Update dft_parser; Add tests for dft_parser

pyscf/dft/dft_parser.py

@@ -29,13 +29,11 @@
 @lru_cache(128)
 def parse_dft(dft_method):
     ''' conventional dft method ->
-    (xc, enable nlc, dispersion, with 3-body dispersion)
+    (xc, enable nlc, (xc for dftd3, dispersion version, with 3-body dispersion))
     '''
     if not isinstance(dft_method, str):
-        return dft_method, None, None, False
+        return dft_method, None, (dft_method, None, False)
     method_lower = dft_method.lower()
-    xc = dft_method
-    disp = None
 
     # special cases:
     # - wb97x-d is not supported yet
@@ -53,24 +51,30 @@ def parse_dft(dft_method):
     if method_lower == 'wb97x-d3bj':
         return 'wb97x-v', False, ('wb97x', 'd3bj', False)
 
-    # J. Chem. Theory Comput. 2013, 9, 1, 263–272
+    # J. Chem. Theory Comput. 2013, 9, 1, 263-272
     if method_lower in ['wb97x-d3']:
         raise NotImplementedError('wb97x-d3 is not supported yet.')
 
     if method_lower.endswith('-3c'):
         raise NotImplementedError('*-3c methods are not supported yet.')
 
+    xc = dft_method
+    disp = None
     for d in DISP_VERSIONS:
         if method_lower.endswith(d):
             disp = d
             xc = method_lower.replace(f'-{d}','')
-            return xc, None, (xc, disp, False)
         if method_lower.endswith(d+'2b'):
             disp = d
             xc = method_lower.replace(f'-{d}2b', '')
-            return xc, None, (xc, disp, False)
         if method_lower.endswith(d+'atm'):
             disp = d
             xc = method_lower.replace(f'-{d}atm', '')
-            return xc, None, (xc, disp, True)
+
+        if disp is not None:
+            if xc in ('b97m', 'wb97m', 'wb97x'):
+                return xc+'-v', False, (xc, disp, False)
+            else:
+                return xc, None, (xc, disp, False)
+
     return xc, None, (xc, None, False)

pyscf/dft/libxc.py

@@ -923,9 +923,9 @@ def is_gga(xc_code):
 @lru_cache(100)
 def is_nlc(xc_code):
     enable_nlc = dft_parser.parse_dft(xc_code)[1]
-    if enable_nlc is False:
+    if not (enable_nlc is None and enable_nlc):
         return False
-
+    # identify nlc by xc_code itself if enable_nlc is None
     if isinstance(xc_code, str):
         if xc_code.isdigit():
             return _itrf.LIBXC_is_nlc(ctypes.c_int(int(xc_code)))
@@ -1092,7 +1092,6 @@ def parse_xc(description):
         (hybrid, alpha, omega), ((libxc-Id, fac), (libxc-Id, fac), ...)
     '''  # noqa: E501
 
-    description = dft_parser.parse_dft(description)[0]
     hyb = [0, 0, 0]  # hybrid, alpha, omega (== SR_HF, LR_HF, omega)
     if description is None:
         return tuple(hyb), ()
@@ -1111,6 +1110,8 @@ def parse_xc(description):
                       'To restore the VWN5 definition, you can put the setting '
                       '"B3LYP_WITH_VWN5 = True" in pyscf_conf.py')
 
