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SUROJ
Anybody know how to find point with zero gradient in contour plot?
Maxima: nearby gradient vectors all point toward the critical point (function increasing) Minima: nearby gradient vectors all point away from critical point (function decreasing) Saddles: some nearby gradients point toward, others away.
The gradient is the 3d equivalent of slope from 2d calculus. The gradient is zero at a minima or maxima. (because at that point the slope is neither increasing (+) nor decreasing (-)) So looking at your contour plot... where is the minima (or maxima)? That's where the gradient is zero.
@mathteacher1729 shouldn't that be around [0.3,0.3] in above contour plot?
@SUROJ Yes, that sounds about right. You'd need more contour lines to be sure,though.