Level curves The two main ways to visualize functions of two variables is via graphs and level curves Both were introduced in an earlier learning module Level curves for a function z = f ( x, y) D ⊆ R 2 → R the level curve of value c is the curve C in D ⊆ R 2 on which f C = c Notice the critical difference between a level curve CPlot level curves (contour lines) of the matrix z, using the contour matrix c computed by contourc from the same arguments;Contour plots are well known from the presence of contour lines on many maps Contour lines indicate constant elevations A peak is characterized by a series of nested closed paths The following graph shows this for the peak at $(x,y)=(0,0)$
Level Sets Ximera