title: AttributeError: 'numpy.ndarray' object has no attribute 'split'
body: <p>I am trying to answer the following question 
  "A colleague has produced a file with one DNA sequence on each line. Download the file and load it into Python using numpy.loadtxt(). You will need to use the optional argument dtype=str to tell loadtxt() that the data is composed of strings.</p>
  
  <p>Calculate the GC content of each sequence. The GC content is the percentage of bases that are either G or C (as a percentage of total base pairs). Print the result for each sequence as "The GC content of the sequence is XX.XX%" where XX.XX is the actual GC content. Do this using a "formatted strings". "</p>
  
  <p>Having imported the file of dna sequences and joining these together I now want to split the string into 5 sequences (corresponding to each of the 5 rows) to then start the calculations... </p>
  
  <h2>NB: This is the file source: <a href="http://www.programmingforbiologists.org/data/dna_sequences_1.txt" rel="nofollow">http://www.programmingforbiologists.org/data/dna_sequences_1.txt</a></h2>
  
  <p>This is my code:</p>
  
  <pre><code>import numpy
  dna_data=numpy.loadtxt("dna_sequences",dtype=str)
  ",".join(dna_data)
  seq1,seq2,seq3,seq4,seq5=dna_data.split(",",4)
  </code></pre>
  
  <p>I am getting this error message:
  AttributeError: 'numpy.ndarray' object has no attribute 'split' </p>
  
  <p>Please help!!!</p>