<div dir="ltr">Sorry I just realized a simple error in my script in generating the mask file with FA thresholded at 0.7. Now the results look fine and there is no nan in the response function any longer. <div><br></div><div>
Zhuang <br><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, May 1, 2013 at 11:55 AM, Zhuang Song <span dir="ltr"><<a href="mailto:zhuang.song@gmail.com" target="_blank">zhuang.song@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Dear Group, <div><br></div><div>In the output response functions produced by estimate_response, there are several cases in my data that have nan in the response functions while others look fine. These image were all acquired and processed with the same methods. I was wondering what might be the reason to get nan in the results. Does it indicate there are some problems in the DWI data? The DTI construction all looks fine for all these data.</div>
<div><br></div><div>Some examples of response functions in my data:</div><div><br></div><p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">378.369 nan nan nan nan </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">374.228 nan nan nan nan </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">410.525 nan nan nan nan </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">364.583 -32.2504 0.4034 -0.0136654 -0.0424694 </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">427.235 -48.645 0.795029 0.0733941 -0.0156282 </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">334.129 -36.3756 0.0756312 0.0734365 -0.0178463 </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">413.255 -43.6258 0.441787 -0.0159834 0.0150817 </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">385.935 -39.2011 0.477614 0.0651567 0.00753772 </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">433.311 nan nan nan nan </p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;font:normal normal normal 12px/normal Helvetica">405.377 nan nan nan nan </p><div> </div><div>In order to generate a group mean response function, I do simple averaging of each coefficient of those individual without any nan's. Does this sound reasonable? </div>
<div><br></div><div>Thanks, </div><span class="HOEnZb"><font color="#888888"><div>Zhuang <br>
</div><div><br></div></font></span></div>
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