gistfile1.rb

 def photo_set_helper(photos, row_size=8)
    quotient, remainder = photos.count.divmod(row_size)
    capture do  
      - for i in 0..quotient-1
        .row
          - for j in 0..row_size-1 
            = image_tag @photos[i * row_size + j]["s3_url"], :id => "#{@photos[i * row_size +j]["id"]}"
      - if remainder > 0
        .row
          - for j in 0..remainder-1
            = image_tag @photos[quotient * row_size + j]["s3_url"], :id => "#{@photos[quotient * row_size +j]["id"]}"
    end
 end