[R] Inverse

Zeljko Vrba zvrba at ifi.uio.no
Thu May 21 12:50:17 CEST 2009


On Thu, May 21, 2009 at 08:36:27PM +1000, Kon Knafelman wrote:
> 
> I have coded the following polynomial function
> 
> y= function(x) x^3-2*x^2+1
> 
> I need to find the inverse of this, but the code i am using now isnt returning what i want it to.
> 
This function is not injective, so the inverse does not exist.  For example,
y==0.5 has three solutions: -0.452, 0.597, 1.855




More information about the R-help mailing list