Changeset eda8b30 in sasmodels for sasmodels/models/stacked_disks.py

Timestamp:

Oct 28, 2017 6:42:15 AM (6 years ago)

Author:

richardh

Branches:

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

Children:

5f8b72b

Parents:

da5536f

Message:

further changes to model docs for orientation calcs

File:

• sasmodels/models/stacked_disks.py (modified) (1 diff)

sasmodels/models/stacked_disks.py

@@ -74 +74 @@
     the layers.
 
-To provide easy access to the orientation of the stacked disks, we define
-the axis of the cylinder using two angles $\theta$ and $\varphi$.
+2d scattering from oriented stacks is calculated in the same way as for cylinders,
+for further details of the calculation and angular dispersions see :ref:`orientation` . 
 
 .. figure:: img/cylinder_angle_definition.png
 
-    Examples of the angles against the detector plane.
+    Angles $\theta$ and $\phi$ orient the stack of discs relative
+    to the beam line coordinates, where the beam is along the $z$ axis. Rotation $\theta$, initially 
+    in the $xz$ plane, is carried out first, then rotation $\phi$ about the $z$ axis. Orientation distributions
+    are described as rotations about two perpendicular axes $\delta_1$ and $\delta_2$
+    in the frame of the cylinder itself, which when $\theta = \phi = 0$ are parallel to the $Y$ and $X$ axes.