material properties; this line is repeated numat times
example:

(a)      (b)      (c)    (d)         (e)
1000.0  1000.0  20000.0  1.0      0.0  0.0
2000.0  2000.0      0.0  0.0      0.0  0.0

(a) mu -- elastic rigidity modulus
(b) lambda -- second Lame elastic modulus
(c) viscosity coefficient -- set to zero for pure elastic behavior
(d) viscosity exponent -- set to 1 for linear Newtonian case
(e) body force (gravity) -- there are ndof numbers; these give the 1-, 2- or 3-dimensional body force to apply to elements in this group