title: How can i get frequency in time domain from a wav file?
body: <p>In other words, I am trying to play a .wav file and for doing this I need to know the frequency and how much it lasts; the API I am using has a method that need as parameter a vector with two fields (frequency and time)!</p>
  
  <p>I tried to use fast fourier transformation but it gives me the frequency and the magnitude!</p>
  
  <p>mag<br>
    /\
    |
    |
   -|------> freq</p>
  
  <p>But I need something like this:
  freq
    /\
    |
    |
   -|------>time</p>
  
  <p>I want to know if is possible to get these informations from a wav file!</p>