title: How to read only lines that fulfil a condition from a csv into R?
body: <p>I am trying to read a large csv file into R. I only want to read and work with some of the rows that fulfil a particular condition (e.g. <code>Variable2 &gt;= 3</code>). This is a much smaller dataset.</p>
  
  <p>I want to read these lines directly into a dataframe, rather than load the whole dataset into a dataframe and then select according to the condition, since the whole dataset does not easily fit into memory.</p>