Paginate an array

My controller code is as follows,

  def index
  end

  def show
    if params[:cat_id]
    # cat_id is fetched from DB(a table with two columns id and name)
    #mapped as cat_id in routes file
      @articles = Article.find_all_by_name(params[:cat_id].gsub(/\-/, '
'))
      render :action => :index
    end
  end

How to do pagination using will_paginate on this.

Here @articles is an array which fetches articles based on category
names. The output of this is as follows,

An index page with 3 category names and relevant articles under each
category. Now i need to apply will_paginate under each category in index
page. How to do this. Adding ".paginate(:page => params[:page],
:per_page =>3) returns undefined method 'total pages' since its an
array. Could you please advise me as to how pagination can be done.
Further, the url structure is article/categoryname/articlename (formed
using slug).

Use where instead of the find_by helpers.

`Article.where(“name = ?”, params[:cat_id].gsub(/-/, ‘’)).paginate({

:page => params[:page], :per_page =>3 })`

find_all_by_* does it’s job literally, it finds them all and it defeats the logic in it’s name to add pagination to it. So if you want pagination use where.