Opened 2 years ago

Last modified 15 months ago

#715 new defect

resolution calculation does not check for basis of support between q points

Reported by: pkienzle Owned by:
Priority: minor Milestone: SasView 4.3.0
Component: SasView Keywords:
Cc: Work Package: SasView Bug Fixing

Description

To compute the resolution approximation more accurately all measured q points should have enough calculated q points within the resolution window regardless of how sparsely the data is measured.

sasmodels/resolution.py only extends q beyond the measured end points, it does not check that there is sufficient number of points within dq of each measured q point. This is generally not a problem for SANS since the 1D pattern is computed from the circular average with dense enough spacing, but it could potentially be a problem when datasets from non-overlapping q regions are joined, or when data is excluded from the middle of the q range. It could also be a problem in USANS where q spacing is completely under user control.

Change History (2)

comment:1 Changed 18 months ago by pkienzle

  • Milestone changed from SasView Next Release +1 to SasView 4.2.0

Yet another user wanted to fit a model with an excluded region in the middle. The GUI does not support masking central parts of the q range, and the resolution calculator does not fill the masked range with q calculation points, leading to poorly fitting points at the edges of the masked region.

comment:2 Changed 15 months ago by butler

  • Milestone changed from SasView 4.2.0 to SasView 4.3.0
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