title: matplotlib histogram with frequency and counts
body: <p>I have data (from a space delimited text file with two columns)  which is already binned but only a width of 1.  I want to increase this width to about 5.  How can I do this using numpy/matplotlib in Python?  </p>
  
  <p>Using,</p>
  
  <pre><code>data = loadtxt('file.txt')
  x = data[:, 0]
  y = data[:, 1]
  plt.bar(x,y)
  </code></pre>
  
  <p>creates too many bars and using,</p>
  
  <pre><code>plt.hist(data)
  </code></pre>
  
  <p>doesn't plot the histogram appropriately.  I guess I don't understand how matplotlib's histogram plotting works.</p>
  
  <p>See some of the data below.</p>
  
  <pre><code>264 1
  265 1
  266 4
  267 2
  268 2
  269 2
  270 2
  271 2
  272 5
  273 3
  274 2
  275 6
  276 7
  277 3
  278 7
  279 5
  280 9
  281 4
  282 8
  283 11
  284 9
  285 15
  286 19
  287 11
  288 12
  289 10
  290 13
  291 18
  292 20
  293 14
  294 15
  </code></pre>