title: Add rows to variable to create a table - RStudio
body: <p>I'm trying to do a correlation matrix between stocks on RStudio. Each stock has some empty (NA) data in some dates and starts the time series on a different date. Before creating the matrix, I need to create a table (with data.frame or another option) with all the variables (stock prices), but it is not possible because each one has a different amount of rows. There are two possible answers:
  1) How can I add NA data to all the variables that have missing rows in a way to create the table? or;
  2) How can I only keep the rows that have data for all the variables that I need for the correlation matrix?</p>