title: Matplotlib can't suppress figure window
body: <p>I'm having trouble with matplotlib insisting on displaying a figure wnidow even when I haven't called show().</p>
  
  <p>The function in question is:</p>
  
  <pre><code>def make_plot(df):
      fig, axes = plt.subplots(3, 1, figsize=(10, 6), sharex=True)
      plt.subplots_adjust(hspace=0.2)
  
      axes[0].plot(df["Date_Time"], df["T1"], df["Date_Time"], df["T2"])
      axes[0].set_ylabel("Temperature (C)")
      axes[0].legend(["T1", "T2"], bbox_to_anchor=(1.12, 1.1))
      axes[1].semilogy(df["Date_Time"], df["IGP"], df["Date_Time"], df["IPP"])
      axes[1].legend(["IGP", "IPP"], bbox_to_anchor=(1.12, 1.1))
      axes[1].set_ylabel("Pressure (mBar)")
      axes[2].plot(df["Date_Time"], df["Voltage"], "k")
      axes[2].set_ylabel("Voltage (V)")
      current_axes = axes[2].twinx()
      current_axes.plot(df["Date_Time"], df["Current"], "r")
      current_axes.set_ylabel("Current (mA)")
      axes[2].legend(["V"], bbox_to_anchor=(1.15, 1.1))
      current_axes.legend(["I"], bbox_to_anchor=(1.14, 0.9))
  
      plt.savefig("static/data.png")
  </code></pre>
  
  <p>where df is a dataframe created using pandas. This is supposed to be in the background of a web server, so all I want is for this function to drop the file in the directory specified. However, when it executes it does this, and then pulls up a figure window and gets stuck in a loop, preventing me from reloading the page. Am I missing something obvious?</p>
  
  <p>EDIT: Forgot to add, I am running python 2.7 on Windows 7, 64 bit.</p>