assign vs swap out

assign

verb
  • To allot or give (something) as a task. 

  • To give (a value) to a variable. 

  • To designate or set apart (something) for some purpose. 

  • To attribute or sort (something) into categories. 

  • To categorize (someone) as belonging to the male or female sex. 

  • To transfer (property, a legal right, etc.) from one person to another. 

  • To appoint or select (someone) for some office. 

noun
  • An assignee. 

swap out

verb
  • To exchange (something) for (something else). (usually followed by with or for) 

  • To transfer (memory contents) into a swap file. 

  • To exchange (something or someone) for an unused (or less-used) equivalent. 

noun
  • Anything that is swapped out for another; an exchange. 

  • A pre-prepared food item used in place of an unfinished food item in order to cut down the overall preparation time during filming. 

How often have the words assign and swap out occurred in a corpus of books? (source: Google Ngram Viewer )