Changeset b9958b3 in sasview for sansmodels/src/sans/models

Timestamp:

Sep 16, 2011 5:03:42 PM (13 years ago)

Author:

Jae Cho <jhjcho@…>

Branches:

master, ESS_GUI, ESS_GUI_Docs, ESS_GUI_batch_fitting, ESS_GUI_bumps_abstraction, ESS_GUI_iss1116, ESS_GUI_iss879, ESS_GUI_iss959, ESS_GUI_opencl, ESS_GUI_ordering, ESS_GUI_sync_sascalc, costrafo411, magnetic_scatt, release-4.1.1, release-4.1.2, release-4.2.2, release_4.0.1, ticket-1009, ticket-1094-headless, ticket-1242-2d-resolution, ticket-1243, ticket-1249, ticket885, unittest-saveload

Children:

ad019b83

Parents:

a5e14410

Message:

additional doc for shulz

File:

• sansmodels/src/sans/models/media/pd_help.html (modified) (2 diffs)

sansmodels/src/sans/models/media/pd_help.html

@@ -58 +58 @@
 the average particle volume such that P(q) = scale*<F*F>/Vol + bkg, where
 F is the scattering amplitude and the < > denote an average over the size
-distribution.  Users should use PD for a size distribution and Sigma for an
-angular distribution.</span></p>
+distribution.  Users should use PD (polydispersity: this definition is different from the typical definition in polymer science) 
+for a size distribution and Sigma for an
+angular distribution (see below).</span></p>
 <p> Note that this computation is very time intensive thus applying polydispersion/angular distrubtion for 
-more than one paramters or increasing Npts values might need extensive patience to complete the computation.</p>
+more than one paramters or increasing Npts values might need extensive patience to complete the computation. Also
+note that even though it is time consuming, it is safer to have larger values of Npts and Nsigmas.</p>
 
 <p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt'><span
@@ -333 +335 @@
 width=80 height=24 src="pd_image012.png"></span><span
 style='font-family:"Times New Roman","serif"'>.</span></p>
-
+<p/>
+<p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt'><span
+style='font-family:"Times New Roman","serif"'>Note that the higher PD (polydispersity)
+ might need higher values of Npts and Nsigmas. For example, at PD = 0.7 and  radisus = 60 A, 
+ Npts >= 160, and Nsigmas >= 15 at least.</span></p>
+ <p/>
 <p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt'><span
 style='font-family:"Times New Roman","serif"'><img width=438 height=232