'''
Created on 24.05.2013
'''
import itertools as itools
[docs]def cartesian_product(parameter_dict, combined_parameters = ()):
''' Generates a Cartesian product of the input parameter dictionary.
For example:
>>> print cartesian_product({'param1':[1,2,3], 'param2':[42.0, 52.5]})
{'param1':[1,1,2,2,3,3],'param2': [42.0,52.5,42.0,52.5,42.0,52.5]}
:param param_dict:
Dictionary containing parameter names as keys and iterables of data to explore.
:param combined_parameter_list:
Tuple of tuples. Defines the order of the parameters and parameters that are
linked together.
If an inner tuple contains only a single item, you can spare the
inner tuple brackets.
For example:
>>> print cartesian_product( {'param1': [42.0, 52.5], 'param2':['a', 'b'],\
'param3' : [1,2,3]}, ('param3',('param1', 'param2')))
{param3':[1,1,2,2,3,3],'param1' : [42.0,52.5,42.0,52.5,42.0,52.5],\
'param2':['a','b','a','b','a','b']}
:returns: Dictionary with cartesian product lists.
'''
if not combined_parameters:
combined_parameters = list(parameter_dict)
else:
combined_parameters = list(combined_parameters)
for idx,item in enumerate(combined_parameters):
if isinstance(item,basestring):
combined_parameters[idx]= (item,)
iterator_list = []
for item_tuple in combined_parameters:
inner_iterator_list = [parameter_dict[key] for key in item_tuple]
zipped_iterator = itools.izip(*inner_iterator_list)
iterator_list.append(zipped_iterator)
result_dict ={}
for key in parameter_dict:
result_dict[key]=[]
cartesian_iterator = itools.product(*iterator_list)
for cartesian_tuple in cartesian_iterator:
for idx, item_tuple in enumerate(combined_parameters):
for inneridx,key in enumerate(item_tuple):
result_dict[key].append(cartesian_tuple[idx][inneridx])
return result_dict