title: Read in data from .txt file (no header, no separator)
body: <p>I have a large dataset (~ 200MB) stored in a .txt-file which I need to read into R. Unfortunately there are <em>no separators</em> (like " " or ",") between the values of the variables and there is <em>no header file</em>.</p>
  
  <p>But there is a codebook, which gives the variable names and also specifies which column belongs to which variable. Some of the variable take one column of space, some take more (so <code>read.fwf</code> won't work); but their width is the same for all cases.</p>
  
  <p>I possibly only have to read in a few of these variables, so I expect that I will just have to <strong>select the necessary columns and name the variables</strong>. What would be an elegant solution to do this (and maybe even preselect meaningful variable types)?</p>