see 'MeshDensity' — Number of evaluation points per direction
Control Resolution of Surface Plot
Control the resolution of a surface plot using the 'MeshDensity' option. Increasing 'MeshDensity' can make smoother, more accurate plots while decreasing it can increase plotting speed.
Create two plots in a tiled chart layout. In the first plot, display the parametric surface x=sin(s), y=cos(s), z=(t/10)sin(1/s). The surface has a large gap. Fix this issue by increasing the 'MeshDensity' to 40 in the second plot. fsurf fills the gap, showing that by increasing 'MeshDensity' you increased the resolution.
fsurf(@(s,t) sin(s), @(s,t) cos(s), @(s,t) t/10.*sin(1./s))
title('Default MeshDensity = 35')
fsurf(@(s,t) sin(s), @(s,t) cos(s), @(s,t) t/10.*sin(1./s),'MeshDensity',40)
title('Increased MeshDensity = 40')