+    description = dft_parser.parse_dft(description)[0]
+
     def assign_omega(omega, hyb_or_sr, lr=0):
         if hyb[2] == omega or omega == 0:
             hyb[0] += hyb_or_sr
@@ -1237,6 +1238,8 @@ def possible_c_for(key):
             parse_token(token, 'C')
     else:
         for token in description.replace('-', '+-').replace(';+', ';').split('+'):
+            # dftd3 cannot be used in a custom xc description
+            assert '-d3' not in token
             parse_token(token, 'compound XC', search_xc_alias=True)
     if hyb[2] == 0: # No omega is assigned. LR_HF is 0 for normal Coulomb operator
         hyb[1] = 0

pyscf/dft/test/test_libxc.py

@@ -341,6 +341,20 @@ def test_m06(self):
         self.assertAlmostEqual(abs(numpy.hstack([fxc[i] for i in [0,1,2,4,6,9]])-fxc_ref).max(), 0, 7)
         self.assertAlmostEqual(abs(numpy.hstack([kxc[i] for i in [0,1,2,3,5,7,10,12,15,19]])-kxc_ref).max(), 0, 6)
 
+    def test_dft_parser(self):
+        from pyscf.dft.dft_parser import parse_dft
+        self.assertEqual(parse_dft('wb97m-d3bj'), ('wb97m-v', False, ('wb97m', 'd3bj', False)))
+        self.assertEqual(dft.libxc.parse_xc('wb97m-d3bj')[1][0][0] == 531)
+        self.assertTrue(not dft.libxc.is_nlc('wb97m-d3bj'))
+
+        self.assertEqual(parse_dft('wb97-d3zerom'), ('wb97', None, ('wb97', 'd3zerom', False)))
+        self.assertTrue(not dft.libxc.is_nlc('wb97-d3zerom'))
+
+        self.assertEqual(parse_dft('wb97m-d3bjatm'), ('wb97m-v', False, ('wb97m', 'd3bj', True)))
+        self.assertTrue(not dft.libxc.is_nlc('wb97m-d3bjatm'))
+
+        self.assertEqual(parse_dft('wb97x-d3zero2b'), ('wb97x-v', False, ('wb97x', 'd3zero', False)))
+        self.assertTrue(not dft.libxc.is_nlc('wb97x-d3zero2b'))
 
 if __name__ == "__main__":
     print("Test libxc")

pyscf/dft/xcfun.py

@@ -28,7 +28,7 @@
 import numpy
 from pyscf import lib
 from pyscf.dft.xc.utils import remove_dup, format_xc_code
-from pyscf.dft import xc_deriv
+from pyscf.dft import xc_deriv, dft_parser
 from pyscf import __config__
 
 _itrf = lib.load_library('libxcfun_itrf')
@@ -318,6 +318,9 @@ def is_gga(xc_code):
 VV10_XC.update([(5000+i, VV10_XC[key]) for i, key in enumerate(VV10_XC)])
 
 def is_nlc(xc_code):
+    enable_nlc = dft_parser.parse_dft(xc_code)[1]
+    if not (enable_nlc is None and enable_nlc):
+        return False
     fn_facs = parse_xc(xc_code)[1]
     return any(xid >= 5000 for xid, c in fn_facs)
 
@@ -420,6 +423,8 @@ def parse_xc(description):
     elif not isinstance(description, str): #isinstance(description, (tuple,list)):
         return parse_xc('%s,%s' % tuple(description))
 
+    description = dft_parser.parse_dft(description)[0]
+
     def assign_omega(omega, hyb_or_sr, lr=0):
         if hyb[2] == omega or omega == 0:
             hyb[0] += hyb_or_sr
@@ -430,6 +435,7 @@ def assign_omega(omega, hyb_or_sr, lr=0):
             hyb[2] = omega
         else:
             raise ValueError('Different values of omega found for RSH functionals')
+
     fn_facs = []
     def parse_token(token, suffix, search_xc_alias=False):
         if token:
@@ -503,6 +509,8 @@ def parse_token(token, suffix, search_xc_alias=False):
             parse_token(token, 'C')
     else:
         for token in description.replace('-', '+-').replace(';+', ';').split('+'):
+            # dftd3 cannot be used in a custom xc description
+            assert '-d3' not in token
             parse_token(token, 'XC', search_xc_alias=True)
     if hyb[2] == 0: # No omega is assigned. LR_HF is 0 for normal Coulomb operator
         hyb[1] = 0