Hi Nicolas,<div><br></div><div>If you provide the new text that you would like to see in the documentation, I can modify the file and commit the change.</div><div><br></div><div> - David</div><div> <br><br><div class="gmail_quote">

On Mon, May 9, 2011 at 11:29 AM, Nicolas Rannou <span dir="ltr">&lt;<a href="mailto:Nicolas_Rannou@hms.harvard.edu">Nicolas_Rannou@hms.harvard.edu</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">

<div style="word-wrap:break-word">Thanks David, <div><br></div><div>yes such a feature to get the scalar range over all the components would be nice.</div><div>Maybe we should also update the documentation (<a href="http://www.vtk.org/doc/nightly/html/classvtkDataSet.html#a9c8f06877f41b3e1944f2d10281083a6" target="_blank">http://www.vtk.org/doc/nightly/html/classvtkDataSet.html#a9c8f06877f41b3e1944f2d10281083a6</a>).</div>

<div><br></div><div><span style="font-family:&#39;Lucida Grande&#39;, Verdana, Geneva, Arial, sans-serif;font-size:12px"><div style="font-family:&#39;Lucida Grande&#39;, Verdana, Geneva, Arial, sans-serif;font-size:12px;border-top-width:1px;border-top-style:solid;border-top-color:rgb(168, 184, 217);border-left-width:1px;border-left-style:solid;border-left-color:rgb(168, 184, 217);border-right-width:1px;border-right-style:solid;border-right-color:rgb(168, 184, 217);padding-top:6px;padding-right:0px;padding-bottom:6px;padding-left:0px;color:rgb(37, 53, 85);font-weight:bold;background-color:rgb(226, 232, 242);background-repeat:repeat no-repeat">

<table style="font-family:&#39;Lucida Grande&#39;, Verdana, Geneva, Arial, sans-serif;font-size:12px;white-space:nowrap;font-weight:bold;margin-left:6px"><tbody><tr><td style="white-space:nowrap;font-weight:bold;margin-left:6px">

virtual void vtkDataSet::GetScalarRange</td><td>(</td><td style="white-space:nowrap">double </td><td style="color:rgb(96, 32, 32);white-space:nowrap"><em style="font-style:normal">range</em>[2]</td><td>)</td><td><code>[virtual]</code></td>

</tr></tbody></table></div><div style="font-family:&#39;Lucida Grande&#39;, Verdana, Geneva, Arial, sans-serif;font-size:12px;border-bottom-width:1px;border-bottom-style:solid;border-bottom-color:rgb(168, 184, 217);border-left-width:1px;border-left-style:solid;border-left-color:rgb(168, 184, 217);border-right-width:1px;border-right-style:solid;border-right-color:rgb(168, 184, 217);padding-top:2px;padding-right:5px;padding-bottom:2px;padding-left:5px;background-color:rgb(251, 252, 253);border-top-width:0px">

<p style="font-family:&#39;Lucida Grande&#39;, Verdana, Geneva, Arial, sans-serif;font-size:12px">Convenience method to get the range of the scalar data (if there is any scalar data). Returns the (min/max) range of combined point and cell data. If there are no point or cell scalars the method will return (0,1). Note: Update needs to be called to create the scalars. THIS METHOD IS THREAD SAFE IF FIRST CALLED FROM A SINGLE THREAD AND THE DATASET IS NOT MODIFIED</p>

<div><br></div></div></span></div><div><br><div><div>To  highlight that it computes the scalar range on the first component?</div><div><br></div><div>Thanks!</div><div><br></div><font color="#888888"><div>Nicolas</div></font><div>

<div></div><div class="h5"><div><br></div><div>On May 7, 2011, at 5:25 PM, David Gobbi wrote:</div><br><blockquote type="cite"><div>The only way that I know of is to get the range directly from the scalars,<br><br>double range[2];<br>

data-&gt;GetPointData()-&gt;GetScalars()-&gt;GetRange(range, component);<br><br>Personally, I would not be opposed to changing vtkDataSet::ComputeRange()<br>so that it computed the range over all components.<br><br>  David<br>

<br><br>On Sat, May 7, 2011 at 1:37 PM, Nicolas Rannou<br>&lt;<a href="mailto:Nicolas_Rannou@hms.harvard.edu" target="_blank">Nicolas_Rannou@hms.harvard.edu</a>&gt; wrote:<br><blockquote type="cite">Hi David,<br></blockquote>

<blockquote type="cite"><br></blockquote><blockquote type="cite">Thanks for the clarification.<br></blockquote><blockquote type="cite">Which is the best practice to get the scalar range of each component then?<br></blockquote>

<blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">On May 6, 2011, at 5:53 PM, David Gobbi wrote:<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">

<blockquote type="cite">Hi Nicolas,<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">The GetScalarRange() method computes the scalar range of the first component.<br>

</blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">- David<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">On Fri, May 6, 2011 at 3:00 PM, Nicolas Rannou<br></blockquote></blockquote>

<blockquote type="cite"><blockquote type="cite">&lt;<a href="mailto:nicolas_rannou@hms.harvard.edu" target="_blank">nicolas_rannou@hms.harvard.edu</a>&gt; wrote:<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">Hello,<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">I&#39;m experiencing a strange behavior in VTK which might be a bug.<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">It took me a while to locate the issue:<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">

if I create a LUT with a NULL red component:<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  iRed = 0;<br></blockquote></blockquote></blockquote><blockquote type="cite">

<blockquote type="cite"><blockquote type="cite">  iGreen = 255;<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  iBlue = 255;<br></blockquote></blockquote>

</blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  iAlpha = 255;<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  double iRange[2] = {0, 255};<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">

  vtkSmartPointer&lt;vtkLookupTable&gt; lut =<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">      vtkSmartPointer&lt;vtkLookupTable&gt;::New();<br></blockquote>

</blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  double* HSV = vtkMath::RGBToHSV(iRed,iGreen,iBlue);<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">  lut-&gt;SetAlpha(iAlpha);<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  lut-&gt;SetHueRange(HSV[0], HSV[0]);<br></blockquote>

</blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  lut-&gt;SetSaturationRange(1, 1);<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">  lut-&gt;SetValueRange(0, 1);<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  lut-&gt;SetRange(iRange);<br></blockquote></blockquote>

</blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  lut-&gt;Build();<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">I color my image with this LUT:<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  vtkSmartPointer&lt;vtkImageMapToColors&gt; coloredImage =<br></blockquote></blockquote>

</blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">      vtkSmartPointer&lt;vtkImageMapToColors&gt;::New();<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">  coloredImage-&gt;SetLookupTable(iLUT);<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  coloredImage-&gt;SetInput( iImage );<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  coloredImage-&gt;PassAlphaToOutputOff();<br></blockquote></blockquote></blockquote><blockquote type="cite">
<blockquote type="cite">
<blockquote type="cite">  coloredImage-&gt;SetOutputFormatToRGB();<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  coloredImage-&gt;Update();<br></blockquote>

</blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">then:<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">  double* range = coloredImage-&gt;GetOutput()-&gt;GetScalarRange();<br></blockquote></blockquote></blockquote>

<blockquote type="cite"><blockquote type="cite"><blockquote type="cite">returns [0,0].<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">then everything I do with this image is messed up...<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">

If iRed != 0, the scalar range of the &quot;coloredImage&quot; will be correct then my<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">pipeline is working.<br>

</blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite">

Am I doing something wrong?<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">Thanks,<br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><br></blockquote></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">

<blockquote type="cite">Nicolas<br></blockquote></blockquote></blockquote></div></blockquote></div></div></div><br></div></div></blockquote></div><br></div>