title: parsing a txt file in c++
body: <p>Hi I'm coming from C# and have been working with c++ alot lately and I need help,
  I have a text file(500mb) that i need to load into an array(matrix).
  the format on the text file is</p>
  
  <pre><code>specimen  date      result
  E1       111111    0.5
  </code></pre>
  
  <p>How can i just extract out the result of this and put only that into my matrix where each column would represent a different specimen? I know in C# i could eaisly parse this but i dont know how to do it in c++
  thank you for your help ,i just want to know the commands or functions that I would need to know</p>
  
  <pre><code>                 E1 ............En
  result@ time 1   .................
                   .               .
                   . . .  . . . . ..
  result@time n    .................
  </code></pre>
  
  <p>there are 7000 specimens , and 3 years worth of dates , the results range from 0.1 to 20000</p>