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\section{XDS Integrater Implementation}

\subsection{Introduction}

Unlike the indexing, integration with XDS is relatively straightforward,
consisting of three stages - definition of the area of the detector
over which to measure reflections, integration of those reflections
and initial scaling and postrefinement. In xia2 the latter stage will be
considered as part of the scaling, though this may feed back to integration
the postrefined XPARM information.

Integration is the first point at which the output files from XDS become 
particularly large, as they contain reflections. They will therefore not
be stored in memory.


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