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# Math 445 Lab 6: 3D graphics

Important matlab commands: linspace, meshgrid, pcolor, surf, contour, surfc, contourf, quiver, mesh, load, subplot, pcolor, shading.

## Problem 1: pcolor, meshgrid, shading, subplot

Skim the Matlab documentation for linspace, meshgrid, and pcolor. Create a 2D mesh from −π to π with 30 points in both the x and y directions. Then for each position in the mesh let z = cos(x) sin(y). Use pcolor, axis equal, and axis tight to generate this figure:

But don't you hate those ugly black lines? You can get rid of them with the shading command. Use subplot and the shading command to generate this figure:

## Problem 2: surf

Create a 2D mesh from −π to π with 20 points in both the x and y directions, let z = cos(x) sin(y) pointwise, and then recreate this figure using the surf and colorbar commands.

## Problem 3: surf in the shade

Create a 2D mesh from −10 to 10 with 100 points in both the x and y directions, let and z = 5 sin(r)/r. Then recreate Figure 4 using the surf and shading commands.