Changeset 348557a in sasmodels

Timestamp:

Mar 16, 2016 11:41:50 AM (8 years ago)

Author:

richardh

Branches:

master, core_shell_microgels, costrafo411, magnetic_model, release_v0.94, release_v0.95, ticket-1257-vesicle-product, ticket_1156, ticket_1265_superball, ticket_822_more_unit_tests

Children:

5041682

Parents:

91c5fdc

Message:

rkh new hayter_msa, new squarewell, unit test to lamellar

Location:

sasmodels/models

Files:

• hayter_msa.py (moved) (moved from sasmodels/models/HayterMSAsq.py) (4 diffs)
• hayter_msa_kernel.c (moved) (moved from sasmodels/models/HayterMSAsq_kernel.c) (3 diffs)
• lamellar.py (modified) (1 diff)
• squarewell.py (added)

sasmodels/models/hayter_msa.py

@@ -45 +45 @@
 from numpy import inf
 
-source = ["HayterMSAsq_kernel.c"]
+source = ["hayter_msa_kernel.c"]
 
-name = "HayterMSAsq"
+name = "hayter_msa"
 title = "Hayter-Penfold MSA charged sphere interparticle S(Q) structure factor"
 description = """\
@@ -57 +57 @@
         parameters used in P(Q).
 """
-single = False  # double precision only for now
+single = False  # double precision only!
 
 # pylint: disable=bad-whitespace, line-too-long
@@ -99 +99 @@
             effect_radius_pd_n=40)
 #
-# attempt to use same values as old sasview unit test
+# attempt to use same values as old sasview unit test at Q=.001 was 0.0712928, 
+# then add lots new ones assuming values from new model are OK, need some low Q values to test the small Q Taylor expansion
 tests = [
     [{'scale': 1.0,
@@ -110 +111 @@
       'dielectconst': 78.0,
       'effect_radius_pd': 0},
-     [0.0010], [0.0712928]]
+     [0.00001,0.0010,0.01,0.075], [0.0711646,0.0712928,0.0847006,1.07150]],
+    [{'scale': 1.0,
+      'background': 0.0,
+      'effect_radius': 20.75,
+      'charge': 19.0,
+      'volfraction': 0.0192,
+      'temperature': 298.0,
+      'saltconc': 0.05,
+      'dielectconst': 78.0,
+      'effect_radius_pd': 0.1,
+      'effect_radius_pd_n': 40},
+     [0.00001,0.0010,0.01,0.075], [0.450272,0.450420,0.465116,1.039625]]
     ]
 

sasmodels/models/hayter_msa_kernel.c

@@ -45 +45 @@
         //                      Kappa (Debye-Huckel screening length in m)
         //      and             gamma Exp(-k)
+        
+        // the zz*VolFrac/Vp is for the counterions from the micelle, assumed monovalent, the 2.0*cs if for added salt, assumed 1:1 electolyte 
         IonSt=0.5 * Elcharge*Elcharge*(zz*VolFrac/Vp+2.0*cs);
         Kappa=sqrt(2*Beta*IonSt/Perm);     //Kappa calc from Ionic strength
@@ -505 +507 @@
         ak2 = akz*akz;
         
-        if (qq<=0.0) {
+        qk = qq/gMSAWave[13];
+        q2k = qk*qk;
+        if (qk<=1.0e-08) {
                 SofQ = -1.0/gMSAWave[0];
         } else {
-                qk = qq/gMSAWave[13];
-                q2k = qk*qk;
+        // this rescales Q.sigma = 2.Q.Radius, so is hard to predict the value to test the function
+        if (qk<=0.01) {
+                // try Taylor series expansion at small qk (RKH Feb 2016, with help from Mathematica), 
+                // transition point may need to depend on precision of cpu used and ALAS on the values of some of the parameters !
+                // note have adsorbed a factor 24 from SofQ=
+                // needs thorough test over wide range of parameter space!
+                // there seem to be some rounding issues here in single precision, must use double
+                aqk = gMSAWave[0]*(8.0+2.0*etaz) + 6*gMSAWave[1] -12.0*gMSAWave[3] 
+                        -24*(gekz*(1.0+akz) -ck*akz*gMSAWave[2] +gMSAWave[3]*(ck-1.0) +(gMSAWave[2]-gMSAWave[3]*akz)*sk )/ak2
+                        +q2k*( -(gMSAWave[0]*(48.0+15.0*etaz) +40.0*gMSAWave[1])/60.0 +gMSAWave[3] 
+                        +(4.0/ak2)*(gekz*(9.0+7.0*akz) +ck*(9.0*gMSAWave[3] -7.0*gMSAWave[2]*akz) +sk*(9.0*gMSAWave[2] -7.0*gMSAWave[3]*akz)) );
+                SofQ = 1.0/(1.0-gMSAWave[10]*aqk);
+        } else {
                 qk2 = 1.0/q2k;
                 qk3 = qk2/qk;
                 qqk = 1.0/(qk*(q2k+ak2));
-                sink = sin(qk);
-                cosk = cos(qk);
+                SINCOS(qk,sink,cosk);
                 asink = akz*sink;
                 qcosk = qk*cosk;
@@ -525 +539 @@
                 aqk=aqk +gMSAWave[3]*(cosk-1.0)*qk2;
                 aqk=aqk -gekz*(asink+qcosk)*qqk;
-                SofQ = 1.0/(1.0-e24*aqk);
-        }
+                SofQ = 1.0/(1.0  -e24*aqk);
+        } }
         return (SofQ);
 }

sasmodels/models/lamellar.py

@@ -99 +99 @@
 oldname = 'LamellarModel'
 oldpars = dict(sld='sld_bi', solvent_sld='sld_sol', thickness='bi_thick')
-
+tests = [
+        [ {'scale': 1.0, 'background' : 0.0, 'thickness' : 50.0, 'sld' : 1.0,'solvent_sld' : 6.3, 'thickness_pd' : 0.0, 
+           }, [0.001], [882289.54309]]
+        ]
+# ADDED by: converted by PAK? (or RKH?)     ON: 16Mar2016 - RKH adding unit tests from sasview to early 2015 conversion
+#  [(qx1, qy1), (qx2, qy2), ...], [I(qx1,qy1), I(qx2,qy2), ...]],