MFRotation mf;
mf.push_back(SFRotation(45.0f,0.0f,1.0f,0.0f));
mf.push_front(SFRotation(-45.0f,0.0f,1.0f,0.0f));
mf[0].setAngle(60.0f);
but since it uses STL principles, you have all useful concepts such as iterator, algorithms, etc...
Below is included the documentation for this field type from the ISO standard.
5.8 SFRotation and
MFRotation
The SFRotation field and event specifies one arbitrary
rotation. The MFRotation field and event specifies zero or more
arbitrary rotations. An SFRotation is written to the VRML file as
four ISO C floating point values (see 2.[ISOC]) separated by
whitespace. The first three values specify a normalized rotation axis
vector about which the rotation takes place. The fourth value
specifies the amount of right-handed rotation about that axis in
radians. For example, an SFRotation containing a PI radians
rotation about the Y axis is:
fooRot 0.0 1.0 0.0 3.14159265
The 3x3 matrix representation of a rotation (x y z a) is
[ tx2+c txy+sz txz-sy
txy-sz ty2+c tyz+sx
txz+sy tyz-sx tz2+c ]
where c = cos(a), s = sin(a), and t = 1-c
The initial value of an SFRotation eventOut is (0 0 1 0). The initial
value of an MFRotation eventOut is [ ].