Changes in sasmodels/models/core_shell_cylinder.py [e31b19a:2d81cfe] in sasmodels

File:

• sasmodels/models/core_shell_cylinder.py (modified) (3 diffs)

sasmodels/models/core_shell_cylinder.py

@@ -5 +5 @@
 The output of the 2D scattering intensity function for oriented core-shell
 cylinders is given by (Kline, 2006 [#kline]_). The form factor is normalized
-by the particle volume. Note that in this model the shell envelops the entire
-core so that besides a "sleeve" around the core, the shell also provides two
-flat end caps of thickness = shell thickness. In other words the length of the
-total cyclinder is the length of the core cylinder plus twice the thickness of
-the shell. If no end caps are desired one should use the
-:ref:`core-shell-bicelle` and set the thickness of the end caps (in this case
-the "thick_face") to zero.
+by the particle volume.
 
 .. math::
@@ -39 +33 @@
 
 and $\alpha$ is the angle between the axis of the cylinder and $\vec q$,
-$V_s$ is the total volume (i.e. including both the core and the outer shell),
-$V_c$ is the volume of the core, $L$ is the length of the core,
+$V_s$ is the volume of the outer shell (i.e. the total volume, including
+the shell), $V_c$ is the volume of the core, $L$ is the length of the core,
 $R$ is the radius of the core, $T$ is the thickness of the shell, $\rho_c$
 is the scattering length density of the core, $\rho_s$ is the scattering
@@ -141 +135 @@
     return 0.5 * (ddd) ** (1. / 3.)
 
+def VR(radius, thickness, length):
+    """
+    Returns volume ratio
+    """
+    whole = pi * (radius + thickness) ** 2 * (length + 2 * thickness)
+    core = pi * radius ** 2 * length
+    return whole, whole - core
+
 def random():
     outer_radius = 10**np.random.uniform(1, 4.7)