Changeset 54a5024 in sasmodels for explore

Timestamp:

Feb 8, 2018 5:17:59 PM (7 years ago)

Author:

Paul Kienzle <pkienzle@…>

Branches:

master, core_shell_microgels, magnetic_model, ticket-1257-vesicle-product, ticket_1156, ticket_1265_superball, ticket_822_more_unit_tests

Children:

e309e23

Parents:

a09d55d

Message:

multiscat: use correct weightings for the multiscattering contributions

File:

• explore/multiscat.py (modified) (2 diffs)

explore/multiscat.py

@@ -170 +170 @@
 
 def scattering_power(Iq, n):
+    """
+    Calculate the nth scattering power as a distribution.  To get the
+    weighted contribution, scale by $\lambda^k e^{-\lambda}/k!$.
+    """
     scale = np.sum(Iq)
     F = _forward_fft(Iq/scale)
-    result = scale * _inverse_fft(F**n)
+    result = _inverse_fft(F**n)
     return result
 
@@ -181 +185 @@
     Given a probability p of scattering with the thickness, the expected
     number of scattering events, $\lambda$ is $-\log(1 - p)$, giving a
-    Poisson weighted sum of single, double, triple, ... scattering patterns.
-    The number of patterns used is based on coverage (default 99%).  If
-    return_poi
+    Poisson weighted sum of single, double, triple, etc. scattering patterns.
+    The number of patterns used is based on coverage (default 99%).
     """
     L = -np.log(1-p)