Sampling data with dplyr

As a single machine cannot efficiently process big data problems, a practical approach is to take samples that we can effectively use to draw conclusions. Here, we will show you how to use dplyr to sample from data.

Getting ready

Ensure that you installed and loaded data.table in your R session. You also need to complete the Enhancing a data.frame with a data.table recipe to load purchase_view.tab and purchase_order.tab as both data.frame and data.table into your R environment.

How to do it…

Perform the following steps to sample data with dplyr:

1. First, we can sample six rows from the data:

   > set.seed(123)
   > sample_n(order.dt, 6, replace = TRUE)
                     Time Action       User     Product Quantity Price
   1: 2015-07-10 09:22:37  order  U46651253 P0004306934        1   750
   2: 2015-07-25 21:42:34  order U232322558 P0014273055        1  3688
   3: 2015-07-13 22:55:33  order  U14804834 P0013147260        1 32900
   4: 2015-07-29 08:48:18  order U364096419 P0003425855...