Converting from gemmi.cif.Block to gemmi.ReflnBLock

[LuisA92]

Hello,

I was wondering if there is a way to convert a gemmi.cif.Block to a gemmi.ReflnBlock.

I would like to do the following:

doc = gemmi.cif.read('/.cif')
rblock = gemmi_cif.sole_block()
mtz = gemmi.CifToMtz().convert_block_to_mtz(rblock)

[wojdyr]

There is such a function, assuming that you mean mmCIF files, but it takes cif.Document. The second line in your example would be:

rblock = gemmi.as_refln_blocks(doc)[0]

The reason why it takes Document not Block is that sometimes, if multiple blocks are present, the subsequent blocks in the file might be missing the space group and cell parameters. In such cases, the function copies them from the first block in the Document. (This approach might be questionable, actually.)

For small molecule files, we have function hkl_cif_as_refln_block that takes cif.Block.