# How to Invert a Multivariate Interpolating Function? [duplicate]

• Perhaps something like Maximize[{g[x,y], f[x,y]==C}, {x,y}]? Or NMaximize etc. Hard to tell without some code to play with. – Michael E2 Feb 25 '14 at 23:38
• Do you mean you used NDSolve (not NSolve)? For finding zeros of interpolating functions, see this answer. – Szabolcs Feb 26 '14 at 1:09
• Were this question clarified with even a minimal example, it would become clear that it is not a duplicate of the linked Q&A. (For instance, I don't think this problem can be solved with WhenEvent.) – Michael E2 May 28 at 13:48