category to page

<?php
/*
Template Name: Blog
*/
get_header(); ?>

    <div id="container">
        <div id="content" role="main">


<?php
// page id 672 will get category ID 20 posts, page 670 will get category 19 posts, page 682 will get both category 19 and 20 posts
if (is_page('672') ) {
$cat = array(20);
} elseif ( is_page('670') ) {
$cat = array(19);
} elseif ( is_page('682') ) {
$cat = array(19,20);
} else {
$cat = '';
}

$showposts = -1; // -1 shows all posts
$do_not_show_stickies = 1; // 0 to show stickies
$args=array(
   'category__in' => $cat,
   'showposts' => $showposts,
   'caller_get_posts' => $do_not_show_stickies
   );

$my_query = new WP_Query($args);

?>

<?php if( $my_query->have_posts() ) : ?>
        <?php while ($my_query->have_posts()) : $my_query->the_post(); ?>
            <?php
            //necessary to show the tags
            global $wp_query;
            $wp_query->in_the_loop = true;
            ?>
            <div <?php post_class() ?> id="post-<?php the_ID(); ?>">


                <div class="entry-post-title"><h3><?php the_title(); ?></h3></div>
                <div class="entry-content-post">
                    <?php the_content('Read the rest of this entry ?'); ?>

       <small><p class="byline">Posted by <?php the_author() ?> on <?php the_time('l, F jS, Y | g:i A') ?> </p></small>


                <!-- <div class="entry-meta">
<?php edit_post_link('Edit this entry', '<span class="entry-editlink">', '</span>'); ?>
                </div> -->

                                </div>
                </div><!-- .post -->

 <?php /* Add a custom field with key "comments" (value is ignored) to turn on comments for a page! */ ?>

<?php if ( get_post_custom_values('comments') ) comments_template(); ?>


<?php endwhile; ?>

    <?php else : ?>
        <h2 class="center">Not Found</h2>
        <p class="center">Sorry, but you are looking for something that isn't here.</p>
        <?php get_search_form(); ?>

    <?php endif; ?>

        <?php comments_template( '', true ); ?>



            </div><!-- #content -->
        </div><!-- #container -->

<?php get_sidebar(); ?>
<?php get_footer(); ?>