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<div>Thanks! I have. https://github.com/matplotlib/matplotlib/issues/5520</div>
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<span style="font-weight:bold">From: </span>Jens Nielsen <<a href="mailto:jenshnielsen@gmail.com">jenshnielsen@gmail.com</a>><br>
<span style="font-weight:bold">Date: </span>Thursday, November 19, 2015 at 9:34 AM<br>
<span style="font-weight:bold">To: </span>csmit <<a href="mailto:christine.e.smit@nasa.gov">christine.e.smit@nasa.gov</a>>, Nathan Goldbaum <<a href="mailto:nathan12343@gmail.com">nathan12343@gmail.com</a>><br>
<span style="font-weight:bold">Cc: </span>"<a href="mailto:matplotlib-users@python.org">matplotlib-users@python.org</a>" <<a href="mailto:matplotlib-users@python.org">matplotlib-users@python.org</a>><br>
<span style="font-weight:bold">Subject: </span>Re: [Matplotlib-users] odd behavior with 'nearest' interpolation<br>
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<div dir="ltr">It seem like this is a genuine bug but I am not sure how to fix it. Can you submit a bug report at Github so we are sure that this is captured? At github you can attach pictures
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<div>Best Jens</div>
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<div dir="ltr">On Thu, 19 Nov 2015 at 14:25 Smit, Christine E. (GSFC-610.2)[TELOPHASE CORP] <<a href="mailto:christine.e.smit@nasa.gov">christine.e.smit@nasa.gov</a>> wrote:<br>
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<div>Yes. It works with 'none.' The problem is that sometimes we need to create images with low inflation factors. So, our data is nxm data points and we want a 2nx2m image or a 3nx3m image. We're currently getting around this bug by using 'none' to create
an nxm image and then using imagemagick's convert to resize.</div>
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<span style="font-weight:bold">From: </span>Jens Nielsen <<a href="mailto:jenshnielsen@gmail.com" target="_blank">jenshnielsen@gmail.com</a>><br>
<span style="font-weight:bold">Date: </span>Wednesday, November 18, 2015 at 6:28 AM<br>
<span style="font-weight:bold">To: </span>Nathan Goldbaum <<a href="mailto:nathan12343@gmail.com" target="_blank">nathan12343@gmail.com</a>>, csmit <<a href="mailto:christine.e.smit@nasa.gov" target="_blank">christine.e.smit@nasa.gov</a>><br>
<span style="font-weight:bold">Cc: </span>"<a href="mailto:matplotlib-users@python.org" target="_blank">matplotlib-users@python.org</a>" <<a href="mailto:matplotlib-users@python.org" target="_blank">matplotlib-users@python.org</a>><br>
<span style="font-weight:bold">Subject: </span>Re: [Matplotlib-users] odd behavior with 'nearest' interpolation<br>
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<div dir="ltr">I can confirm this. The issue is notable with a dpi lower than 10 or so and seems to get worse as it is lowered towards 1.
<div>Can you try plotting the image with interpolation='none' If I do that I get the correct behaviour. 'none' is probably the correct setting if you wish to match </div>
<div>image matrix 1to1 to png coords anyway.<br>
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<div>@nathan The image in the notebook is plotted with a different dpi and works correctly. </div>
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<div>best Jens</div>
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<div dir="ltr">On Tue, 17 Nov 2015 at 22:38 Nathan Goldbaum <<a href="mailto:nathan12343@gmail.com" target="_blank">nathan12343@gmail.com</a>> wrote:<br>
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<div dir="ltr">This seems to be working ok for me: <a href="https://gist.github.com/faa6b4008a8e3db68f46" target="_blank">https://gist.github.com/faa6b4008a8e3db68f46</a></div>
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<div class="gmail_quote">On Tue, Nov 17, 2015 at 4:22 PM, Smit, Christine E. (GSFC-610.2)[TELOPHASE CORP]
<span dir="ltr"><<a href="mailto:christine.e.smit@nasa.gov" target="_blank">christine.e.smit@nasa.gov</a>></span> wrote:<br>
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<div style="font-family:Calibri,sans-serif">Hi! I am using matplotlib v 1.4.3 with Python 2.7.10 :: Anaconda 2.4.0 (64-bit).</div>
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<div style="font-family:Calibri,sans-serif">What I am doing here is creating a 7x7 pixel image from a 7x7 matrix. I expect to see one pixel per data point, but that's not what I'm seeing. Instead of a diagonal make up of single pixels, I get an odd 2x2 pixel
blob in the middle of the correct one pixel diagonal.</div>
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<div><font face="Courier">---------------------------------------------------------------------------</font></div>
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<div><font face="Courier">import numpy as np</font></div>
<div><font face="Courier">import matplotlib.pylab as plt</font></div>
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</font></div>
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</font></div>
<div><font face="Courier">if __name__ == "__main__":</font></div>
<div><font face="Courier"> n = 7</font></div>
<div><font face="Courier"> data = np.identity(n, float)</font></div>
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</font></div>
<div><font face="Courier"> # Create an nxn size figure with no frame</font></div>
<div><font face="Courier"> fig = plt.figure(figsize=(n, n), frameon=False)</font></div>
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</font></div>
<div><font face="Courier"> # make the axes to the edge of the figure</font></div>
<div><font face="Courier"> ax = plt.Axes(fig, [0.0, 0.0, 1.0, 1.0])</font></div>
<div><font face="Courier"> # turn the axes off</font></div>
<div><font face="Courier"> ax.set_axis_off()</font></div>
<div><font face="Courier"> # add the axes to this figure</font></div>
<div><font face="Courier"> fig.add_axes(ax)</font></div>
<div><font face="Courier"> # show the data. Don't do any interpolation.</font></div>
<div><font face="Courier"> ax.imshow(data, interpolation='nearest', origin='lower',aspect='auto')</font></div>
<div><font face="Courier"> # Save the figure at 1 dot per inch, which should mean 1 data point per</font></div>
<div><font face="Courier"> # pixel</font></div>
<div><font face="Courier"> fig.savefig("image.png", dpi=1)</font></div>
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<div style="font-family:Calibri,sans-serif">Since I'm not sure that if I can attach the png image I get, here is a ppm version of the image I get (between the ------). Save this image.ppm minus the dashes and you should be able to open it in something like
gimp.<br>
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<font face="Courier">---------------------------------------------------------------------------<br>
P3<br>
# CREATOR: GIMP PNM Filter Version 1.1<br>
7 7<br>
255<br>
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</font><font face="Courier">---------------------------------------------------------------------------<br>
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<font face="Calibri">Thanks.<span><font color="#888888"><br>
Christine</font></span></font><br>
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