# Refactoring R Code

Architect contains easy-to-use tools to quickly make alterations to your code. Below, we display how to use these functionalities.

## Extracting Local Variables

Suppose we have some expressions that are reused throughout our code. In the example below, we have repeated instances of the expression:

profit > 0 & revenue > 50000


To clean up our code, we may be interested in assigning this expression to a variable, and replacing all instances of said expression by our new variable. We can do this by highlighting the specified code and selecting ‘Source > Extract Local Variable…'. The extraction is shown below.

## Renaming Variables in a Selected Region

In the Tips and Tricks Section, we showed how to rename all instances of a variable in an entire document. However, often one wishes to rename a variable in just a specific section of the code.

We can do this by selecting a given section of code and selecting Source > Rename in Selected Region…. This opens a window the displays all variables within the selected region. Navigate to a variable and type another name in the New Name column to rename that variable in the highlighted region.

## Converting Code into a Function

In Architect, a chunk of code can be transformed into a function with the click of a button. Simply highlight the desired code and select Source > Extract R Function…. Architect will automatically detect the function’s necessary input parameters, at which point you can specify their order in the function call. The code is wrapped into a function, and a function call is given underneath the definition.

In the example below, we wrap some code for a residual plot into a ‘plotResiduals’ function that takes ‘x’ and ‘y’ as inputs.