function femwave accepts the following property/value pairs:
TABLE 1-42: VALID PROPERTY/VALUE PAIRS
PROPERTY VALUES DEFAULT DESCRIPTION
Defaults off | on off Return default fields
Diff
cell array with strings
that may contain the
strings r, var and/or
expr or the strings
off or on
∂c i
∂c i
∂c i
+ v
∂t j
+ ( v
∂ uj j
)
xk
∂( u j
)
xk
on (for
general form)
Differentiate constraints.
Describes which fields
that are differentiated if
Tdiff is on. See also
femdiff.
Geomnum integer 1 Geometry number
Shrink off | on off Shrinks coefficients to
most compact form.
Simplify off | on on Simplify differentiated
expressions
Tdiff on | off on Differentiate constraints
with respect to time
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