How would I go about generating a blank image with a yellow background?

A portion of my assignment requires that I perform the following:

Generate a 200x 200 image using Matlab. Make the image with yellow background.

The search function provided me with the answer on how to make a blank image of the proper size by using this command blankimage=zeros(200,200). How would I go about making the background of the generated image yellow or would there be an easier way to generate the image?

Thank you in advance for any help provided.

Answer 1

[Walter Roberson]

blankimage = ones(200,200,3);
blankimage(:,:,3) = 0;

[integra-t]

This worked perfectly. Thanks again for your help Walter!