Customize the wordpress shortcode : recent_blog

Find the php file for shortcode in customtheme :

File Location:

webroot\wp-content\themes\themename\backend\shortcode.php

Find the below code :

 function recent_blog($atts) {
     extract(shortcode_atts(array('limit' => '3', 'number' => '3','fullpage' => 'no' ), $atts));  

    $number = $limit;
 $categoryid = $category; // added category slug here...
    $wp_query = new WP_Query(
    array(
    'post_type' => array('post'),
    'showposts' => $number,
    ));
....................
 add_shortcode('recent_blog', 'recent_blog');

add category , category_name - category slug name to filter the post by category

function recent_blog($atts) {
     extract(shortcode_atts(array('limit' => '3', 'number' => '3','fullpage' => 'no', 'category'=>'' ), $atts));  //added slug category  here......'category'=>'' 

    $number = $limit;
 $categoryslug = $category; // added category slug here...
    $wp_query = new WP_Query(
    array(
    'post_type' => array('post'),
    'showposts' => $number,
 'category_name' => $categoryslug , // added category slug here...
    ));
.............
 add_shortcode('recent_blog', 'recent_blog');

Use following shortcode on page/post in content area

[recent_blog limit="5" fullpage="yes" category="slugname"]