set_spacegroup_from_dbase(mystr, mode, **kwargs)

Creates a Shubnikov (spg_type) or superspace (superspacegroup_type) group from the database. Therefore, the database must be installed in the computer. If CrysFML08 is in your computer, define the environment variable CRYSFML_DB and set it to the directory Src/Databases in CrysFML08. If you have installed the FullProf suite, check that the environment variable FULLPROF has been set. With either of the two environment variables, PyCrysFML will locate the database. Another option is to pass as an argument the path to the database (see below).

Parameters:

• mystr (str) –

  string specifying the Shubnikov or superspace group.

  • From number.

    • Shubnikov group: mystr = "1236"

    • Superspace group: mystr = "13232"

  • From the standard symbol.

    • Shubnikov group: mystr = "Pn'ma"`

    • Superspace group: mystr = "Pnma(0,0,g)0s0"

  • From the Hall symbol.

    • space #41 of standard symbol Aba2: mystr = "B 2 C B"

  • From the unified symbol.

    • Shubnikov group: mystr = "UNI Pnna.1'_a[Pncm]"

• mode – type of group: ‘shubn’ | ‘super’.

• kwargs – optional arguments.

• kwargs['xyztype'] (str) – coordinates notation: ‘xyz’ (default) | ‘abc’ | ‘x1x2x3’.

• kwargs['setting'] (str) – setting transformation.

• kwargs['keepdb'] (bool) – if not given, deallocate the database after the group generation.

• kwargs['parent'] (str) – if given, set the parent group symbol.

• kwargs['database_path'] (str) – database path. Required if environment variables CRYSFML_DB and FULLPROF are not set.

• kwargs['trn_to'] (bool) – if given, transformation matrices between standard and new setting (if given) are computed.

Returns:

space group

Return type:

dict (spg_type or superspacegroup_type)

>>> from pycrysfml import cfml_gspacegroups
>>> sg = cfml_gspacegroups.set_spacegroup_from_dbase("Pn'ma","shubn",setting="-c,b,a;0,0,0")
>>> for k in sg:
...   print(f'{k :>16}: {sg[k]}')
...
          multip: 8
               d: 4
             inv: [0 0 0 0 0 0 0 0]
              op: [{'time_inv': 1, 'dt': 1, 'mat': array([[1., 0., 0., 0.],
                  [0., 1., 0., 0.],
                  [0., 0., 1., 0.],
                  [0., 0., 0., 1.]], dtype=float32)}, {'time_inv': 1, 'dt': 1, 'mat': array([[-1. ,  0. ,  0. ,  0.5],
                  [ 0. , -1. ,  0. ,  0.5],
                  [ 0. ,  0. ,  1. ,  0.5],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}, {'time_inv': -1, 'dt': 1, 'mat': array([[-1. ,  0. ,  0. ,  0. ],
                  [ 0. ,  1. ,  0. ,  0.5],
                  [ 0. ,  0. , -1. ,  0. ],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}, {'time_inv': -1, 'dt': 1, 'mat': array([[ 1. ,  0. ,  0. ,  0.5],
                  [ 0. , -1. ,  0. ,  0. ],
                  [ 0. ,  0. , -1. ,  0.5],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}, {'time_inv': -1, 'dt': -1, 'mat': array([[-1.,  0.,  0.,  0.],
                  [ 0., -1.,  0.,  0.],
                  [ 0.,  0., -1.,  0.],
                  [ 0.,  0.,  0.,  1.]], dtype=float32)}, {'time_inv': -1, 'dt': -1, 'mat': array([[ 1. ,  0. ,  0. ,  0.5],
                  [ 0. ,  1. ,  0. ,  0.5],
                  [ 0. ,  0. , -1. ,  0.5],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}, {'time_inv': 1, 'dt': -1, 'mat': array([[ 1. ,  0. ,  0. ,  0. ],
                  [ 0. , -1. ,  0. ,  0.5],
                  [ 0. ,  0. ,  1. ,  0. ],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}, {'time_inv': 1, 'dt': -1, 'mat': array([[-1. ,  0. ,  0. ,  0.5],
                  [ 0. ,  1. ,  0. ,  0. ],
                  [ 0. ,  0. ,  1. ,  0.5],
                  [ 0. ,  0. ,  0. ,  1. ]], dtype=float32)}]
         symb_op: ['x,y,z,+1','-x+1/2,-y+1/2,z+1/2,+1','-x,y+1/2,-z,-1', 'x+1/2,-y,-z+1/2,-1','-x,-y,-z,-1', 'x+1/2,y+1/2,-z+1/2,-1', 'x,-y+1/2,z,+1', '-x+1/2,y,z+1/2,+1']
        magnetic: True
standard_setting: False
          numspg: 0
          numshu: 541
          numops: 8
         centred: 1
     anticentred: 2
        mag_type: 3
         num_lat: 0
        num_alat: 0
      parent_num: 62
     bravais_num: 0
         spg_lat: P
         shu_lat: ['P', 'P']
      init_label: Pn'ma
      parent_spg: Pnma
    tfrom_parent:
          centre: Non-centrosymmetric, Anti-centric with -1' @ origin
        spg_symb:
         bns_num: 62.443
          og_num: 62.3.504
        bns_symb: Pn'ma
         og_symb: Pn'ma
            hall: P 2ac' 2n -1'
             uni: Pn'ma
         uni_num:  504
      crystalsys: Orthorhombic
              pg:
          mag_pg: m'mm
            laue:
         setting: -c,b,a;0,0,0
         mat2std: c,b,-a;0,0,0
     mat2std_shu:
         matfrom: -c,b,a;0,0,0
 generators_list: -x+1/2,-y+1/2,z+1/2,+1;-x,y+1/2,-z,-1;x+1/2,-y,-z+1/2,-1;-x,-y,-z,-1;x+1/2,y+1/2,-z+1/2,-1;x,-y+1/2,z,+1;-x+1/2,y,z+1/2,+1
    centre_coord: [0. 0. 0.]
anticentre_coord: [0. 0. 0.]
          lat_tr: []
         alat_tr: []