I am trying to constrain the coefficients on a higher order polynomial (let's say an order 6) for the curve to be decreasing.
I have found this link, where the fitting of a 3rd order polynomial is being fit, but that will not fit my data unfortunately.
Am I right in assuming that it is technically impossible to constraint a higher order polynomial? This would mean:
Which means:
Which is not possible to solve?
What can I do then to force a constraint on the shape of a higher order polynomial?