Use cases¶
from mmcif.mmcif import CifFile, CifWrapper, CifFileWriter
import mmcif.mmcif_io as mmcif
Creating objects¶
Example 1 - Creating an mmCIF like dictionary by hand (manually)¶
mmcif_like = {
'TEST_CIF': {
'_test_category_1': {
'test_value_1': 1,
'test_value_2': 2,
'test_value_3': 3
},
'_test_category_2': {# Loop/table
'test_value_1': [1, 2, 3, 4],
'test_value_2': ["Sleepy", "Dopey", "Bashful", "Grumpy"],
'test_value_3': [\
'A ->\nLINE = A',
'B ->\nLINE = B',
'C ->\nLINE = C',
'D ->\nLINE = D'
]
}
}
}
Example 2 - Creating a CifWrapper object from mmCif-like dictionaries¶
cif_wrapper = CIFWrapper(mmcif_like)
print(cif_wrapper.data_id, cif_wrapper)
Example 3 - Creating an mmCif-like dictionary from a CifWrapper object¶
data_dict = cif_wrapper.unwrap()
print(data_dict)
Example 4 - Creating a CifFile object from an mmCif-like dictionary¶
Method 1: (instantiation)¶
cif_file_1 = CifFile(filename="usage-test-1.cif", mmcif_data_map=mmcif_like)
Method 2: (dictionary import)¶
cif_file_2 = CifFile(filename="usage-test-2.cif")
cif_file_2.import_mmcif_data_map(mmcif_like)
print(cif_file_1, cif_file_2)
Reading from files¶
Example 5 - INPUT: mmCif data files, OUTPUT: mmCif-like dictionary¶
cfr = CifFileReader(input='data')
(cif_id, cif_dictionary) = cfr.read(path + "/usage-example.cif", output='cif_dictionary', ignore=["_atom_site", "_atom_site_anisotrop"])
print("mmCIF-like dictionary:", cif_dictionary)
Example 6 - INPUT: mmCif data files, OUTPUT: CIFWrapper object¶
cfr = CifFileReader(input='data')
cif_wrapper = cfr.read(path + "/usage-example.cif", output='cif_wrapper')
print("CIFWrapper:", cif_wrapper)
Example 7 - INPUT: mmCif data files, OUTPUT: CifFile object¶
cfr = CifFileReader(input='data')
cif_file = cfr.read(path + "/usage-example.cif", output='cif_file')
print("CifFile:", cif_file)
Writing to files¶
Using the objects from examples 5, 6, and 7 above
Example 8 - INPUT: mmCif-like dictionary¶
cfd1 = CifFileWriter("./cif_dictionary_test-1.cif")
Method 1¶
NO datablocks defined in mmCIF-like dictionary (Define your own) Datablock ID defaults to filename defined in CifFileWriter if none provided.
cfd1.write(cif_dictionary)
Method 2: DataBlocks defined in mmCIF-like dictionary¶
cfd2 = CifFileWriter("./cif_dictionary_test-2.cif")
cfd2.write({cif_id:cif_dictionary})
Example 9 - INPUT: CIFWrapper object¶
cfw = CifFileWriter("./cif_wrapper_test.cif")
cfw.write(cif_wrapper)
Example 10 - INPUT: CifFile object¶
cff = CifFileWriter("./cif_file_test.cif")
cff.write(cif_file)
Using an mmCIF-like python dictionary¶
Using the CIF dictionary directly to access data. The following examples use the objects from examples 5, 6, and 7 above.
Data are accessed using standard data access mechanisms for python dictionaries:
user_dict['_cif_category']['cif_item']
Example 11 - Accessing the value of an item¶
print("_test_keyword.field_1", cif_dictionary["_test_keyword"]["field_1"])
Example 12 - Accessing all items of a category¶
print("_valid_CIF", cif_dictionary["_valid_CIF"])
Using a CIFWrapper object¶
The CIFWrapper object is a wrapper for the mmCIF-like dictionary used to emulate python objects. Data are accessed using familiar ‘dot’ notation:
user_dict._cif_category.cif_item
Categories (tables) also have useful methods for filtering i.e.: search() and searchiter()
cif_wrapper_2 = cfr.read(path + "/1smv.cif", output='cif_wrapper')
# Example 13 - Check table exists and get all the contents of the table
if '_struct_ref_seq_dif' in cif_wrapper_2:
print(cif_wrapper_2._struct_ref_seq_dif)
# Example 14 - Check column exists in a table and get all contents of the column
if 'details' in cif_wrapper_2._struct_ref_seq_dif and cif_wrapper_2._struct_ref_seq_dif.details:
print(cif_wrapper_2._struct_ref_seq_dif.details)
# Example 15 - Search a table for rows where values in column match and get
# all results as dict in the form {match_row_index : {row}}
print(cif_wrapper_2._struct_ref_seq_dif.search('details', 'DELETION'))
# Example 16 - Iterate over search results (table rows) where values in
# column match the given searchterm and get rows as
# {column_name: value_for_row}
for searchResult in cif_wrapper_2._struct_ref_seq_dif.searchiter('details', 'DELETION'):
print(searchResult)
break # only show one to demonstrate the principle
# Example 17 - Iterate over all rows in a table and get rows as
# {column_name: value_for_row}
for row in cif_wrapper_2._struct_ref_seq_dif:
print(row)
break # only show one to demonstrate the principle
Using a CifFile object¶
Using the CifFile object to access, edit and update mmCIF data. The following examples use the CifFile object objects from example 7 above.
