"nan" returned for the angle when callin SE3.angvec()

[scottnortman]

When calling angvec() on the SE3 object with the below values:

dTx:

1 3.881e-14 0 -1.985e-13
-3.881e-14 1 1.438e-11 1.192e-13 0 -1.438e-11 1 0
0 0 0 1

I am getting a returned value of

ang:nan