Force single precision on lsqlin?

I am trying to create a series of splines with constrained data points on the ends of the splines. I am using the lsqlin function in the process of doing this and developed a working algorithm. I am now trying to change the data I am working with to single precision. This causes an error in the lsqlin function, however. Is there anyway to force lsqlin or any other similar function to use single precision?