Is this a valid PHP code?

Can somebody tell me whether this is a valid PHP code? <?php // This theme uses Featured Images (also known as post thumbnails) for per-post/per-page Custom Header images add_theme_support( 'post-thumbnails' ); // Add support for custom headers. $custom_header_support = array( // The default header text color. 'default-text-color' => '000', // The height and width of our custom header. 'width' => apply_filters( 'twentyeleven_header_image_width', 1000 ), 'height' => apply_filters( 'twentyeleven_header_image_height', 180 ), // Support flexible heights. 'flex-height' => true, // Random image rotation by default. 'random-default' => true, // Callback for styling the header. 'wp-head-callback' => 'twentyeleven_header_style', // Callback for styling the header preview in the admin. 'admin-head-callback' => 'twentyeleven_admin_header_style', // Callback used to display the header preview in the admin. 'admin-preview-callback' => 'twentyeleven_admin_header_image', ); ?> I am trying to change the default header image size (in wp THEME 2011) to a height of 180px but it doesn't seem to work and I don't know what is causing the problem. THANKS. -- Good Guy Website: http://mytaxsite.co.uk Website: http://html-css.co.uk Email: http://mytaxsite.co.uk/contact-us