Excellent point and no, these are not missing reflections. SigF is not
zero. Also, if I am not mistaken, missing reflections in the MTZ format
are recorded as NaN.
Ed.
On Thu, 2011-02-10 at 12:17 +0000, Eleanor Dodson wrote:
> Are you sure these are real FP=0 or reflections which werent measured
> but have been added for completeness of the h k l list.
> The check is whether the SigF is also 0.00 - in that case they are
> genuinely missing..
>
> Eleanor
>
> On 02/09/2011 11:34 PM, Ed Pozharski wrote:
> > I observe under some conditions that ctruncate sets some reflections
> > amplitudes to zero. AFAIU, this should not be happening as even
> > negative intensities (there are none in this particular dataset) should
> > produce FP>0 upon truncation.
> >
> > 66 out of ~23000 reflections are zeros after ctruncate is applied.
> > Nothing obvious comes up upon inspecting the corresponding hkl's, except
> > that one and only one is always zero (sg is P21212, so these are not
> > systematic absences). One curious thing is that the I/sigma for these
> > reflections is close to the average I/sigma in the highest resolution
> > range (but it varies and these reflections are in all resolution
> > ranges).
> >
> > A bug?
> >
>
--
Edwin Pozharski, PhD, Assistant Professor
University of Maryland, Baltimore
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Then knowledge and wisdom are born along with hypocrisy.
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