I dont have "imshow" command in my matlab 2012b,,,,is it because i don haver image processing toolbox
You can use image() without the Image Processing Toolbox. You can also use imagesc() but it applies some weird colormap by default that you'll most likely need to correct with colormap() function to a more appropriate colormap, like gray. image() applies a grayscale color map by default. With either one you can still call colormap to apply whatever colormap you want.