Changeset 64eecf7 in sasmodels for sasmodels/models/core_shell_ellipsoid.py

Timestamp:

Sep 5, 2017 11:40:09 AM (7 years ago)

Author:

Paul Kienzle <pkienzle@…>

Branches:

master, core_shell_microgels, costrafo411, magnetic_model, ticket-1257-vesicle-product, ticket_1156, ticket_1265_superball, ticket_822_more_unit_tests

Children:

30b60d2

Parents:

a53bf6b (diff), 142a8e2 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' into ticket-510

File:

• sasmodels/models/core_shell_ellipsoid.py (modified) (5 diffs)

sasmodels/models/core_shell_ellipsoid.py

@@ -25 +25 @@
 ellipsoid. This may have some undesirable effects if the aspect ratio of the
 ellipsoid is large (ie, if $X << 1$ or $X >> 1$ ), when the $S(q)$
-- which assumes spheres - will not in any case be valid.  Generating a 
-custom product model will enable separate effective volume fraction and effective 
+- which assumes spheres - will not in any case be valid.  Generating a
+custom product model will enable separate effective volume fraction and effective
 radius in the $S(q)$.
 
@@ -46 +46 @@
     :nowrap:
 
-    \begin{align}    
+    \begin{align}
     F(q,\alpha) = &f(q,radius\_equat\_core,radius\_equat\_core.x\_core,\alpha) \\
     &+ f(q,radius\_equat\_core + thick\_shell,radius\_equat\_core.x\_core + thick\_shell.x\_polar\_shell,\alpha)
-    \end{align} 
+    \end{align}
 
 where
- 
+
 .. math::
 
@@ -79 +79 @@
    F^2(q)=\int_{0}^{\pi/2}{F^2(q,\alpha)\sin(\alpha)d\alpha}
 
+For oriented ellipsoids the *theta*, *phi* and *psi* orientation parameters will appear when fitting 2D data,
+see the :ref:`elliptical-cylinder` model for further information.
 
 References
@@ -134 +136 @@
     ["sld_shell",     "1e-6/Ang^2", 1,   [-inf, inf], "sld",         "Shell scattering length density"],
     ["sld_solvent",   "1e-6/Ang^2", 6.3, [-inf, inf], "sld",         "Solvent scattering length density"],
-    ["theta",         "degrees",    0,   [-inf, inf], "orientation", "Oblate orientation wrt incoming beam"],
-    ["phi",           "degrees",    0,   [-inf, inf], "orientation", "Oblate orientation in the plane of the detector"],
+    ["theta",         "degrees",    0,   [-360, 360], "orientation", "elipsoid axis to beam angle"],
+    ["phi",           "degrees",    0,   [-360, 360], "orientation", "rotation about beam"],
     ]
 # pylint: enable=bad-whitespace, line-too-long
@@ -151 +153 @@
     return ellipsoid_ER(polar_outer, equat_outer)
 
-
-demo = dict(scale=0.05, background=0.001,
-            radius_equat_core=20.0,
-            x_core=3.0,
-            thick_shell=30.0,
-            x_polar_shell=1.0,
-            sld_core=2.0,
-            sld_shell=1.0,
-            sld_solvent=6.3,
-            theta=0,
-            phi=0)
+def random():
+    import numpy as np
+    V = 10**np.random.uniform(5, 12)
+    outer_polar = 10**np.random.uniform(1.3, 4)
+    outer_equatorial = np.sqrt(V/outer_polar) # ignore 4/3 pi
+    # Use a distribution with a preference for thin shell or thin core
+    # Avoid core,shell radii < 1
+    thickness_polar = np.random.beta(0.5, 0.5)*(outer_polar-2) + 1
+    thickness_equatorial = np.random.beta(0.5, 0.5)*(outer_equatorial-2) + 1
+    radius_polar = outer_polar - thickness_polar
+    radius_equatorial = outer_equatorial - thickness_equatorial
+    x_core = radius_polar/radius_equatorial
+    x_polar_shell = thickness_polar/thickness_equatorial
+    pars = dict(
+        #background=0, sld=0, sld_solvent=1,
+        radius_equat_core=radius_equatorial,
+        x_core=x_core,
+        thick_shell=thickness_equatorial,
+        x_polar_shell=x_polar_shell,
+    )
+    return pars
 
 q = 0.1