Here are some ideas to address the issue:

1. Find a computer with more RAM

2. Get rid of data frames that aren’t needed.

Eliminating unnecessary data frames will release memory.

3. Change the maximum amount of memory allocated for R.

You can increase the memory allocation size of R using the steps below:

• Click the “+” button above “Script” to make an entirely new script.
• Check that the “Load this script whenever the project is open” checkbox is checked.
• Use the command below. The following example sets 32GB as the new maximum memory size:

  Sys.setenv('R_MAX_VSIZE'=32000000000)

• Select “Save”.

*Note: It is important to note that this depends on the specs of your machine. If your system can allocate as high as 16GB, the maximum amount of memory you can give will be 16GB, even when you set 32GB. Above are three solutions that I have used and been successful.