feat: increase fast cal to muD=7

news/fastcalto7.rst

@@ -0,0 +1,23 @@
+**Added:**
+
+* Fast calculation support up to muD = 7
+
+**Changed:**
+
+* Clarified error message for fast calculation to explicitly states the invalid muD value
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>

src/diffpy/labpdfproc/data/coefficient_list.csv

@@ -1,5 +1,7 @@
--6.543824057313183,2.517676049711881e-10,-430.98705781061807,-1390.1242894055792,-2233.6043531698424,-2624.226082870084,-2590.22123249732
-5.020666247920394,-4.676545705328227e-10,875.3743680589598,2744.521375373735,4366.230491983095,5113.620084734874,5051.51673764446
-1.8615172482459748,3.25649449911046e-10,-663.8228448830648,-2027.2101338882571,-3194.0427904869357,-3728.3876362721985,-3684.6430045258744
--1.9688714316525813,0.9999999998992586,224.64320300800793,666.0546805817288,1038.3830530062712,1207.4338980088214,1193.1790131535502
-0.9819818977427489,1.1680695590205036e-11,-28.533774174029173,-82.17596308875525,-126.6770208129477,-146.65755463691826,-144.8506009433783
+-20619.128648244743,2.4364997877410417e-06,26505.585137008606,-337279.3213902739,-1056051.2792994028,-1815539.1160187968,-2372171.980894541,-2642993.4538858426
+56203.20048346139,-6.774323967911372e-06,-51225.01460831775,1005023.6254387972,3051609.2101441943,5201294.212075991,6773264.754466731,7538833.212217793
+-63802.106117440504,7.845612740225726e-06,33089.880661840034,-1242527.9972772636,-3668761.3028854067,-6202335.40819644,-8050708.344579743,-8951452.327576341
+38603.18842240787,-4.844608638276231e-06,-4028.752491140328,816333.2796219026,2349291.871863084,3940828.5623758254,5099123.959731602,5663734.051678175
+-13126.533425725584,1.6822282153058894e-06,-4395.4012467221355,-300757.7094990732,-845218.597424347,-1407243.8630987857,-1815244.4369415767,-2014105.8565458413
+2378.155272695758,0.9999996885549859,1912.0755691304305,58944.34388638723,162014.93660541167,267802.2088119374,344395.5526651557,381710.2334140182
+-178.70587585316136,2.4018054840276848e-08,-234.76082555771987,-4803.1698085743365,-12928.521798999534,-21220.235622246797,-27207.092578054173,-30121.285267280207

src/diffpy/labpdfproc/functions.py

@@ -16,7 +16,7 @@
 CVE_METHODS = ["brute_force", "polynomial_interpolation"]
 
 # Pre-computed datasets for polynomial interpolation (fast calculation)
-MUD_LIST = [0.5, 1, 2, 3, 4, 5, 6]
+MUD_LIST = [0.5, 1, 2, 3, 4, 5, 6, 7]
 CWD = Path(__file__).parent.resolve()
 MULS = np.loadtxt(CWD / "data" / "inverse_cve.xy")
 COEFFICIENT_LIST = np.array(
@@ -206,25 +206,28 @@ def _cve_brute_force(input_pattern, mud):
 
 def _cve_polynomial_interpolation(input_pattern, mud):
     """Compute cve using polynomial interpolation method,
-    raise an error if the mu*D value is out of the range (0.5 to 6).
+    raise an error if the mu*D value is out of the range (0.5 to 7).
     """
-    if mud > 6 or mud < 0.5:
+    if mud > 7 or mud < 0.5:
         raise ValueError(
-            f"mu*D is out of the acceptable range (0.5 to 6) "
+            f"Input mu*D = {mud} is out of the acceptable range "
+            f"({min(MUD_LIST)} to {max(MUD_LIST)}) "
             f"for polynomial interpolation. "
             f"Please rerun with a value within this range "
             f"or specifying another method from {*CVE_METHODS, }."
         )
-    coeff_a, coeff_b, coeff_c, coeff_d, coeff_e = [
+    coef1, coef2, coef3, coef4, coef5, coef6, coef7 = [
         interpolation_function(mud)
         for interpolation_function in INTERPOLATION_FUNCTIONS
     ]
     muls = np.array(
-        coeff_a * MULS**4
-        + coeff_b * MULS**3
-        + coeff_c * MULS**2
-        + coeff_d * MULS
-        + coeff_e
+        coef1 * MULS**6
+        + coef2 * MULS**5
+        + coef3 * MULS**4
+        + coef4 * MULS**3
+        + coef5 * MULS**2
+        + coef6 * MULS
+        + coef7
     )
     cve = 1 / muls
 

tests/test_functions.py

@@ -160,8 +160,8 @@ def test_compute_cve(input_xtype, expected, mocker):
     "inputs, msg",
     [
         (
-            {"mud": 7, "method": "polynomial_interpolation"},
-            f"mu*D is out of the acceptable range (0.5 to 6) "
+            {"mud": 10, "method": "polynomial_interpolation"},
+            f"mu*D = 10 is out of the acceptable range (0.5 to 7) "
             f"for polynomial interpolation. "
             f"Please rerun with a value within this range "
             f"or specifying another method from {*CVE_METHODS, }.",