PeaksInRegion v1

../_images/PeaksInRegion-v1_dlg.png

PeaksInRegion dialog.

Summary

Find peaks intersecting a box region.

Properties

Name Direction Type Default Description
CheckPeakExtents Input boolean False Include any peak in the region that has a shape extent extending into that region.
InputWorkspace Input IPeaksWorkspace Mandatory An input peaks workspace.
CoordinateFrame Input string Mandatory What coordinate system to use for intersection criteria? DetectorSpace: Real-space coordinates. Q (lab frame): Wave-vector change of the lattice in the lab frame. Q (sample frame): Momentum in the sample frame. HKL. Allowed values: [‘Detector space’, ‘Q (lab frame)’, ‘Q (sample frame)’, ‘HKL’]
PeakRadius Input number 0 Effective peak radius in CoordinateFrame
OutputWorkspace Output TableWorkspace Mandatory An output table workspace. Two columns. Peak index into input workspace, and boolean, where true is for positive intersection.
Extents Input dbl list -50,50 A comma separated list of min, max for each dimension, specifying the extents of each dimension. Optional, default +-50 in each dimension.

Description

Determines which peaks intersect a defined box region in either QLab, QSample or HKL space. Similar to PeaksOnSurface v1.

Usage

Example - Peaks inside and outside of a defined region

# Load an MDEventWorkspace (QLab) containing some SC diffration peaks
mdew = Load("TOPAZ_3680_5_sec_MDEW.nxs")
# Find some peaks. These are all unindexed so will have HKL = [0,0,0]
peaks = FindPeaksMD(InputWorkspace=mdew, MaxPeaks=1)

# Find peaks in region when the Peak sits in the centre of a box
in_box_table = PeaksInRegion(peaks, CoordinateFrame='HKL', PeakRadius=0.1, Extents=[-1.0,1.0,-1.0,1.0,-1.0,1.0], CheckPeakExtents=True)
print in_box_table.row(0)

# Find peaks in region when the peak is just outside the box (by radius)
just_outside_box_table = PeaksInRegion(peaks, CoordinateFrame='HKL', PeakRadius=0.999, Extents=[1.0,2.0,-1.0,1.0,-1.0,1.0], CheckPeakExtents=True)
print just_outside_box_table.row(0)

# Find peaks in region when the peak is just inside the box (by radius)
just_intesecting_box_table = PeaksInRegion(peaks, CoordinateFrame='HKL', PeakRadius=1.00, Extents=[1.0,2.0,-1.0,1.0,-1.0,1.0], CheckPeakExtents=True)
print just_intesecting_box_table.row(0)

Output:

{'Distance': 0.0, 'PeakIndex': 0, 'Intersecting': True}
{'Distance': -1.0, 'PeakIndex': 0, 'Intersecting': False}
{'Distance': -1.0, 'PeakIndex': 0, 'Intersecting': True}

Categories: Algorithms | Crystal\Peaks

Source

C++ source: PeaksInRegion.cpp

C++ header: PeaksInRegion.h