title: Reading multiple excel workbooks from a subdirectory into one dataframe
body: <p>This command allows me to read all of the .xlsx files from the current directory into the dataframe.</p>
  
  <pre><code>df &lt;- map_df(list.files(), ~ read_xlsx(., col_types = 
                c("text", "text", "text", "text", "text", "text", "text", "text", 
                  "text", "numeric", "text"))) 
  </code></pre>
  
  <p>The problems is that I would like to put all of the excel files into a subdirectory called files, such that it would change like this</p>
  
  <pre><code> df &lt;- map_df(list.files("files"), ~ read_xlsx(., col_types = 
                    c("text", "text", "text", "text", "text", "text", "text", "text", 
                      "text", "numeric", "text"))) 
  </code></pre>
  
  <p>This creates a problem as far as the path is concerned, since the list files reads from the "files" directory, and the path does not have files/first.xlsx, but first.xlsx, which creates a problem reading the files from the read_xlsx command.  What do I change in the read_xlsx to make sure when it is reading the list of files, it will add the subdirectory titled "files"?</p>