29. 2-D resolution functions

sasmodels.resolution2d

#This software was developed by the University of Tennessee as part of the #Distributed Data Analysis of Neutron Scattering Experiments (DANSE) #project funded by the US National Science Foundation. #See the license text in license.txt

class sasmodels.resolution2d.Pinhole2D(data=None, index=None, nsigma=3.0, accuracy='Low', coords='polar')

Bases: Resolution

Gaussian Q smearing class for SAS 2d data

Assumption: equally spaced bins in dq_r, dq_phi space.

Parameters:
  • data – 2d data used to set the smearing parameters

  • index – 1d array with len(data) to define the range of the calculation: elements are given as True or False

  • nr – number of bins in dq_r-axis

  • nphi – number of bins in dq_phi-axis

  • coord – coordinates [string], ‘polar’ or ‘cartesian’

apply(theory)

Smear theory by the resolution function, returning Iq.

q: ndarray = None
q_calc: ndarray = None
class sasmodels.resolution2d.Slit2D(q, q_length, q_width=0.0, q_calc=None, accuracy='low')

Bases: Resolution

Slit aperture with resolution function on an oriented sample.

q points at which the data is measured.

q_length slit length (long axis); assumed to be in the direction of qx

q_width slit width (short axis); assumed to be in the direction of qy; current implementation requires a fixed q_width for all q points.

Please note that this assumption of laboratory-frame qx and qy directions can be inverted by adding or subtracting 90 degrees from the model orientation. For the particular case of USANS, which has a vertical slit of width q_width sweeping through qx, add 90 degrees to the fitted phi angle to find the orientation relative to laboratory frame.

q_calc is the list of q points to calculate, or None if this should be estimated from the q and qx_width.

accuracy determines the number of q_width points to compute for each q. The values are stored in sasmodels.resolution2d.N_SLIT_PERP. The default values are: low=101, med=401, high=1001, xhigh=2001

apply(theory)

Smear theory by the resolution function, returning Iq.

q: ndarray = None
q_calc: ndarray = None