Data are manipulated using the accessors and mutators provided:
NB: See the Test suite in mmCif.test for more examples
Example 18 - Working with CifFile¶
print("DataBlock ids:", cif_file.getDataBlockIds()) #List all datablock ids
print("DataBlock objects:", cif_file.getDataBlocks()) #List all datablock objects
data_block_1 = cif_file.getDataBlock("TEST_CIF") #Get a specific datablock
data_block_1 = cif_file.getDataBlocks()[0] #Get the first datablock
data_block_2 = cif_file.setDataBlock("BLOCK_2") # Create another empty datablock
data_block_3 = cif_file.setDataBlock("BLOCK_3") # Create another empty datablock
cif_file.removeChild(data_block_2) # Remove datablock (Method 1 - given object)
cif_file.removeChild("BLOCK_3") # Remove datablock (Method 2 - given ID)
print("RECYCLED DATABLOCKS:", cif_file.recycleBin) # Removed objects are stored in a recycle bin
Example 19 - Working with DataBlock¶
"""NB: Category and SaveFrame are handled in the same manner"""
data_block_1 = cif_file.getDataBlock("TEST_CIF") #Get a specific datablock
data_block_4 = cif_file.setDataBlock("BLOCK_4") # Create another empty datablock
data_block_5 = cif_file.setDataBlock("BLOCK_5") # Create another empty datablock
data_block_5.getId()) # Get the datablock ID
data_block_5.updateId("BLOCK_5.1") # Change the datablock ID
print("Category ids:", data_block_1.getCategoryIds()) #List all category ids
print("Category objects:", data_block_1.getCategories()) #List all category objects
category_1 = data_block_1.getCategory("_test_keyword") #Get a specific category
category_2 = data_block_4.setCategory("CATEGORY_2") #Create an empty category
category_3 = data_block_4.setCategory("CATEGORY_3") #Create an empty category
data_block_4.removeChild(category_2) # Remove category (Method 1 - given object)
data_block_4.removeChild("CATEGORY_3") # Remove category (Method 2 - given ID)
data_block_5.remove()) # Remove datablock from CifFile
print("RECYCLED CATEGORIES:", data_block_4.recycleBin) # Removed objects are stored in a recycle bin
Example 20 - Working with Category¶
category_1 = data_block_1.getCategory("_test_keyword") #Get a specific category
category_4 = data_block_4.setCategory("CATEGORY_4") # Create another empty category
category_5 = data_block_4.setCategory("CATEGORY_5") # Create another empty category
print("Item names:", category_1.getItemNames()) #List all item names
print("Item objects:", category_1.getItems()) #List all item objects
item_1 = category_1.getItem("field_1") #Get a specific item
item_2 = category_4.setItem("ITEM_2") #Create an empty item
item_3 = category_4.setItem("ITEM_3") #Create an empty item
category_4.removeChild(item_2) # Remove item (Method 1 - given object)
category_4.removeChild("ITEM_3") # Remove item (Method 2 - given ID)
category_5.remove()) # Remove category from DataBlock
print("RECYCLED ITEMS:", category_4.recycleBin) # Removed objects end up in the recycle bin
Example 21 - Working with Item¶
item_1 = category_1.getItem("field_1") #Get a specific item
item_4 = category_4.setItem("ITEM_4") # Create another empty item
item_5 = category_4.setItem("ITEM_5") # Create another empty item
print("Value (raw):", item_1.getRawValue()) #Get raw item value (Method 1 - using accessor)
print("Value (raw):", item_1.value #Get raw item value (Method 2 - using attribute)
print("Value (formated):", item_1.getFormattedValue()) #Get the formated value (for file export)
item_4.setValue("VALUE_2") #Set the item value
item_5.setValue([9, 8, 7, 6, 5]) #Set the item value
item_5.remove()) # Remove item from Category
print("RECYCLED ITEMS:", category_4.recycleBin) # Removed objects end up in the recycle bin
Example 22 - Method chaining¶
For every object the setXXXX() method always returns the this you are
trying to set. If no object is present it creates a new one and returns it.
setXXXX() can therefor be used as both accessor and mutator
cif_file.setDataBlock("BLOCK_6").setCategory("CATEGORY_6").setItem("ITEM_6").setValue("VALUE_6")