How can I fix the 'wrong row length' error when adding a row to a CIF file with the gemmi library in Python?

[lobnaOmar20]

why everytime I try to add a row to my cif file using this:

loop = block.find_loop('_atom_type_symbol').get_loop()
loop.add_row(['Au'], pos=0)
loop.add_row(['Zr'])  # appends
list(block.find_loop('_atom_type.symbol'))
['Au', 'C', 'CL', 'N', 'O', 'P', 'S', 'Zr']

which is exactly the same as the one in the documentation
I get
(RuntimeError: add_row(): wrong row length.)

I tried different positions in here
loop.add_row(['Au'], pos=0)
with no better result, I always get the same error.

I used gemmi for a lot of things for my cif files. It is awesome.

I just want to add sodium atoms to my cif file.

[wojdyr]

In mmCIF files _atom_type category usually has one column with symbol.
In small molecule CIF files it often has multiple columns, such as

loop_
 _atom_type_symbol
 _atom_type_description
 _atom_type_scat_dispersion_real
 _atom_type_scat_dispersion_imag
 _atom_type_scat_source

The list argument to add_row() needs to have as many values as there are columns in the loop.

[lobnaOmar20]

you mean cif.quotelist() ?? I tried with that as well but no better result.

[lobnaOmar20]

loop = block.find_loop_item('_atom_site_label').loop
loop.tags 

['_atom_site_label',
'_atom_site_occupancy',
'_atom_site_fract_x',
'_atom_site_fract_y',
'_atom_site_fract_z',
'_atom_site_adp_type',
'_atom_site_U_iso_or_equiv',
'_atom_site_type_symbol']

should I do this??
loop.add_row(['Na1'],['1.0'],[0.141800],[0.000000],[0.667300],['Uiso'],[0.050000],[sodium])

[lobnaOmar20]

tried this as well, but I always get an error

add_row(): incompatible function arguments. The following argument types are supported:
1. (self: gemmi.cif.Loop, new_values: List[str], pos: int = -1) -> None

[wojdyr]

one list of strings

loop.add_row(['Na1' , '1.0', '0.141800', '0.000000', '0.667300', 'Uiso', '0.050000', 'sodium'])

[lobnaOmar20]

thank you soooo much it finally worked.