FitPoly returning wrong function for some overdetermined systems
The FitPoly command is occasionally returning incorrect functions when provided with points fitting a lower degree curve.
should return -x, but returns x.
returns the correct value -x.
Other examples include
This seems to be an issue when the leading coefficient is -1 and the degree is one higher than necessary; the leading coefficient is missing its -1 sign term.
returns x^2+2x+1 instead of -x^2+2x+1.