## Introduction

This article describes how to extract statistics from a table via a Rule that can then be used for further calculations.

## Requirements

A table with a Rule applied. This article assumes you are already in the **Edit > Edit JavaScript** Rule view specified in How to Customize a Rule.

## Method

### Referencing statistics

Displayr differentiates between statistics in cells, to the right and below a table. You can see these in the **object inspector** under** Inputs > STATISTICS > Cells/Right/Below**. In Table JavaScript these are referenced separately as follows:

table.statistics

right_table.statistics

below_table.statistics

In each case, only the statistics that are currently being displayed in a table will be included.

If you wish to return a list of all statistics that can be computed from this table, you can instead append the `availableStatistics`

property to the appropriate table statistic location:

table.availableStatistics

right_table.availableStatistics

below_table.availableStatistics

Note, not all tables will have each of these types of statistics:

- A
**Nominal**,**Ordinal**,**Binary - Multi**,**Binary - Multi (Compact)**or**Number - Multi**summary table will only have*cell*and*below*statistics. - A
**Nominal - Multi**or**Ordinal - Multi**summary table will only have*cell*and*right*statistics. - A crosstab,
**Binary - Grid**or**Number - Grid**will include*cell*,*right*and*below*statistics. - When you switch rows and columns, the
*right*and*below*statistics will be reversed.

You can check whether *right* or *below* statistics exist by using the below functions which will return* true* or *false*:

belowTableExists()

rightTableExists()

Note, you must include `includeWeb('Table JavaScript Utility Functions');`

at the top of the Rule in this case as the underlying code for these functions only exists in this online library.

### Referencing values from a statistic

You can return the values of a statistic by using the `get`

function:

var cell_vals = table.get("%");

var right_vals = right_table.get("Sum");

var below_vals = below_table.get("Average");

In this example, *cell_vals* will, for example, ‘get’ the statistic values for every cell in the table across all rows and columns.

One thing to note here is that this function uses the original statistic name, that is the name from Displayr's sister product, Q. To avoid having to know the Q statistic name when different, you can instead use the *Table JavaScript Utility* function `getOriginalName`

. In the below example, we return the original name for **Column Sample Size** (which is **Column n**) and pass this instead into the `get`

function:

var stat = getOriginalName("Column Sample Size");

var below_vals = below_table.get(stat);

If you want to have a more flexible Rule that uses the primary statistic, you can combine the `get`

function with the `statistics`

property:

table.get(table.statistics[0])

The format of the `get`

function is a two-dimensional array, where the rows are in the first index and the columns in the second index. So an array of cell statistics in a table might look like this:

[[col1-row1,col2-row1, ...],[col1-row2,col2-row2, ...]]

Using the

reference format, *array*[*row index*][*column index*]`vals[0][0]`

in this case would be the first table cell, that is *col1-row1* for the array.

Note that for one-dimensional SUMMARY tables, a two-dimensional array will still be returned, with only one column in the second dimension. The value type will be based on whether the returning statistic is text or numeric.

## See Also

How to Create a Custom Statistic or Calculation via a Rule

How to Modify Table Cells Using a Rule

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