title: idl strange symbols in file
body: <p>I've written several IDL programs to analyse some data. To keep it simple the programs read in some time varying data and calculate the fourier spectrum. This spectrum is written to file using this code:</p>
  
  <pre><code>openw,3,filename        
  printf,3,[transpose(freq),transpose(power)],format='(e,e)'
  close,3 
  </code></pre>
  
  <p>The file is then read by another program using this code:</p>
  
  <pre><code>rdfloat,filename,freq,power,/double
  </code></pre>
  
  <p>The rdfloat procedure can be found here: <a href="http://idlastro.gsfc.nasa.gov/" rel="nofollow">http://idlastro.gsfc.nasa.gov/</a></p>
  
  <p>The error i get when trying to read the a file is: "Input conversion error. Unit: 101"
  When i delve in to the file being read, i notice several types of unrecognised characters. I dont know if these are a result of the writing to the file or some thing else related to the number of files being created (over 300 files)</p>
  
  <p>These symbols/characters are in the place of a single number:</p>
  
  <pre><code>&lt; dle&gt; &lt; dc1&gt; &lt; dc2&gt; &lt; dc3&gt; &lt; dc4&gt; &lt; can&gt; &lt; nak&gt; &lt; em&gt; &lt; soh&gt; &lt; syn&gt;
  </code></pre>
  
  <p>Example of what appears in the file being read, Note they are not consecutive lines.</p>
  
  <pre><code>7.7346&lt; dle&gt;18165493007e+01   8.4796811549010105e+00
  7.7354408697119453e+01   1.04459538071&lt; dc2&gt;1749e+01
  7.7360701595839&lt; can&gt;28e+01   3.0447318983094189e+00
  </code></pre>
  
  <p>Whenever I run the procedures that write the files, there is always at least one file that has some or all of these characters. The file/s that contains these characters is always different.</p>
  
  <p>Can anyone explain what these symbols are and what I might be doing to create them as well as how to ensure they are not written to file?</p>