Just type the commands, not the comments, which are only there as a kind of explanation of what you should see. Later, as you use Matlab, you will use the semicolon to keep the screen from getting too cluttered with unnecessary output. Just as we had to set up the independent variable t for the curve, now we have to set up the independent variables X and Y for the surface. The results were a little awkward, though. This week we will use a parametrization of those surfaces which gets around that problem.
Parameters are like coordinates intrinsic to the surface.
These angles parameterize the surface. Latitude ranges from 90 degrees at the north pole to -90 degrees at the south pole. Longitude ranges from 0 degrees at the Greenwich meridian to 360 degrees after one circuit of the globe. Once you calculate these arrays, as we did above, 'surf' shows you the points in 3-space. Your commands will always be just one line long, so you should always end the line with a semicolon, but sometimes you will forget.