function [c] = RigidTransform(A,b)
% There are two possibilities:
% 1) A is a translation vector and b is a rotation axis/angle vector or
% 2) A is a translation vector and b is a rotation matrix.
% No error checking: the user is responsible for this input.
% In both cases the output c is the corresponding homogeneous rigid body transform
if isvector(b)
b=RotFromVector(b);
end
c=zeros(4,4);
c(1:3,1:3)=b;
c(4,4)=1;
c(1:3,4)=[A(1);A(2);A(3)];
end