How to do Calculations in Drop-Down Boxes – Displayr Help

This article describes how to use sub-sections of larger tables and even custom R-based calculations in tables and visualizations.

For example, here we have a table that analyzes respondents' perceptions toward various colas, but we only want to graph a couple of them.

We would like to create a bar chart of the data, but rather than graph the entire table, we would like to create a graph of just the first column labeled Feminine.

Requirements

A Displayr document
Familiarity with Displayr's point-and-click R code interface - How to Use Point and Click Inside R Code
Optional: If programming custom calculations some basic knowledge of programming with R - How to Learn R

Method 1 - Table That is a Subsection of a Larger Table

From the toolbar, select Table > Paste or Enter Table
Select an existing table from the DATA SOURCE > Output in 'Pages' dialog. If you don't have a table, you can select the variables you want in the Variables in 'Data' box. You can also click Paste or type data to enter the data from a spreadsheet.
From the Output in 'Pages' menu, select Enter a Calculation or value.
In the Output in 'Pages' box type the table name and the rows/columns you want. In this example, we entered table.Brand.attitude[1:3,] which will extract the first 3 rows of the table.
Type ENTER
This will create a sub-table which just contains the rows pertaining to Coca-Cola products.

Method 2 - A Visualization Based on a Subsection of a Larger Table

Create the table you want to visualize.
Select the table, and in the Object Inspector, select Table > Properties > General and take note of the name of the table
From the toolbar, select Table > Paste or Enter Table
From the DATA SOURCE > Output in 'Pages' menu, select Enter a calculation or value. (Be sure to take note of the table name in the Output in Pages' box)
In the Output in 'Pages' box, type the table name and the rows/columns you want. In this example, we entered table.q5[,1] which extracts column 1 ("Feminine") and all rows.
Click ENTER
The results are as follows:
In the Object Inspector, select OUTPUT > Visualization > Bar > Bar
The results are as follows:

Method 3 - A Visualization Based on a Custom Calculation

Create the table you want to visualize.
From the toolbar, select Table > Paste or Enter Table
From the DATA SOURCE > Output in 'Pages' menu, select Enter a calculation or value.
To display the difference between column 1 (Feminine) and column 2 (Health Conscious), in the Output in 'Pages' box, we can subtract column 2 from column 1 by typing table.q5.3[,1]-table.q5.3[,2]

The results are as follows:
In the Object Inspector, select OUTPUT > Visualization > Bar > Bar
The results are as follows: