Getting Started    


Two-dimensional arrays can be displayed as images, where the array elements determine brightness or color of the images. For example, the statements

load the file durer.mat, adding three variables to the workspace. The matrix X is a 648-by-509 matrix and map is a 128-by-3 matrix that is the colormap for this image.

The elements of X are integers between 1 and 128, which serve as indices into the colormap, map. Then

reproduces Dürer's etching shown at the beginning of this book. A high resolution scan of the magic square in the upper right corner is available in another file. Type

and then use the up arrow key on your keyboard to reexecute the image, colormap, and axis commands. The statement

adds some twentieth century colorization to the sixteenth century etching. The function hot generates a colormap containing shades of reds, oranges, and yellows. Typically a given image matrix has a specific colormap associated with it. See the colormap reference page for a list of other predefined colormaps.

  Mesh and Surface Plots Printing Graphics