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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.